Cooperation CP 608554 SWIP FP7-ENERGY-2013-1 (Energy) PROJECT PERIODIC REPORT Grant agreement no.: 608554 Project acronym: SWIP Project title: New innovative solutions, components and tools for the integration of wind energy in urban and peri-urban areas Funding Scheme: Collaborative projects (CP) Date of latest version of Annex I against which the assessment will be made: Periodic report: 1 st Periodic Report Period covered: from M01 to M18 (01. October 2013 . 31. March 2015) Project co-ordinator name: Leonardo Subias Subias Project co-ordinator organisation: FUNDACION CIRCE CENTRO DE INVESTIGACION DE RECURSOS Y CONSUMOS ENERGETICOS Phone: + 34 976 76 29 53 Fax: + 34 976 73 20 78 E.mail: [email protected]Project website address: www.swipproject.eu Date of preparation: 31.05.2015 Version: Final version Draft date: 22.12.2014 10:33 Page 1 of 94
1. Publishable Summary ......................................................................................................................... 9 2. Core of the report the period: Project objectives, work progress and achievements, project management .................................................................................................................................................. 13 2.1. Project objectives for the period ................................................................................................... 13
2.2. Work Progress and Achievements during the Period ................................................................... 15
2.2.1. WP1. European framework assessment .................................................................................. 15
2.2.1.1. Task 1.1. Benchmarking of small and mediums size wind turbines technologies ........... 15
2.2.1.2. Task 1.2 Legal and funding status of the sector .............................................................. 17
2.2.1.3. Task 1.3 Energy plans for cities assessment .................................................................... 18
2.2.1.4. Task 1.4 Particular legal requirements for each demo-site ............................................. 19
2.2.1.5. Task 1.5 Social awareness and persuasion ...................................................................... 19
2.2.1.6. Task 1.6 Scalability of the solutions ................................................................................. 21
2.2.2. WP2. Wind resource assessment and urban models .............................................................. 22
2.2.2.1. Task 2.1 Wind resource assessment in the demo-locations ........................................... 22
2.2.2.2. Task 2.2 Wind behaviour simulation in urban and peri-urban areas .............................. 24
2.2.2.4. Deviations from Annex I and corrective actions:............................................................. 27
2.2.3. WP3. Development of innovative solutions for electrical generators .................................... 28
2.2.3.1. Task 3.1 New modular PM generator design .................................................................. 28
2.2.3.2. Task 3.2 Technique for post-assembled magnetization of PM generators ..................... 29
2.2.3.3. Task 3.3 Magnetic gearbox .............................................................................................. 31
2.2.3.4. Task 3.4 Development of a high coercivity materials with zero or drastically-reduced heavy-RE content ................................................................................................................................. 33
2.2.5.1. Task 5.1 Definition of parameters, alarms, communication, operation, and maintenance of the SCADA ....................................................................................................................................... 48
2.2.5.2. Task 5.2 SCADA development and integration ................................................................ 50
2.2.5.3. Task 5.3 Design of the converters and controls for the wind generators ....................... 51
2.2.5.4. Deviations from Annex I and corrective actions .............................................................. 53
2.2.6. WP6. Structure integration in buildings/districts .................................................................... 54
2.2.6.1. Task 6.1 Architecture and structural analysis of the typical urban constructions in Europe and the pilots .......................................................................................................................... 54
2.2.6.2. Task 6.2 Mast’s anchorages for typical urban construction and the three pilots ........... 55
2.2.6.3. Task 6.3 Structure of the masts at Pilot Buildings ........................................................... 55
2.2.7. WP7. Noise, vibration and safety ............................................................................................ 57
2.2.7.1. Task 7.1 Noise and vibration sources assessment ........................................................... 57
2.2.7.2. Task 7.2 Methodology for acoustic modelling and mitigation techniques ..................... 58
2.2.7.3. Task 7.3 Noise and vibration solutions implementation ................................................. 60
2.2.7.4. Task 7.4 Study of safety standards .................................................................................. 62
3.8. SAL ................................................................................................................................................. 87
3.14. TOTAL ............................................................................................................................................ 93
4. ANNEX I. Blade designs reports ........................................................................................................ 94
Figure 1 Information sheet of the city of Rotterdam ...................................................................................... 10 Figure 2 Methodology to design PM generators ............................................................................................. 11 Figure 3 Distribution of the urban wind potential in Netherlands .................................................................. 17 Figure 4 Installation of a WT .Procedure to ask for permissions..................................................................... 19 Figure 5 SWIP project questionnaire ............................................................................................................... 20 Figure 6 Meteo station in Choczewo ............................................................................................................... 23 Figure 7 Meteo station in Kokoszki ................................................................................................................. 23 Figure 8 Meteo station in Zaragoza ................................................................................................................. 24 Figure 9 Choczewo 3D model………………………………………………………………… ..................................................... 23 Figure 10 Kokoszki 3D model…………………………………………………………….…........................................................ 23 Figure 11 Zaragoza 3Dmodel………………………………………..…………………………. ................................................... 24 Figure 12 RANS results. Choczewo Figure 13 RANS results. Zaragoza ........................................................... 25 Figure 14 Choczewo first LES results ........................................................................................................... 24 Figure 15 Zaragoza meshing……………….. ......................................................................................................... 25 Figure 16 Cabauw area ................................................................................................................................ 25 Figure 17Cabauw met mast Figure 18Rödeserberg area ............................................................................... 26 Figure 19 Stratified atmosphere scheme ........................................................................................................ 26 Figure 20 Stratified atmosphere models ......................................................................................................... 27 Figure 21 Design procedure and studies performed to validate the selected designs ................................... 29 Figure 22. Assembly of modern segmented stator with concentrated winding. ............................................ 30 Figure 23. Assembly of modern concentrated winding motor. ...................................................................... 30 Figure 24. Proposed teeth . back iron solution. .............................................................................................. 31 Figure 25 (a) Magnetic planetary gear. (b) Magnetic spur gearing ................................................................. 32 Figure 26. Modulated Magnetic Gear design. ................................................................................................. 32 Figure 27. Initial proposed MG design. ........................................................................................................... 32 Figure 28 Hot-compacted and die-upset Nd-Fe-B magnets process scheme ................................................. 34 Figure 29 Sintered Nd-Fe-B magnets with 3at. % Dy………………………………………………… ................................. 34 Figure 30 Nd-Fe-B magnets properties………………………. .................................................................................. 35 Figure 31 Large volume cell for high pressure high temperature synthesis ................................................... 35 Figure 32 Microscopic images of precursor and sample after HPHT synthesis .............................................. 36 Figure 33 New SPEX 8000 high energy mill ..................................................................................................... 36 Figure 34 Variation of the lift coefficient (Cl) as a function of K/c for K: Critical value and c: chord length ... 39 Figure 35 2D mesh with rotating core (green area) for the V2 wind turbine ................................................. 39 Figure 36 Hybrid mesh for the H30 and H20 wind turbines ............................................................................ 39 Figure 37 Relative velocity magnitude vector (left) and static pressure contours (right) around the aerofoil for the H30 wind turbine ................................................................................................................................. 40 Figure 38 Relative velocity magnitude vector (left) and static pressure contours (right) around the aerofoil for the H20 wind turbine ................................................................................................................................. 40 Figure 39 Examples of architectural integration at Choczewo pilot site ......................................................... 40 Figure 40 Pitch system sketch ......................................................................................................................... 41 Figure 41 Blades manufacturing process scheme ........................................................................................... 42 Figure 42 Schematic of the 0.9 scale of the prototype without (up) and with (down) off-set. ...................... 43 Figure 43 Schematics of the end-plate of the prototype ................................................................................ 44 Figure 44 Sketch of the base where the end-plate is connected to the force balance ................................... 44
Table 1 Project objectives for the period ........................................................................................................ 13 Table 2 Part of the benchmarking table .......................................................................................................... 16 Table 3 Status of the SWT sector in Netherlands ............................................................................................ 17 Table 4 Economical aspects for SWT installation in Netherlands ................................................................... 17 Table 5 Meteorological profile of each pilot ................................................................................................... 25 Table 6 Applicability of design variables to different WTs .............................................................................. 41 Table 7 Experimental plan and outcome ......................................................................................................... 43 Table 8 Noise predictions for the three SWI wind turbines ............................................................................ 59 Table 9 Project meetings, dates and venues ................................................................................................... 76 Table 10 Deliverables submitted in the first project period ........................................................................... 77 Table 11 Milestones achieved in the first project period ................................................................................ 77 Table 12 Resources monitoring of the first period (CIRCE) ............................................................................. 80 Table 13 Resources monitoring of the first period (PPL) ................................................................................ 81 Table 14 Resources monitoring of the first period (KTH) ................................................................................ 82 Table 15 Resources monitoring of the first period (FORES) ............................................................................ 83 Table 16 Resources monitoring of the first period (METEODYN) ................................................................... 84 Table 17 Resources monitoring of the first period (KEMA)............................................................................. 85 Table 18 Resources monitoring of the first period (G!E) ................................................................................ 86 Table 19 Resources monitoring of the first period (SAL) ................................................................................ 87 Table 20 Resources monitoring of the first period (ULEEDS) .......................................................................... 88 Table 21 Resources monitoring of the first period (DARMS) .......................................................................... 89 Table 22 Resources monitoring of the first period (BAPE) .............................................................................. 90 Table 23 Resources monitoring of the first period (SOLUTE) .......................................................................... 91 Table 24 Resources monitoring of the first period (TCD) ................................................................................ 92 Table 25 Resources monitoring of the first period (Total) .............................................................................. 93
The Wind Energy Roadmap, which was published by the European Commission (EC) on October 7th, 2009, and was presented and discussed at the Strategic Energy Technology Plan (SET-Plan) workshop, will play a key role in fighting climate change and in helping EU Member States to meet the 2020 targets identified by the new RES Directive of December 2008, which sets the following goals for the wind energy sector:
A wind energy penetration level of 20% in 2020.
Onshore wind power fully competitive in 2020. 250.000 new skilled jobs created in the EU by the wind energy sector in the 2010 – 2020 period.
Currently, the major application of wind power is electricity generation from large grid-connected wind farms. However, following the changing trend of the energy sector from a centralized energy system to a distributed one, small wind systems and its hybrid applications are expected to play an increasingly important role in the forthcoming years, meaning a higher share in the energy generation. With the support of the smart grid technology and fostered by the directives and regulation associated to the sector, small wind turbines (SWTs) can now be connected to the electrical grid from the consumer-end and, little by little, contribute to the stabilization of the electrical grid. Due to this fact, small-scale wind energy has now been applied in fields such as mobile communication base stations, offshore aquaculture, agricultural and farming and sea-water desalination, among others, in several countries. Besides this scenario, the integration of small wind energy in urban and peri-urban areas is being a challenge due to the barriers the technology has at this stage of development.
SWIP objectives
The main objective of the SWIP project is to develop and validate innovative solutions for small and medium size wind turbines to improve their competitiveness, enabling and facilitating the integration and deployment into urban and peri-urban areas.
The new and innovative solutions will address the current barriers (turbulence, noise, vibration, aesthetic aspect, cost of technology, wind resource assessment, wind market, user friendliness, social acceptance and safety) that delay the market uptake of this technology. These solutions will: reduce the costs of the electric generator of wind turbines, providing two new concepts for energy generation; increase the Cp ratio of the blades, so that the number of hours that the SWT is producing increases by 9%, highly softening or even eliminating the mechanical and acoustic noise they currently produce; reduce the maintenance costs of the SWTs up to 40% by including two innovative elements (SCADA for preventive maintenance and magnetic gearbox) in the SWTs and improving the integration of the wind turbines in buildings and districts with more aesthetic solutions.
The project will develop three different prototypes to be integrated in three different scenarios (new energy efficient building, shore-line and industrial area), to validate the solutions and goals aimed, providing scalable solutions for different applications, covering several user needs.
Moreover, the project will improve the current methodologies for wind resource assessment into urban and peri.urban areas, reducing the RMS error in wind speed estimation until 8%, minimizing the risk and the opportunity costs of the small and medium size wind turbines when they are integrated in these environments.
Work performed since the beginning of the Project
The work performed in the first project period convers a period where some preliminary works and studies have been developed. Preliminary tasks within WP1, WP3, WP4, WP5 and WP7 have been completed to set the basis for the further development of the works. All work has progressed aligned with the requirements from the DOW with minor deviations without greater impact within the progress of the work.
All work packages have run simultaneously in this period. A total number of 12 deliverables have been submitted.
Main results achieved so far
Within WP1, a benchmarking of small and mediums size wind turbine technologies has been developed, collecting, assessing and comparing the main technologies, both at market and at prototype level, concerning small wind turbines. Moreover, energy plans in EU cities and an analysis of three relevant European cities have been performed in order to determine the possibilities and space the SWTs have within the future concept of those cities and particular restrictions for the demo sites.
Figure 1 Information sheet of the city of Rotterdam
Moreover, a design and performance evaluation methodology for permanent magnet synchronous generators to be used when designing optimal generators for small wind power applications in urban and peri.urban environments has been performed in WP3. The design method developed has been applied to design generators of 2, 4 and 20 kW, using real component characteristics and wind resource data.
A set of selection Guidelines (considerations and questions) for wind turbine and blade development such that they can more successfully be integrated into buildings, urban districts and other suitable areas is set out in WP4. The Guidelines address analysis protocols, decision making procedures and turbine/blade functionalities.
Within WP5, a selection of the most proper devices and tools for the Supervisory Control And Data Acquisition (SCADA) system is discussed. The new small and medium wind turbines, which will be developed in the project, have to bring along an economical and powerful SCADA system.
The electromagnetic compatibility requirements established by regulations emission and immunity requirements have been determined in WP7, collecting the reference standards where these requirements are set, and describing the test procedure which shall be performed in order to certificate the conformity of equipment under test. Furthermore, several electromagnetic disturbance mitigation methods which may be applied in case the equipment is not in accordance with the former electromagnetic requirements are approached.
The project’s website (www.swipproject.eu) has been created and published, having a private space for the internal project management.
Finally, a questionnaire has been developed and distributed among the consortium and has been published in the webpage which aims at providing information to investigate the training needs that the society demands/needs in order to get acceptance on SWT.
Expected final results
SWIP project sets up a comprehensive benchmark that includes the most significant European legal and technical frameworks regarding small wind energy turbines regulations, the generation technologies and the energy plans for cities.
The project will deliver a methodology for wind resource assessment in urban and peri-urban areas, able to predict wind speed in urban location, without the need of performing a measuring campaign, and to
implement such methodology in software. By means of that software the consortium will be able to assess and validate the accuracy of the model in the three locations in the project.
SWIP project has a clear orientation to small and medium wind power which involves:
The design of an innovative and low cost wind generator (between 1 and 100 kW) which could be adapted to different types of wind turbines deployments depending on its final emplacement. Two configurations of permanent magnet generator will be developed, one for direct drive connection and a second one for a gearbox connection. The design and development of cutting-edge technology wind blades, which maximize the wind energy conversion in each type of final model, addressing small and medium size wind turbines and considering both vertical and horzontal axis for different use. The new blades will also contribute to the objectives of reducing vibration and noise coming from those elements, addressing the overall operation goals established in SWIP. The implementation of a Supervisory Control And Data Acquisition (SCADA) system that will allow a better performance of the wind generator, through improved operation and maintenance. This system will be used for the control of the turbine, safety issues, operation mode selection and reliability improvement through preventive maintenance. Converters will be able to work both in isolated grid and connected to the network. Furthermore, their control will satisfy “The Network Code on Requirements for Generators” which will be certified once they are installed in their final locations.
The SWIP project will also analyze the structure and anchorage elements of small and medium size wind turbines for their installation into districts and buildings and it will develop best practices guidelines, for the aesthetic integration of these systems into urban and peri-urban settings. The project will also develop and implement solutions in order to mitigate and to absorb the noise and vibration produced by the wind turbine and to study the existing regulations regarding the safety issues in small wind turbine operation.
SWIP website
The Project website is www.swipproject.eu. The web page is regularly updated with information of the Project.
2. Core of the report the period: Project objectives, work progress and achievements, project management
2.1. Project objectives for the period
The project objectives for the first period with their related tasks are presented in Table 1.
Table 1 Project objectives for the period
Objective Task
Euro
pean
Fra
mew
ork
Asse
ssm
ent
To study the current available technologies and products regarding small and medium size wind turbines.
1.1
To analyse the economic and legal status of this sector, taking special care about the energy plans applied in the European cities, focusing mainly in the locations where the pilots are going to be installed
1.2
1.3
1.4
Deve
lopm
ent o
f in
nova
tive
solu
tions
fo
r ele
ctric
al
gene
rato
rs To select and optimise the final design of the PM generator by using 2D and 3D
FEM studies from different preliminary designs in order to optimise stator topologies for permanent magnet machine, which minimize the peak values of cogging torque allowing lower cut.in wind speeds and optimize the efficiency.
3.1
New
bla
des
desi
gn To assess their aesthetical impact and improvements in the design according to
aesthetic parameters before integrating them into the urban districts. 4.2
Cont
rol a
nd
SCAD
A sy
stem
To define the parameters, alarms and communication support that the new SCADA system will integrate.
5.1
Noi
se, v
ibra
tion
and
safe
ty
To assess the applicability of the current standards on noise and vibration to the field of small and medium wind turbines installed in urban areas.
7.1
To carry out a theoretical modelling of specific airfoils in order to mitigate the noise and vibration inherent to their performance as much as possible.
7.2
To analyse the current standards on safety aspects of SWTs. 7.4
2.2. Work Progress and Achievements during the Period
2.2.1. WP1. European framework assessment
Work package no. WP 1 Start: M01 End: M44
Lead Participant KEMA
Work package title European framework assessment
Activity Type Research activities
Participant involved CIRCE PPL FORES METEODYN KEMA G!E SAL BAPE
Person Month (Actual Period)
1.00 1.08 - 1.00 5.39 0.55 2.50 6.00
Person Moth (Actual Project)
1.82 1.23 1.91 1.00 6.41 0.82 2.50 6.00
Person Month (Total project)
3.00 3.00 2.50 1.00 7.00 2.00 2.50 6.00
Actual Period Actual Project Total Project
Total Resources allocated 17.52 21.69 27.00
2.2.1.1. Task 1.1. Benchmarking of small and mediums size wind turbines technologies
The main objective of this task was to have a general overview and benchmark of the technologies currently available. The aim of the benchmarking of small and medium size wind turbine technologies was to collect, assess and compare the main technologies, both at market and prototype level, concerning small wind turbines. Results of this task were included in the Deliverable 1.1: Benchmarking of small and medium size wind turbines technologies and legal framework.
The task 1.1 has been completed. The scope of the data has been broadly discussed among partners involved in this Task and later commonly accepted.
The document has been revised as to the contents by CIRCE and FORES, as to text by G!E and as to legal aspects by KEMA.
The range of small size wind turbines (SWTs) was divided into a few sub-ranges, depending on the rated capacity of wind turbines: 1.10 kW, 10.100 kW, 100.300 kW. Benchmarking took into account types of SWTs and technologies deployed. The result of the benchmarking of small WTs in groups is shown in tables in the Appendix, and a screenshot of a part of the table is presented below.
The spreadsheet includes a summary of product data for SWTs and calculated characteristic parameters. Parameters of WTs are divided into mandatory and non-mandatory data (depending on the availability).
Additionally to power coefficient and other parameters at the rated (design) conditions, important parameters for potential urban applications like output and productivity at average wind speed 4 m/s were collected and analyzed.
The main conclusions from the benchmarking study are: 1)Available data provided by WTs producers differ very much and parameters of WTs have different reliabilities; 2) There is lack of parameters describing small WTs for urban conditions, characterized by low wind speed, turbulence and variable flow conditions; 3) There is lack of noise data, especially for low-speed wind conditions; 4) Available WTs are characterized by high investment costs with a large spread of costs between models and types of WTs; 5) Problems with control of WT operation and connection to internal network and external grid are not solved.
Outcomes of the benchmarking study support planned activities within the project aiming at technological development and setting new practices in use of WTs in urban environments. This includes the modelling of wind conditions at WT locations, design of WTs which are better suited to urban environments, development of technology of WT components in order to reduce costs and make construction robust, and finally, the proper selection of WTs for operation at urban locations characterized by high energy generation, low noise and vibration and low maintenance costs.
No Picture Unit
Mandatory data1 Producer Vindcraft2 Model name ANTARIS 2.5 kW ANTARIS 3.5 kW Energy ball v2003 Orientation - horizontal upwind horizontal upwind horizontal upwind4 Blades - 3 3 5, spherical5 Rotor diameter m 3,00 3,50 1,986 Rotor height m7 Swept area m2 7,07 9,62 3,088 Rated output kW 2,00 3,60 2,25
9Rated windspeed m/s
12,0 12,020,0
10 Cut-in m/s 2,5 2,8 3,0Non-mandatory data
11 Contact home-energy.com
12 Country Sweden13 Peak output kW 4,00 7,0014 Cut-out m/s 13,0 13,0 26,015 Noise level dB(A) N/A16 Head weight kg 85 105 90
17Recomm. tower height m
10-15 12-1812/15
18 Price EUR 1050019 Powercurve N/A N/A N/A20 Power at 4m/s kW 0,15 0,2
For a high market penetration not only the technical aspects of the SWTs need to improve but also specific policies and regulations for SWT are needed. This seems justified because looking only at the urban wind potential numbers show that it can play a substantial roll in the future electricity market with a total installed capacity of 6,4 GW for the SWIP countries. Overall the UK seems to have the most favorable market outlook for urban wind with Ireland as runner up. There are many regulations, policies and standards that apply to the wind sector. It is clear that none of the SWIP countries did include urban wind in their 2020 targets. Policies and regulations are mainly lacking for urban wind turbines. The results of the benchmarking give broad information on basic parameters of the SWTs and this information is important for the project partners developing new SWT models for the pilot sites.
2.2.1.2. Task 1.2 Legal and funding status of the sector
There are eleven factsheets made of all the SWIP countries with the status of urban wind turbines, the legal status and permitting procedures, the urban area and maximum urban wind potential and funding status per country. Also an average wind speed figure per country is included in the factsheets. Examples of figures and tables in the factsheet of the Netherlands:
Table 3 Status of the SWT sector in Netherlands Status & targets Total wind UrbanInstalled [MW][2013] 2,434 1Number of turbines [2013] 1,950 400Target [2020] 6,000 -
Table 4 Economical aspects for SWT installation in Netherlands EconomicalFeed in tariff (2013) Max 9.5 ct/kWh for 15 yrsEnergy Investment Subsidy
44% tax reduction on the investment costs
Local Climate subsidy Depends on region/province
Figure 3 Distribution of the urban wind potential in Netherlands
Conclusions: there are many regulations, policies and standards that apply to the wind sector. It is clear that none of the SWIP countries did include urban wind in their 2020 targets. Policies and regulations are mainly lacking for urban wind turbines. In most SWIP countries SWT are treated economical equally as large wind turbines making it highly unattractive to invest in SWTs. For now SWTs seem to play only a roll in niche markets. For a high market penetration not only the technical aspects of the SWTs need to improve but also specific policies and regulations for SWT are needed. This seems justified because looking only at
the urban wind potential numbers show that it can play a substantial roll in the future electricity market with a total installed capacity of 6,4 GW for the SWIP countries. This installed capacity is calculated assuming a yield of 5MW per km2 of urban area at 10 m altitude.
2.2.1.3. Task 1.3 Energy plans for cities assessment
The aim of the task was to assess the main and most advanced cities in terms of energy plans, analysing the possibilities and space the SWTs have within the future concept of that cities. At least, three representative cities were supposed to be analysed in different climate areas, with the aim of having the most representative scenario for Europe. The results of this task were included in the Deliverable 1.2: a report on Energy plans in EU cities. The part of the report covering results of Task 1.3 described the energy plans in EU cities and analysed four relevant European cities. Partners involved in this task discussed main possible ways to evaluate cities energy plans and finally two were selected. The first one refers to available information on advanced European cities in the area of urban wind energy, used as examples of wind energy use in these cities. The second group includes cities from the project partners countries, proposed and selected by the project consortium. It has been decided that, at least, three relevant representative cities are analyzed. For the countries represented in the project, 3 coastal cities were selected and presented in information sheets (Nantes, Rotterdam and Klaipeda) and one inland city (Kaunas). These cities are located in characteristic locations for good wind conditions in Europe and are representative for their countries. Partners from the respective countries collected necessary data on the planning and WT issues for the report. The authors of deliverable D1.2 are: BAPE, SAL, DNV GL.
Draft document has been prepared by BAPE, SAL and DNV GL, internal review and contribution to the report was of CIRCE, SOLUTE and FORES, final revision by DNV GL and submission by CIRCE.
The analysis showed that there were hardly any examples of city energy plans taking into account the possibility of installing SWTs. Some EU cities mention SWTs in their municipality regulations, and also several local SWTs projects are being carried out around Europe. E.g. urban wind is mentioned by the local municipality regulations from a small Belgium city (Sint-Katelijne-Waver) and also the city of Berlin (Germany) reports on several urban wind projects. For Denmark, the Danish Energy Agency estimated that there are 3.000 households with SWT established. Local projects with SWTs involved cover several research areas from Micro Smart Grid initiatives to pilot projects on e.g. electric mobility and combined studies on ‘PV systems & SWTs’. A comprehensive database on EU cities undertaking actions against climate change is the “Covenant of Mayors” (CoM). Participating communes commit themselves to implement Sustainable Energy Action Plans, and the amount already exceeds 3.600 plans. SWT’s can be considered as being part of some of these plans (e.g. Cornwell County plan).
Conclusions drawn: It is of increasingly importance for city energy plans to take into account SWT solutions in urban planning. The productivity of SWTs heavily depend on the ‘micro conditions’ around the turbine (e.g. wind conditions at a given location, architectural and structural conditions of the building and environment), which only can be used in an optimal way when these are taken into account in the city energy plans (a city plan is able to focus on these ‘micro conditions’). Also the interaction with other developing energy technologies plays a large role in exploiting the potential of distributed SWTs. The amount of applications for SWTs increases due to this developing technology, where SWTs can be used in a combination with e.g. electric bicycles, city buses, street lighting, electric vehicles etc. Also a synergy for combined systems of PV and SWT offers partial solutions to intermittency problems of renewable energy sources. To benefit from these synergies, city energy plans need to take into account these possibilities and
chances for SWTs. These conclusions shall be taken into consideration when developing business plans for implementation of SWTs.
2.2.1.4. Task 1.4 Particular legal requirements for each demo-site
This task envisaged a site specific study of the legal and regulatory requirements which must be complied with in order to realise the demonstration installations at each of the 3 pilot sites.
This research was lead and compiled by Solearth and with major collaboration of BAPE. Along with the work of Task 1.3, it feeds into Deliverable 1.2 lead by KEMA. The work has been completed and delivered.
The study considered the precise location of each turbine its interrelationship with its context and adjacent buildings and structures, the height and dimensions of the turbines. The report states that “ .. the combination of sites and turbines proposed to be installed represents a wide spectrum of diversity in terms of application for urban and peri urban wind generators in Europe.” [p15]
The legal requirements were studied under the following framework;
Spatial Development Plan (Zoning) Planning Permission Building Approval Ownership and Title Noise and Vibration Environmental Impact Assessment Connection (to Grid) protocols) Operation Regulations
Specific limitation as to position, size, noise, vibration etc were characterised and documented and the process of showing compliance (applying for permission) or not was examined and also characterised at each location.
It was found that, while certain application or notification processes (to the local planning authority, utility agency, etc) must be processed in each location, no outright obstacles to installation were exist in the legal requirements applicable to each site. In the case of the 3 pilots, evaluation of these legal requirements does indicate that such turbines (size, type, etc) as envisaged by the SWIP project Description of Work will be legally installable.
These results now inform the work in WP8
2.2.1.5. Task 1.5 Social awareness and persuasion
Task 1.5 is focused on assessing the training and awareness needs of the public, for acceptance of Small Wind Turbines. The various technical and economic barriers that limit the uptake of SWTs are well known, as outlined in the project proposal, and this task aims to better understand the opinions that people have of SWTs, how interested they are in our proposed technology, and the messages that will be most persuasive to them.
Figure 4 Installation of a WT .Procedure to ask for permissions
As a first step in this process, a questionnaire was devised which takes account of the respondent’s socio-economic background, including age, income, profession and location, and investigates their awareness and attitude towards SWTs. The questionnaire was produced in English by G!E, and then translated into Spanish and Polish by CIRCE and BAPE, to be used at the demonstration sites. All three versions have been made available through the SWIP project website.
The questionnaire is multiple choice, so collects quantitative input only. Any sections requiring qualitative input would have necessitated translation, representing a considerable burden of work. Taking a multiple choice approach allows for the comparison of data from questionnaires in different languages.
Figure 5 SWIP project questionnaire
In the first period of the project, 197 online responses have been received. This has been supplemented by responses collected by BAPE and G!E at different events, bringing the total number of responses to 220. The DoW sets the target of 250 online responses, and it is possible that we will exceed this. A further 50 responses are expected from each demonstration site. This will need to be done in tandem with the demonstration phase of the project.
A preliminary examination of the collected data shows that most of our responses came from three countries: Spain, the United Kingdom and Poland, and that our respondents are mostly energy professionals, with tertiary education or above. It appears that, in terms of visual impact, SWTs are better accepted than large wind turbines, with the main concerns revolving around cost-competitiveness and performance. As a result, competing solutions, such as Solar PV, are viewed more favourably. SWTs have mostly been regarded as being suitable for industrial, rather than residential, areas.
There are no deviations from Annex I to report, and we expect no difficulties in achieving the aims of the task, and the final Deliverable, due in M44. However, we are aware that we need to expand the scope of the respondents, to avoid having input only from energy professionals.
As corrective action, we will need to work to ensure that we are not collecting information only from energy professionals, but also from the general public. The 150 responses from the demonstration site areas will provide good input in this regard. We will also reach out to citizens’ organisations and municipalities. In order to expand the geographic scope of the questionnaires, French and German translations are being produced by G!E, and will be implemented in the SWIP website.
2.2.1.6. Task 1.6 Scalability of the solutions
The task leader (PPL) has gather information on wind turbines to execute the task. This task needs the project to be more advanced to start working on the scalability of the solutions.
2.2.2. WP2. Wind resource assessment and urban models
Work package no. WP 2 Start: M01 End: M44
Lead Participant METEODYN
Work package title Wind resource assessment and urban models
Activity Type Research activities
Participant involved CIRCE PPL METEODYN SAL ULEEDS BAPE SOLUTE
Person Month (Actual Period)
10.22 0.00 20.79 1.50 9.00 6.00 0.00
Person Moth (Actual Project)
11.23 0.00 13.05 1.05 7.22 2.20 0.00
Person Month (Total project)
20.00 1.00 25.00 1.50 10.00 6.50 2.00
Actual Period Actual Project Total Project
Total Resources allocated 43.72 34.75 66.00
2.2.2.1. Task 2.1 Wind resource assessment in the demo-locations
The aim of this task was to manage a whole measurement campaign and wind resource assessment in each one of the three existing demo-sites.
Therefore, next activities were identifies in order to reach the considered goals:
A “Wind resource assessment for urban areas” guideline writing, including:
Parameters to be measured (including time span, sampling rate, etc). Meteorological sensors and devices required. Met mast configuration: discriminating “Roof” or “Ground” locations. General considerations for a “good practice” campaign.
Sensors and devices selection, purchase and installation:
A market research was developed, in order to select the most appropriated devices for the met masts, considering the particular requirements for each site.
Regarding the Polish demo-sites, two met masts have been constructed, which are placed in Choczewo and Kokoszki. The mast (3 m high) in Choczewo was constructed on the building roof, on 8th of July 2014. The meteo station consists of: 2 cup anemometers, 1 sonic anemometer, 1 wind vane, 1 temperature sensor, 1 humidity sensor, 1 barometer, 1 datalogger and 1 GSM modem. The data from the wind mast are collected following Guideline previously prepared. First results have been transferred on 8 of July 2014.
The construction of the met mast in Kokoszki –24 m high. was more complicated due to required building permission. The met mast has been constructed on 19th of March 2015. The station consists of: 2 cup anemometers, 1 wind vane, 1 temperature sensor, 1 humidity sensor, 1 barometer, 1 solar panel, 1 datalogger, 1 GSM modem and mast illumination. The data from the wind mast are collected following Guideline previously prepared. First results from the meteo station have been transferred on 25th of March 2015.
Figure 7 Meteo station in Kokoszki
In Zaragoza site, since the final location for the wind turbine was not defined, the mast was installed over the thermal chimney, located in the CIRCE´s building. It was erected on 13/06/2014. The met mast includes: 2 cup anemometers, 1 sonic anemometer, 1 wind vane, 1 thermometer, 1 barometer, and 1 datalogger. An “in situ” recording system (using a pc) was installed to store the measured data. At the moment, more than 9 months of measurements, including high and low frequency data, are available.
Measurement campaign follow up and Wind Resource characterization
Currently the three measurement campaigns are ongoing. The objective must be to extend the measurement period as much as possible, in order to obtain a better characterization of the existing wind resource at each demo-site.
Moreover, within the last months, measured data have been shared with task 2.2 developers, since they need the required input data for this task.
2.2.2.2. Task 2.2 Wind behaviour simulation in urban and peri-urban areas
Task 2.2 is focused on the wind resource simulation in the three pilot sites, these simulations are being performed with two different specific software. This will give the first approach on the differences between the simulations and the real scenarios.
1. Site and wind models
Each pilot site has been 3D.modeled (SAL, Meteodyn). Work has been done thanks to public data available on-line.
Figure 9 Choczewo 3D model Figure 10 Kokoszki 3D model Figure 11 Zaragoza 3Dmodel
The meteorological profile of each pilot site has been established, including a theoretical estimation of turbulence length scales (Meteodyn).
Table 5 Meteorological profile of each pilot
2. RANS calculations
First RANS calculations (UrbaWind) have been conducted on Choczewo and Zaragoza sites, focusing on the exact position of the measurement apparatus (Meteodyn). Kokoszki has not been calculated yet (the met mast installation was delayed).
Set-up and mesh have been realized for LES calculations ( Fluent) (ULeeds, Meteodyn).
Figure 14 Choczewo first LES results Figure 15 Zaragoza meshing
There are still some questions about mesh density and turbulence modelling for both sites: flow seems too few turbulent, and the mesh seems to be too fine, in order to find a correct solution.
2.2.2.3. Task 2.3 Improvement of wind resource analysis methodology
Task 2.3 aims to improve the current methodology with regard to the wind assessment in local environments. Doing so, the level of accuracy will increase, avoiding the need to perform a measuring campaign in locations where a SWT is going to be installed.
WRA generally uses long term data from a meteorological station and transfers these data to the wind turbine site (micro-siting). This transfer deals with orography and roughness, and depends not only on wind speed and wind direction, but also on atmospheric thermal stability, which is still roughly understood and modeled by scientific community. The idea within SWIP is 1/ to enhance our skills in CFD in order to take into account this thermal stability into our micro-siting tools, and 2/ develop a global methodology to feed these tools with historical data (how to assess thermal stability in the long term past meteorological data ?). The first point has been addressed.
Summary of progress towards objectives and highlights of most significant results
A systematic approach has been deployed on data measured on very large met-masts (200m in Cabauw, Netherlands, and 200m in Rödeserberg, Germany).
Figure 16 Cabauw area Figure 17Cabauw met mast Figure 18Rödeserberg area
These data allow constructing a stratified atmosphere model and to parametrize the corresponding layers in a k.L turbulent model for RANS softwares.
This work is going to be presented in the Intercontinental Wind Power Congress (Istanbul, April 2015) and we are going to discuss it at the 3rd International Conference on Energy and Meteorology (Boulder, June 2015).
2.2.2.4. Deviations from Annex I and corrective actions:
One of the demo sites mentioned in the initial DOW was changed: from Borkowo to Kokoszki due to after an evaluation of both sites, Kokoszki turns out as the best of both demo sites.
The Description Of Work included a sonic anemometer for each demo-site, but it was not initially considered in the proposed budget. Therefore, it was added to the modified budget with an amendment. However, finally it was not included in Kokoszki site, since according to its surrounding orography and obstacles, relevant turbulence and/or vertical wind are not expected. Barometer was not included in the initial budget (for Polish met masts) but it is indeed a sensor needed, so it was finally included too.
The met masts erections were delayed due to several causes: devices purchase, building licenses, etc. However, it did not affect to the expected results, since a long enough measurement campaign is been developed at the moment.
Kokoszki has not been calculated in task 2.2 yet (the met mast installation has been delayed). In addition, Kokoszki won’t be addressed with LES since the wind turbine is far away from the buildings: the interaction is too weak to require such a detailed modelling as LES. This decision has no impact on the project objectives.
Within task2.3, improvements foreseen at the beginning of the project (Annex I) were specially focused on local enhancement of CFD modelling, thanks to accurate and detailed results from LES and measurements. For the moment, data (both in LES and measurements) are less dense than planned. So, another way to improve Wind Ressource Assessment has been identified and implemented: thermal stability.
Depending on the quality of the results of task 2.1 (measurements) and 2.2 (LES simulation), some improvements can still be done in the second half of SWIP project within Task 2.3.
2.2.3. WP3. Development of innovative solutions for electrical generators
Work package no. WP 3 Start: M01 End: M44
Lead Participant CIRCE
Work package title Development of innovative solutions for electrical generators
Activity Type Research activities
Participant involved CIRCE PPL FORES DARMS
Person Month (Actual Period)
27.00 0.37 - 13.50
Person Moth (Actual Project)
18.74 2.00 14.01 14.07
Person Month (Total project)
36.5 2.00 18.00 35.50
Actual Period Actual Project Total Project
Total Resources allocated 40.87 48.82 92.00
2.2.3.1. Task 3.1 New modular PM generator design
This task aims to design three PM generators. The work done within this task has led to the achievement of the milestone MS5 “Designs and FEM Models of SWIP generators”. The actions performed towards the achievement of the task goals, and the results obtained are detailed on the deliverable D3.1 “Design and FEM Models of SWIP generators”. The design method developed has been applied to design generators of 2, 4 and 20 kW, using real component and wind resource data available at that moment.
As a starting point, the current state of the art on Permanent Magnet Synchronous Generators (PMSG) has been analysed, obtaining an estimation of weight, dimensions and performance characteristics for PMSG from 1 to 100 kW. This stage allows comparing the new generator designs against the technology that is currently on the market.
In order to achieve several preliminary designs of the generators to analyze and chose the most optimal, a new analytical tool named SWIP PMG Sketch has been created. The tool is capable of obtaining up to 500.000 high-efficiency generator designs meeting the designer technical requirements, which are typically imposed by the wind turbine components (converter, blades, control...) in order to obtain good compatibility. When the generator operates outside its rated conditions, efficiency can be noticeably lower than rated. The performance of every preliminary design is automatically simulated by the software in all its operating conditions, ensuring the most optimal design among all obtained is selected.
After one preliminary design is selected, FEM models of the designs are generated to study the magnetic and structural behaviour of the design during operation. Further thermal and electric studies are performed aiming to ensure the reliability and security of the design, helping to size insulating systems and heat evacuation systems, if necessary. The actions performed during the design stage are summarized on the figure below:
Figure 21 Design procedure and studies performed to validate the selected designs
The three PMSG designed and presented on the deliverable meet the main goals set within the SWIP project, regarding generator design: generator cost and magnet usage reduction, cogging torque peak and ripple minimization, and harmonic distortion decrease. Both generator cost and magnet usage reduction objectives are achieved due to PMG Sketch, which allows selecting the most economical design, and setting the desired magnet height as an input on the design process. The raw material costs for the designs are between 2 and 4 €/N·m2, while the magnet content reaches between 7.75 and 11.30 gr/N·m. On the other hand, cogging torque peak and ripple values are dependent on the relationship between number of slots and poles of the design. If the greatest common divisor is low, the peak value is reduced, but the torque ripple period increases. Therefore, care shall be taken when selecting the most optimal pole and slot number. It has been studied prior to the design, leading to the obtaining of designs with extremely low cogging torque (< 1N/m), which allow low cut.in speeds, and improves current market technology capabilities. The torque ripple in all designs is between 0.8 % and 1.5 %, improving the 5 % torque ripple goal set within the task.
2.2.3.2. Task 3.2 Technique for post-assembled magnetization of PM generators
One of the main objectives of Task 3.2 is to explore and propose an enhanced solution concerning manufacturing and structural design of electrical machines. These solutions will take advantages on manufacturing technologies available nowadays to be applied in a novel machine design. During the first stage of the task, the state of the art in cutting, locking and winding techniques of stators has been explored. Nowadays, distributed winding motor are widely used, in which the coils are wound in advance and then, they are inserted inside the stator slots. This winding technique is usually done manually increasing the development times and the manufactory costs, besides problems with the end coil length appear, resulting too long.
2 The volume and cost of the generators designed is proportional with the generator torque, therefore torque is used as normalizing unit.
Research concerning manufacturing process based on concentrated winding method is gaining importance, especially in low power motors. Due to the coils of the concentrated winding stators are directly wound onto insulators covering the stator tooth, they will be shorter than the coils of the distributed winding stators. Furthermore, higher space fill factors could be achieved. A general scheme of multibody concentrated winding stator (MCWS) design can be observed in Figure 22. Many attractive advantages of concentrate winding designs can be highlighted, such as, short winding end regions, short manufacture periods, low fault probability of turn-to-turn short circuit and less resistance losses, making it suitable for applications with high requirements of volume, weight and cost. However, this kind of technology presents several drawbacks, such as, high noise and high vibration due to the loss of circularity of the core inside diameter (Figure 233). Besides, it has the disadvantage of increasing elements of the stator, which is translated in higher manufacturing costs and complexity.
Figure 22. Assembly of modern segmented stator with concentrated winding.
Figure 23. Assembly of modern concentrated winding motor.
For this task a segmented stator design is proposed, where the tooth is designed in a way where no magnetic flux circulates through the back yoke, thus back yoke can have solid structure instead of laminated, reducing the manufacturing and assembling complexity of a laminated-joining. The back iron is generated by assembling all the teeth into the solid back yoke. Figure 24 shows a potential design for this kind of concentrated winding motor. The tooth is designed with the best shape to draw out the required performance, maintaining efficiency of the motors and the rotation characteristics such as the cogging torque. The proposed concentrated winding motor design ensures the circularity of the core inside diameter. Furthermore, a flexible back yoke will be properly designed to allow radial displacement due to pressure generated during the insertion of the stator into the motor housing, inducing this way tangential
pressure between the interface tooth-tooth avoiding undesirable gaps that may increase losses and reduce motor efficiency. Different designs will be analyzed using finite element software. The gap effects (location, thickness) located in the interface between joins over the machine performance will be assessed.
Figure 24. Proposed teeth . back iron solution.
2.2.3.3. Task 3.3 Magnetic gearbox
The aim of the task is to develop a novel topology of magnetic gearbox (MG). The initial proposed design consists of a high speed shaft, which is composed by permanent magnets, and a low speed shaft which is composed by coil windings. In order to improve the performance and efficiency of the magnetic gearbox, an exhaustive analysis of the selected topology will be performed; in particular, flux density waveforms, torque transmission and the torque ripple, will be checked and analyzed. At the beginning of this task, a transmission ratio of 1:4 and a torque value of 1600 Nm were stablished, according to the 20 kW prototype design. The maximum torque value has been defined according to flexural strength limit of blades. Initially, a bibliography review about the actual state of the art of magnetic gearboxes has been performed. Despite the higher manufacturing costs of the magnetic gearbox compared to traditional mechanical transmissions, MG can result economically viable due to the lower maintenance requirements during wind turbine operational life. Another important advantage of these kinds of transmissions is the zero wear suffers by its components, the reduced heating and acoustic noise and minimum vibrations. All these characteristics improve the reliability of the system.
Today technologies are focused on field modulated magnetic gears (MMG) and magnetic planetary gears because these solutions provide the highest torque density (50.150 kNm/m3), providing competitive performance in comparison with mechanical transmission systems (100.200 kNm/m3). Magnetic planetary gearbox (MPG) operates like a mechanical planetary gearbox, except that it is contact-free and needs no gear lubrication. Hence, it has the same characteristics of three transmission modes, a high-speed-reduction ratio, and high durability. The most modern MPG arrangement with Nd–Fe–B magnets is as shown in Figure 25(a). The gear combines the structure of a mechanical planetary gear system with the transmission principle of magnetic spur gearing ¡Error! No se encuentra el origen de la referencia.25(b). In the other hand, we have the modulated magnetic gears (MMG) whose assembly and transversal section are presented in Figure 266. These were initially designed for compact harsh environment typical of oil well logging tools. Fundamental to the operation of the MMG is the modulation of the magnetic fields produced by each of the permanent magnet rotors by means of the ferromagnetic pole-pieces.
Figure 25 (a) Magnetic planetary gear. (b) Magnetic spur gearing
Figure 26. Modulated Magnetic Gear design.
Initially, the magnetic gearbox proposed in task 3.3 is a parallel axis magnetic gear box as shown in Figure 2727. This MG has been modelled in the finite element software FEMM 2D. From this analysis, it was concluded that the MG dimensions needed to provide the design torque are very high, resulting in unacceptable torque density values. Furthermore, this MG configuration has a typical torque density value of 11.6 kNm/m3; in fact, the proposed design has a torque density value of 0.63 (5) kNm/m3.
2.2.3.4. Task 3.4 Development of a high coercivity materials with zero or drastically-reduced heavy-RE content
During the reported period the efforts in this task were focused towards fulfilling the following objectives:
Objective 1: Improved grain-boundary diffusion processing (GBDP) for minimising the amount of HRE used to increase the coercivity of Nd-Fe-B-based magnets Objective 2: Reducing the grain size of Nd-Fe-B magnets while avoiding problems with oxidation Objective 3: Development of Nd-Fe-B magnets with novel coercivity-enhancing grain-boundary phases
Work done on hot-compacted and die-upset Nd-Fe-B magnets
The grain-boundary diffusion process in Nd-Fe-B permanent magnets has been studied in order to reduce the amount of heavy RE element Dy without sacrificing the magnetic properties- DyF3 doped hot-compacted and die-upset Nd-Fe-B magnets were processed using hot-press. Corresponding magnetic properties and microstructure have been investigated using Permagraph, Vibrating sample magnetometer and Scanning electron microscope respectively.
On 31/01/2014 a Skype meeting was organized involving attendants from CIRCE and DARMS, in order to design the 2kW generator, various magnet characteristics had to be defined. Scientific as well as technical challenges in terms of magnetic properties and geometry of required permanent magnets were discussed as well as the relationship between magnet cost and performance to meet the requirements of SWIP project.
The effect of post-heat treatment (annealing) on magnetic properties and microstructure of Dy-free nanocrystalline hot-compacted Nd-Fe-B magnets have been also studied in order to find the optimum conditions (in terms of avoidance of coercivity loss due to the grain growth at elevated temperatures) for amicrostructure as well as the coercive field remained unchanged. As the next step, heat treatment for 8
ing Dy diffusion in DyF3 doped die-upset magnets. The results show a reduction in the maximum energy product and coercivity with nearly unchanged remanence.
Eddy currents losses in magnet material caused by its finite electrical resistivity play important role in efficiency of permanent magnet motors and generators. In order to understand the evolution of electrical resistivity for different processing routes, the effect of degree of deformation and DyF3 content on the electrical resistivity in nanocrystalline Dy free and Dy doped Nd-Fe-B magnets has been studied. Thin lamellas were cut out of hot-compacted and hot–deformed magnet samples and electrical resistivity has been measured by for-point method from room temperature up to 120° C.
On 06/06/2014 DARMS attended meeting with project partners in Zaragoza, where progress on the development of the corresponding tasks in WP3 was discussed. It has to be emphasized that final specifications of magnets which DARMS have to provide for the prototype permanent magnet generator are necessary from partners in order to meet the relevant milestones.
Figure 28 Hot-compacted and die-upset Nd-Fe-B magnets process scheme
Work done on sintered Nd-Fe-B magnets
The next aspects have been studied:
Preparation of precursor and green body – optimal ball milling parameters, grain size, impurities, oxidation Shrinkage of green body during the sintering – 25 % along the easy axis and 20% along the hard axis Quality of the sintered magnet – texture homogeneity, porosity Grain-boundary diffusion process in Nd-Fe-B Magnetic properties and microstructure
Based on the obtained results, DARMS was able to produce sintered Nd-Fe-B magnets with 3at. % Dy with the magnetic properties required by CIRCE.
DARMS has developed a routine for production of permanent magnet segments with the dimensions specified by CIRCE.
The first 10 segments were tested and can be delivered to the project partner for initial tests.
It is planned to provide with a total of 82 segments (72 required for the generator and 10 for testing and as spare) to the project.
Figure 29 Sintered Nd-Fe-B magnets with 3at. % Dy Figure 30 Nd-Fe-B magnets properties
2.2.3.5. Task 3.5 RE-free magnets
This task aims to generate new classes of RE-free permanent magnet, with both conventional and new architectures and morphologies, widening the possibilities for design of electrical motors, actuators or generators.
Fe-rich and Co-rich alloys are very promising candidates for rare-earth-free magnetic materials, but most of the iron and cobalt based intermetallic compounds have highly symmetric cubic phases, which leads to low anisotropy and low coercivity as a consequence. However, under pressure materials may undergo a structural phase transition and completely new high anisotropic ferromagnetic phases can be synthesized.
The ultimate goal is to use high-pressure/high-temperature to synthases new binary intermetallic compounds with CaCu5 structure. These intermetallic compounds do not exist at ambient pressure, but according to the theoretical calculations using the WIEN2k package, the CaCu5 structure could be stabilized under high pressure. To synthases the new binary intermetallic compounds from mechanical alloyed systems is expected. The gained knowledge will be used in the search for new, high anisotropic, rare-earth-free magnetic phases which would be of a great fundamental as well as practical importance.
Figure 31 Large volume cell for high pressure high temperature synthesis
So far, experiments on non-equilibrium synthesis of metastable alloy phases in BiCo5 and BiFe5 compounds have been performed. For this, two non-equilibrium synthesis tools have been combined: mechanical alloying and high pressure synthesis. Mechanically alloyed BiCo5 and BiFe5 samples were prepared by
milling in heptane for 12 h in P6 planetary mill and were used as precursor for high pressure synthesis. The HPHT synthesis was performed at DESY Hamburg. The precursor was compacted in multi anvil cell under pressure of 15.6 GPa and heated at 850° C for 30 minutes. By energy-dispersive x-ray microanalysis the presence of new metastable 1:1 BiCo phase was found in the BiCo5 sample. This was further confirmed by magnetisation and X-ray measurements.
Figure 32 Microscopic images of precursor and sample after HPHT synthesis
The experimental data confirm that the proposed synthesis routine is working and new intermetallic phase was received. However the method has to be modified. Dry high energy ball milling should be used in order to prevent oxidation and improve the precursor quality. Therefore a new SPEX 8000 mill was bought within the project.
Figure 33 New SPEX 8000 high energy mill
As next step, to performer HPHT synthesis on BiCo and BiFe binary systems at high pressure and high temperature is intended. The new precursors (described below) will be compressed at 15 GPa and heated for 30 minutes up to 400 °C and 800 °C. The phase content will be verified for each temperature and the structure of novel HP intermetallic phases will be accurately analysed. Further, examine the recoverability of new HP intermetallic phases to ambient conditions is planned, as well as to determine their compressibility (volume/pressure-dependences) upon decompression.
The proposed experiment is scientifically relevant:
1) from fundamental perspective, it would provide us the first information on possible pressure-induced transitions in binary Bi-Co, Bi-Fe systems and give an opportunity to construct their first P-T phase diagrams;
2) from perspective of applied science, we expect to synthesise novel HP intermetallic phases with high polarisation and high anisotropy which can result in their extraordinary magnetic properties. These phases could be further engineered in a rare-earth free magnetic material.
Participant involved CIRCE PPL KTH METEODYN SAL ULEEDS SOLUTE
Person Month (Actual Period)
1.00 5.09 0.00 5.65 3.00 18.44 21.40
Person Moth (Actual Project)
0.63 13.73 1.67 6.67 4.00 34.51 9.82
Person Month (Total project)
2.00 57.00 2.50 10.00 4.00 42.00 25.40
Actual Period Actual Project Total Project
Total Resources allocated 54.58 71.03 142.90
2.2.4.1. Task 4.1 CFD analysis and models for blades design
Task 4.1 aims to deliver a first design of the blades analyzing their performance and noise generation by means of CFD analysis, in addition, an optimization of these designs may be achieved during the WP duration. The first designs have been made by SOLUTE and the results can be seen in Annex I. This will be part of D4.1 that is due for M21 (second project period).
CFD analysis and models for blades design
CFD analyses have been performed on the initial designs of the three prototype turbines made by SOLUTE. The work has been carried out in consultation with work package leader and partners and has been divided into two categories:
(a) 2D simulations: (i) Study of sensitivity of the performance of the selected aerofoils to contaminations (ii) Analysis of the flow structures around the vertical axis wind turbine blades
(b) 3D simulations of the flow around the blades of horizontal axis wind turbines.
(a) 2D simulations: This part of the work has already been completed for the horizontal wind turbines and the simulation for V2 is on-going. The simulations were initially validated by means of the available data in the literature for the test case with a smooth surface. This was an essential step in order to verify the applied numerical model, domain and mesh size. After the simulation criteria have been established, the critical value and location for roughness on the surface of the aerofoils have been studied (Figure 34). The importance of wind turbine power reduction due to building up of this roughness has been addressed. Finally, suggestions have been made in terms of maintaining the rated power for the turbines over a longer period of time.
Figure 34 Variation of the lift coefficient (Cl) as a function of K/c for K: Critical value and c: chord length
In terms of the vertical turbine, as the rotating mesh frame in unsteady mode was required, it was dictated to carry out the 2D simulation rather than the 3D simulation due to the time constrains of the task. Since the aspect ratio of the turbine blades was high (span/chord: 15) the 2D simulation can provide a good estimation of the flow structure around the blade. The simulation domain and meshing have been completed (Figure 35) and the simulations for different wind conditions are at present in progress.
Figure 35 2D mesh with rotating core (green area) for the V2 wind turbine
At the same time, the preparation of the report for the 2D study is in progress.
(b) 3D simulations: Geometry preparation and hybrid meshing of the H30, H20 and H4 wind turbines have been completed (Figure 36). Preliminary simulations for the original 30 kW (H30) wind turbine have been carried out (velocity vectors and pressure contours were illustrated in Figure 37). Then the H20 turbine has been modelled for two typical wind conditions, i.e. average wind speed at the Kokoszki site and the rated wind speed. Some preliminary results for velocity and pressure fields for the H20 turbine blade were presented in Figure 38. Modelling of the H4 wind turbine is in progress. At the end of the simulations it is expected to provide a detail structure of the flow around the entire blades as well as an assessment of the aerodynamic performance of the blade to provide a feedback on the wind turbine designs.
Figure 36 Hybrid mesh for the H30 and H20 wind turbines
Figure 37 Relative velocity magnitude vector (left) and static pressure contours (right) around the aerofoil for the H30 wind turbine
Figure 38 Relative velocity magnitude vector (left) and static pressure contours (right) around the aerofoil for the H20 wind turbine
2.2.4.2. Task 4.2 Aesthetic aspect of vertical and horizontal blades
The task envisaged a comprehensive study of the aesthetic aspects of urban scale wind turbines, their varying aspects, and guidance for how to decide whether and how to install them. This has been carried out and documented as Deliverable “D4.2 Aesthetics recommendations for blades and methodology” delivered in Month 17. Solearth worked in three ways to explore, typify and then create framework for the wind turbines at both a specific (the pilot sites) and a generic level. A large number of design explorations to find the possibility of architecturally integrating the demo site turbines into the pilot buildings was carried out and this fed into the task.
Figure 39 Examples of architectural integration at Choczewo pilot site
In addition, precursor knowledge on what issues arise with siting and making decision as to colour, and form of (admittedly) larger wind turbine were consulted and their methodology and logic borrowed and developed to apply to small scale urban wind generators. Finally bespoke and original study methods (for example superimposition, using photomontage techniques, of variations in potential solutions to siting, connecting, colour, form etc) on real street typical streetscapes and general conclusions were drawn.
Table 6 Applicability of design variables to different WTs
.
PPL contributed real work examples and technical experience of colour and materiality in producing and maintaining real turbines as well as assisting with the structure and logic of the guidelines.
The work will be useful for the larger Guidelines in WP 6 also.
2.2.4.3. Task 4.3 Pitch control, yaw system and manufacture process for SWT blades
This task deals with three differentiate parts, two related with the wind turbine elements (pitch control and yaw system) and one related to the methodology to be followed to prepare the manufacturing process for the blades.
Regarding the passive pitch design, H20 WT is the biggest wind turbine to be installed in the demo-sites, due to its characteristics; the pitch needs to be designed in accordance with inertial, aerodynamics and structural characteristics of the rest of the WT components (power train, blades, generator, etc.). So far, the design of the H20 prototype has been performed and it’s ready for the manufacturing process.
With regard to the yaw system, both H4 and H20 wind turbines are going to need the yaw system for wind facing. A passive yaw system has been designed for the H4 and it is ready to be manufactured. Concerning the yaw system for the H20 wind turbine, a study on the possibility of design a passive yaw system has been considered but after first outcomes, this possibility has been dismissed due to the high weight of the resulting yaw system. The final decision has been to go through an active yaw system. This system is currently under development, the parts that will come out of the design will consist not only in the mechanical design but also in the control and sensors needed for the yaw system behavior.
The manufacturing process of the wind turbines follows the next scheme:
Figure 41 Blades manufacturing process scheme
The 3D files are going to be ready just after the end of the wind tunnel tests (T4.4), loads and structure calculations. For the final version, couple tests more will be needed, then these final versions will be used for production. All information will be documented in the production and the final methodology for the blades manufacturing will be delivered.
2.2.4.4. Task 4.4 Wind tunnel testing of scale models
This task aims to assess the performance of the blades at scale laboratory, serving as first approach of its behavior prior to be installed in the demo sites.
The tests will be performed with the focus on air flow around the tip of the model blades (last 17%) in order to gather information relating blade tip power losses and vortex shedding.
It was proposed to scale down the H4 model to 0.9 of the full scale in order to minimize wind tunnel blockage effect. Two blade tip configurations, i.e. (a) with (the original design) and (b) without the offset of the tip (Figure 42), will be examined in order to investigate the significance of the tip offset in the design. The experimental methods have been discussed with the involved partners (SOLUTE, PPL, TCD, METEODYN, KTH and CIRCE) through a number of conference calls. Particle Image Velocimetry (PIV) or high speed camera (tip vortices observation) and force measurements will be performed. The PIV system is already owned by the USFD. A suitable load cell has been chosen and purchased corresponding to the range/order of forces acting on the prototype and required resolution.
Figure 42 Schematic of the 0.9 scale of the prototype without (up) and with (down) off-set.
Since the design concept and the shape of the tip of H20 and H4 turbines are the same, and the V2 turbine also employed the sweep blade design, it is expected that the information gathered from the experimental tests using the scaled H4 blade tip will give indications of the performance of the blade tip of other two turbines, although the flow structure of the V2 may be more complex.
The prototype will be tested with different wind speeds to investigate the dependency of blade tip aerodynamic performance to Reynolds number so that the results may be useful for all three turbine designs. The plan of the experiment is presented in Table 7.
Table 7 Experimental plan and outcome
Velocity range (m/s) Re (×10^5) Particle Image
velocimetry (PIV)/High speed camera
Force measurement
10 1.43 N Y
15 2.15 Y Y
20 2.86 Y N
Outcome Aerodynamic performance sensitivity to
Reynolds number variations Monitor flow structure
at the tip Establish the forcesacting on the blade
The overall design of the test campaign has been completed and the drawings of the test parts (prototypes, end-plates and the base are shown in Figures 42 to 44) have been prepared and delivered to PPL for manufacturing. As soon as the parts are delivered the experiment can be started.
Figure 43 Schematics of the end-plate of the prototype
Figure 44 Sketch of the base where the end-plate is connected to the force balance
At the end of the experiment, it is expected to establish the structure of the flow around the tip of the blade as well as the force acting on it.
2.2.4.5. Task 4.5 Structural and durability analysis
This task aims to perform the structural analysis of the blades as well as the stress and fatigue analysis. Within this task, three different and complementary activities have and are being developed. These tasks are:
1. Blades design. In general, the design of the blades has been developed including all the aerodynamic parameters, and is currently in charge of the structural analysis and the complete definition of the composite lay-up and materials to be employed in manufacturing. The methodology employed followed the theoretical design of the three wind turbines suited to the specifications for small size and the urban wind environment. For each blade type, a set of aerodynamic profiles have been design following state-of-the-art procedure for wind turbine rotor design. As a final result, these sets of profiles led to a complete 3D design of the blades.
2. Wind turbine loads assessment. Dimensioning loads for the wind turbines based on the IEC rules have been determined, by an analytical approach and using the WT parameters so long defined. Extreme and fatigue equivalent load are assessed. These loads will be employed in the structural analysis of blades.
As one of the main issues regarding the wind turbines design, loads calculations must be obtained in order to define the requirements for the structural and mechanical designs. Our WTG loads and dynamics team identified all possible standards and regulations to follow and whether or not the loads must be dynamically calculated. After a tradeoff between the alternatives it was chosen the IEC61400.2 ed3.0, following the “Simplified Loads Methodology”, that is the most appropriate approach given the design status of the project.
However, a more detailed methodology has also being implemented, as an aeroelastic model of the horizontal wind turbines have been created. It is very useful to define and analyze the pitch behavior and will also help with the loads calculations, as long as it will double checks the analytic methodology followed to obtain load envelopes.
3. Blades structural analysis. Once the effective geometry is defined, and loads are also determined, SOLUTE has worked, and is also now working on the materials and composite lay-up definition of the blades. Structural analysis is made by means of an ABAQUS FEM model of the whole blade for each WT type. These models are at present built up and are now been used in an iterative process of calculation and results evaluation that will converge in a definitive composite lay-up that fulfill all strength requirements. Now H4 and H20 (medium and big size horizontal wind turbines) are close to a final lay-up definition.
Among all work done within this task, the next results can be highlighted:
3D CAD geometry of the three types of blades according to each WT operation condition.
Set of loads acting all over each type of blade, used for structural analysis of the blade.
Set of wind loads acting on each WT that will be used for structural analysis of the WT Nacelle, drive train and tower.
FEM model of the blades: ABAQUS detailed model with the geometry meshed in shells, the different properties (set of composite lay-up) for each radius, and loads applied also on different radius according to loads determined.
Structural analysis: results and its analysis at different development stages. Each status results are revised and evaluated for new proposals in search of the best structure (composite lay-up) of the blades. These proposals will be implemented in successive FEM models in an iterative process still under development.
In this task the PPL will manufacture the blades for 1.3 kW (V2) wind turbine. After an iterative process of analysis of the blades/generator/structure of the wind turbine with the demo site roof characteristics, the final design of the blades is about to be defined. Due to this process, the manufacturing of the blades has not started yet. In any case, primary lamination layers have been developed. The lamination schemes will be updated after the loads and structure calculations. Once laminating the first item and breaking it, the lamination layer scheme will be finalized or updated.
So far, the designs of the blades are already finalized (Figure 45) and the scheme for the lamination layers are in its second version.
Figure 45 Vertical wind turbine blades sketch
2.2.4.7. Task 4.7 Horizontal axis blades
This task aims to manufacture the blades for two wind turbines 3.5kW (H4) and 20.30 kW (H20). The blades to be manufactured for both WT prototypes will have the same design but the H20 blades will be scaled up from the H4 blades. The final designs of the blades (Figure XX) are finalized but still some extra tests are to be done in order to secure the final design. In any case, primary lamination layers have been developed. The lamination schemes will be updated after the loads and structure calculations. Once laminating the first item and breaking it, the lamination layer scheme will be finalized or updated.
In addition to the design and the primary lamination schemes, the connection of the blades with the hub has been done (Figure 47).
Figure 47 Connection of the blades with the hub
Also, the root of the blade (Figure 48) was modified for better connection with the hub and to have stronger blade. The blade root will be manufactured on fiberglass in order to reduce the weight and the price for the blades.
2.2.5.1. Task 5.1 Definition of parameters, alarms, communication, operation, and maintenance of the SCADA
The aim of this task consists in determining the most suitable tools to develop the SCADA systems for the small and medium wind turbines that are being developed within the SWIP project. This task finished having as outcome “D5.1 Definition of parameters for SCADA and alarms assessment” where all chosen tools can be found. These tools will be the “development environment” to form the SCADA within task 5.2.
As the SCADA requires a complex implementation, several issues had to be considered (in figure below). All of them had to fulfil the cost constraints. Besides, all elements had to be able to perform the SCADA tasks with enough precision.
A brief summary of the addressed issues are listed below:
FORES has defined the parameters which have to be monitored (see the table below) FORES has selected the most appropriated sensors to measure the required magnitudes to monitor a small wind turbine. These measures are useful not only for the SCADA system but also for the inverter which has to be developed in task 5.3 CIRCE has established a hardware architecture to the SCADA CIRCE has decided to use a communication protocol to transmit data from the different sensors to the SCADA’s core CIRCE has designed a software architecture to the SCADA’s interface in order to assure a multiplatform SCADA CIRCE has chosen the most suitable software tools in order to implement all required functionalities (operating system, database, programming languages and web server)
The most proper selection for each case has been made, taking into account that all these elements must work interconnected. Using these tools, the SCADA system will be developed with the maximum technical guarantees.
The chosen devices and tools to implement the SCADA system are listed below:
With regards to the required sensors, voltages will be measured through a custom designed board, whereas different commercial sensors will be used to acquire the rest of the magnitudes.
The communication from different sensors to the SCADA core will be carried out using a communication protocol: Modbus and RS.485 as physical layer.
Regarding the hardware architecture, the selected scheme is shown in the figure below.
Figure 50 Hardware architecture scheme
In order to implement the acquisition board, the selected board is an Arduino. Besides, a Beagleboard Black will work as the SCADA core.
Finally, the most suitable software tools have been chosen. This selection has several issues, which are listed below:
Operating system: a Linux distribution called Debian Relational database: a community-developed fork of MySQL called MariaDB Interface: the most used tools in Internet as HTML, CSS and JavaScript Web server: Apache or Lighttpd server in case the SCADA system lacks of memory Programming language: C for tasks which have to be executed continuously and PHP for tasks related to the interface
2.2.5.2. Task 5.2 SCADA development and integration
The aim of this task consists in making a SCADA system following the conclusions obtained in task 5.1. Two main works must be performed into this task, the hardware implementation, including the required self-made boards, and the software implementation, where it is necessary to include several developments.
Previous tasks can be divided into different sub-tasks, which are listed below:
Hardware: o Sensors and transducers must be bought o Self-made boards have to be designed and made o Commercial boards and the required connectors must be purchased
Software o Communication protocol has to be implemented
o SCADA’s interface must be designed and implemented o Deciding the necessary processes in the SCADA’s core o Code with regard to all processes has to be implemented
Additionally, a set of tests will have to be performed in order to check the right coordination among all components in the system.
FORES is designing the self-made boards in order to adapt all sensor signals to the required format.
CIRCE has defined all necessary processes for the SCADA’s core and the SCADA’s interface. This is an initial selection but it can change to improve the SCADA performance, to increase the functionalities or to achieve another advance. The first selection is listed below:
SCADA’s core o Data acquisition o Production control o Set values o Alarms o Calculation
SCADA’s interface o Communication using XML o Calculation o Input
Now, the works are focused on the code development for the SCADA´s core as well as the implementation of the communication protocol.
2.2.5.3. Task 5.3 Design of the converters and controls for the wind generators
With the aim to adapt the variable conditions of the permanent magnet synchronous generator (PMSG) to the stable conditions of the grid, in task 5.3, a full converter is set between the low-voltage grid and the PMSG. This full converter is composed of two power converters, able to manage and adapt the power from the PMSG to the grid. These two converters are called VSC Controlled Rectifier and VSC Controlled Inverter.
VSC Controlled Rectifier
The rectifier is an element which is in charge of taking the maximum power from the wind turbine in each moment by means of an optimum power tracking algorithm (MPPT for wind turbine). To achieve this goal, the control system is divided in two main control loops:
The first control loop deals with the speed of the machine. This speed control loop stablishes the reference of active power on each instant. Taking more or less active power from the generator, the control system is able to act over the rotating speed of the machine, accelerating or decelerating it. If in one moment it is necessary to decelerate the system, the control will require more active power from the generator, while the control will accelerate the machine if it demands less active power than in a previous moment.
The second control loop acts over the voltage at the terminals of the Permanent Magnet Synchronous Generator (PMSG). This control is able to manage the voltage of the machine through the control of the reactive power flow exchanged between the generator and the power converter. With this strategy is possible to maintain the optimum working point of the generator, reaching the maximum efficiency.
Figure 51 General Control Diagram
Depending on the wind resource in each moment, and taking into account the maximum power point tracking algorithm, the generator-side control system stablishes the current taken from the electrical machine (both active and reactive), the speed of the machine and the voltage at its terminals. The control strategy to be developed will fix the performance conditions of the wind generator on each instant.
VSC Controlled Inverter
The other power electronic converter acts as a power inverter, taking power from the DC bus to the AC grid. This inverter is in charge of controlling the connection of that DC bus (and so the wind turbine) to the grid. It synchronizes the performance of the wind turbine with the external low voltage grid. For this goal, two types of control loops are also implemented in the system:
The first one is able to keep the value of the DC voltage constant. Keeping constant the DC voltage value, it ensures that the active power flows from the PMSG to the grid through the power inverter. So, the inverter extracts, from the DC bus to the external grid, the optimum active power that the VSC Controlled Rectifier has taken from the PMSG. The second control loop acts over the reactive power exchanged between the power inverter and the grid. In the steady state, it is possible to work with reactive power equal to zero, i.e. power factor equal to one or even it may be able to participate in node voltage regulation providing or absorbing reactive power. Moreover, in transient state through these control loops, it is also possible to accomplish with different grid codes, dealing with the active and reactive current injected to the grid during disturbances as voltage sags.
The control theory applied for controlling both converters is the dq-vector control. These algorithms are being developed and simulated in the power system shown in Figure 51 using PSCAD. Once the performance of these algorithms is checked, they can be already implemented into a microcontroller, as a part of the task 5.4 Converters and PCB assembling and testing.
2.2.6. WP6. Structure integration in buildings/districts
Work package no. WP 6 Plan.Start: M03 Plan.End: M44
Lead Participant SAL Actual.Start: M03 Actual.End: M44
Work package title Structure integration in buildings/districts
Activity Type Research activities
Participant involved PPL SAL ULEEDS BAPE SOLUTE
Person Month (Actual Period)
0.00 3.75 0.00 1.88 7.00
Person Moth (Actual Project)
2.00 3.42 0.21 1.33 5.42
Person Month (Total project)
5.00 12.00 4.00 4.00 12.00
Actual Period Actual Project Total Project
Total Resources allocated 12.63 12.38 37.00
2.2.6.1. Task 6.1 Architecture and structural analysis of the typical urban constructions in Europe and the pilots
The purpose of this tasks is to study the three pilot sites/buildings and more broadly a typical sample of European urban and peri urban buildings compatible with small wind turbines from both a structural and aesthetic point of view. The task outcomes in 2 deliverables “D6.1 Structure Analysis Of The Masts” and “D.6.5 Structural Analysis Of Pilot And Other (Typical) Buildings”. Both deliverables are due in Month 24. As task leader, SAL decided in accordance with the task participants to manage the work best by splitting the task into 3 streams, 2 for D6.5 and 1 for D6.1 and to set progressive early internal deadlines for these.
SAL started with the research part of the WP and has in fact almost finished the draft atlas of typical European buildings from which structural analysis for the (other) buildings (in the task title) will be derived. SOLUTE has focused on the selected pilot buildings and along with BAPE and CIRCE have derived baseline (and detailed in some cases) architectural and structural design and calculation of the receiving buildings. The idea of both these processes is to understand and characterize the boundary conditions and thus limitations, and to allow (also under other tasks in this WP) generation of structural solutions that combines flexibility (for the typical buildings) with pragmatism (for the pilot buildings) and ensure the solutions are aesthetically optimised and with suitable restrictions and boundary conditions.
They will carry out a detailed analysis of its architectonic and structural characteristics in order to classify the different possible ways to
integrate the WT in them from both the structural and aesthetic points of view. Additionally SAL will exploit the results of the previous tasks in order to
Figure 52-Extract from Atlas of Typical European Buildings Suitable for SWTs
match the characteristics of the analysed anchorages and masts with the features of the existing buildings and thus, avoid compatibility problems caused by conflict of natural frequency, among others.
The atlas of most common typical building architectures and urban structures (and infrastructures) potentially capable of carrying WTs has been generated by Solearth based to some extent on precursor documents but relying to a large extent on research from first principles research. It is now 90% complete. The study took 5 typical cities in Europe and selected real buildings that represented repeating typologies common in sub and peri urban zones around Europe. These cities are Zaragoza, Hamburg, Goteborg, Bratislava and Geneva.
2.2.6.2. Task 6.2 Mast’s anchorages for typical urban construction and the three pilots
This task aims to develop the definition of the most appropriate anchorages for each building or location to the two WT that will not be fitted into the soil. Tasks under development so far are:
Collection of information related to the sites, specifically buildings. The data contained basically: constructive features, estimation of bearing capacity, geometric data. Study and analysis of data collected. Outline of preliminary and basic topological solutions of the anchorages. A few number of solutions have been proposed for each wind turbine anchorages due to the location and the machine are intrinsically different. Structural analysis of the solutions gathered; iteration on its features up to a satisfactory solution from structural point of view exclusively. Vibration transmission analysis of solutions. Final selection of better solutions after coupling two former criteria.
Previous to the abovementioned tasks, a study of the nature of the transmissions of vibrations that are originated in the rotor and will end in the building was carried out in a theoretical manner, so that general rules obtained could guide in the seek of the best solution among the possibilities gathered.
Among the most significant advances achieved within this task in this first project period, the next results can be highlighted:
Data of sites and buildings so far considered. Preliminary structural analysis of buildings: areas of WT location at roof. First estimations, evaluation and conclusions. Mathematical model of vibration transmission through building to be used in the evaluation of different solutions on each WT connected to a building.
2.2.6.3. Task 6.3 Structure of the masts at Pilot Buildings
This task aims to analyse the best suitable mast type for each kind of demonstration site taking into account the singularities of the locations in which they are going to be integrated. Also, the masts for the three pilots will be delivered under this task.
Tasks under developments are:
Loads collection at top tower as a starting point to dimensioning parts of the tower.
Template for the strength calculation of cylindrical tower that takes into account the predominant failures mode Market pre-study of standard parts that may suit dimensions result of strength analysis iterative process. Constructive solution for vertical axis WT.
Among the most significant advances achieved within this task in this first project period, the next results can be highlighted:
First estimations of dimensions and mechanical values of bigger WT. A whole geometric solution of vertical axis WT, fitted to different lengths, and even in a modular setting for different power or space at roof available.
2.2.7.1. Task 7.1 Noise and vibration sources assessment
The procedure for noise emission assessment from wind turbines are specified in the standard IEC61400.11 is now suited for today’s large turbines. Therefore, the BWEA (2008) standard including acoustic specifications of wind turbines is the recommended practice for small. and medium size turbines. The noise part of the BWEA standard has been investigated and found suitable to implement to the developed turbines in the SWIP project.
The BWEA standard is tailored towards using existing wind turbines to assess the total emitted sound power according to the standard procedure which is very similar to the IEC61400.11 standard but with adjustments of the wind speed at rotor height instead of 10 m has to be used and that the wind speeds have to be measured rather than derived from the power curve as is common for large turbines.
Naturally, measurements of the sound power emission cannot be performed on the turbines before they are built and operational. As this will be quite late in the SWIP project Task 7.2 is working on computing sound generation from the turbines and Task 7.3 is working on computing sound propagation in order to have a priori knowledge of the turbines noise characteristics at their specific locations before actually built and also to understand how perception of turbine noise in urban settings might change compared to today’s guidelines based on knowledge from rural wind turbine sites.
Consequently there was a need to investigate if the BWEA noise assessment of modern small and medium sized turbines is adequate for the SWIP project and if so implement these standards. As the standard seems to be sufficient to use implementation of the acoustical parameters are awaiting the erection of the turbines. According to the BWEA standard a noise map of turbines needs to be presented. This noise map is
based on emission measurements from the turbine but as these is not available at present moment as the turbines are not built. However, simulations of the noise emission by TCD and propagation from KTH are presented in Figure 53. As can be seen the T2 turbine is not exceeding 45 dB (where disturbances could be expected) at distances above 40 m for wind speeds at 8 m/s.
Figure 53 Noise map of the SWIP T2 turbine according to the BWEA procedure.
2.2.7.2. Task 7.2 Methodology for acoustic modelling and mitigation techniques
TCD has carried out noise source modelling for the three wind turbine designs. Two different approaches have been used for VAWT (V2) and HAWT (H6 and H30) designs. The general approach is to solve for the flow solution of the turbine and then to use semi empirical methods to calculate noise based on turbulence parameters of the flow around the blades.
The HAWT noise source modelling is performed using a code based on Boundary Element Methods to solve the flow solution of the rotating blades followed by noise modelling based on the flow solution. Corrections are also applied for post-stall airfoil behaviour and tip losses. Inflow noise and Turbulent Boundary Layer Trailing Edge (TBL.TE) noise are modelled using two semi empirical approaches [3,4]. This model was verified and validated by using that code to solve for the noise of various existing turbine designs as well as a more empirical Wolf model [1].
The VAWT flow solution is solved with CFD by using 2D unsteady RANS simulations. This data is extrapolated onto a 3D grid from which the same semi empirical relations as for the VAWT approach are used to solve for the noise sources. The VAWT noise models still need to be verified against existing designs but data is scarce. A conference paper has been published to showcase this novel approach [2].
Recommendations were provided during the SWIP GA in Nantes with regards to H6 and H30 designs for noise mitigation. As a result of discussions with the blades aerodynamics groups and atmospheric modelling who had proposing downsizing to H4 and H20 configurations, the noise for the new horizontal configurations were shown to be less than the numbers quoted below. Efforts were then focused on development of methods to analyze the vertical configuration.
Next, the most significant results can be seen:
The table below gives a summary of the noise predictions for the three SWIP wind turbine designs. These noise predictions are all for a receiver at 2x hub height downwind. The predictions are compared to empirical models to show their validity.
Table 8 Noise predictions for the three SWI wind turbines
Turbine Prediction (dB) Wolf Model (dB)
H6** 43.7 44.9
H30** 49.7 51.8
V2 45.8 44.5*
*flat plate empirical model used **H4 and H20 confirmed to be quieter.
Figure 54 Turbulent Kinetic Energy of V2 turbine and accompanying noise results:
Figure 55 SPL H6 and H30 respectively with change in RPM
[1] W.B. de Wolf. Aerodynamisch geluid van windturbines (in dutch). Technical report, NLR.MP87004U, January1987.
[2] JDM Botha and H Rice. A novel method of vertical axis wind turbine noise prediction. Euronoise, 2015.
[3] M.V.Lowson. Assessment and prediction of wind turbine noise, flow solutions report 92/19. Technical report, ETSU W/13/00284/REP Bristol, England.AIAA.2002.2521, 1993.
[4] T.F.Brooks D.S.Pope M.A.Marcolini. Airfoil self.noise and prediction, reference publication 1218. Technical report, National Aeronautics and Space Administration, USA., 1989.
2.2.7.3. Task 7.3 Noise and vibration solutions implementation
Apart from the sound source model the assessment of sound propagation needs to be addressed in order to calculate the noise dose at receiving positions. This propagation issue is particularly emphasized in urban and peri-urban areas where buildings will act as noise barriers or reflectors and thus the acoustic propagation can have a large impact on the sound levels at listening positions. Implementation of a Boundary Element Method (BEM) has also been developed, see Figure 56 for an example of this calculation method using a single building. The calculation method is 3D and includes the physically relevant phenomena of sound propagation in urban areas; backscattering, refraction and diffraction. The BEM method is considered faster than solving FEM based equations as the computational domain is restricted to the building surfaces rather than the entire 3D computational domain necessary for FEM algorithms. Moreover, coding of a ray tracing algorithm has been initiated although not yet completed and validated against benchmark cases or the BEM code. At the present moment the precise locations of the turbines remains to be decided but site configurations for the three demo sites have been acquired from Meteodyn and estimations of sound propagation at the sites can be started with the BEM code once turbine locations are chosen.
The human perception of wind turbine noise is naturally also central for the acoustic part of the project and how well wind turbines can be integrated in urban settings. As the noise impacted population today dominantly lives in the countryside no specific knowledge exists if the sound characteristics of small and medium sized turbines differ from larger turbines or how masking in urban soundscapes are perceived. In order to evaluate the impact of the noise on nearby residents two questions needs to be addressed (i) the sound quality of wind turbines and (ii) that the overall sound environment has to be taken into account. For instance, the audibility of a sound is far less adjacent a busy road than in quiet locations like a backyard or in the countryside. Several recordings of wind turbine noise from mainly small and medium size turbines have now been performed in the project by the use of a binaural head, see Figure 57. This measurement technique is suitable when playing sounds in headphones and has been refined by adding Rycote wind protections to the head and therefore decreasing the amount of wind disturbances in the recordings especially important in listening tests as wind disturbances in recordings are attention grabbing and disrupting the listening experience. Masking effects and sound quality aspects of small and medium sized turbines are presently being investigated by KTH in order to study if today’s guidelines for wind turbine noise are suitable in built-up areas. These tests are performed by using state-of-art scaling methodologies by continuously judging the sound and providing instantaneous feedback to the listener and thus giving larger amount of data to analyse than traditional psychophysical methods.
Figure 57 Binaural head recording technique
In total the fulfilment of the objectives of Task 7.3 are progressing according to the project plan.
The aim of this task is a study of existing safety standards and related literature with respect to small wind turbines (SWTs). The focus is on placement of SWTs in urban area. Issues such as icing and other potential hazards of placing turbines in populated areas are analysed and recommendations on how to address these issues are proposed.
There exist two standards specifically about SWTs: IEC 61400.2 and RenewableUK. The latter is only a summation of reference to the IEC 61400.2 and to normative references in this IEC standard. The IEC standard provides several guidelines and requirements regarding safety of SWTs from hazards during their planned lifetime. However, this standard appears to have shortcomings on determination of wind conditions and risks and inconvenience for local residents such as icing, vibration, noise and flickering. The standard IEC 61400.1 (wind turbines – design requirements) provides a good completion on determination of wind conditions. The standard IEC 61400.11 should be referred to on the topic of noise, it gives precise requirements on measurements.
The problem of icing is insufficiently described in the studied standards. Therefore, several reports and articles on this topic are studied. Current knowledge of safety aspects when considering icing is restricted to horizontal axis turbines at rural sites. There are recommendations of safety distances as rule-of-thumbs for ice throw and ice fall for such constructions. The distance is independent of azimuth angle while the distribution of debris is higher downwind of the turbine. As the direction of rotation is not perpendicular to the wind direction for some turbine configurations, assuming safe areas in front of turbines is not recommended.
Appropriate requirements for electrical components are found in IEC 61400.2, IEC 60204.1, IEC 60364.5.54, IEC 62305.3, IEC 61400.24 and IEC 60034.5. IEC 60204.1 covers requirements to guarantee the equipment electrical safety and required tests of the equipment. In the standard IEC 60364.5.54 contains requirements on earthing. Requirements on protection against lightning are covered in IEC IEC 62305.3 and 61400.24.
Several recommendations are provided following from the studies. There should be compliance with standard IEC 61400.2 and its normative references. For the safety of persons it is recommended that people in the area of SWTs do not approach an active SWT within a radius of 3 m, unless they are authorized personnel. Noise measurements should be carried out according to standard IEC 61400.11. For noise levels the recommendation is a maximum of 37 dB at 6 m/s wind speed and 39 dB at 8 m/s wind speed. SWTs should be placed on a structure which prevents vibrations from passing from SWT to building and flickering should not be visible to people in surrounding buildings. Regarding icing it is recommended that there is compliance with the formulas mentioned in chapter 2, or that measures are taken to
again when the SWT is free of ice. Electrical components should comply with IEC 60204.1, IEC 60364.5.54, IEC 62305.3 and IEC 61400.24. Site-specific wind conditions should thoroughly be examined.
2.2.7.5. Task 7.5 EMI requirements compliance
The ability of the equipment to work satisfactorily in its electromagnetic environment is called electromagnetic compatibility (EMC). The EMC means to be immune to the electromagnetic disturbances produced by other equipment (electromagnetic susceptibility . EMS) and not to introduce intolerable
electromagnetic disturbances to other equipment (electromagnetic interferences . EMI). These both main requirements shall be assured by the equipment manufacturer.
With the aim of ensuring that devices developed in this project are according to regulation, several normative, like IEC standards and CE directives, are researched. As result of this researching, mandatory regulations concerning EMC for small wind turbines, electrical rotating machines and power converters are determined (Figure 58).
Figure 58. Diagram with EMC regulations.
Once these regulations are collected, the specific standards are analyzed with the aim of stablishing EMC requirements. Furthermore, the necessary tests for ensuring the accordance of proper equipment immunity level and for measuring the interferences caused by the equipment are analyzed. These test procedures and the main equipment needed to perform them are summarized in task 7.5.
Finally, several electromagnetic mitigation methods are researched in order to gather different solutions, which may be applied as corrective measures when the EMC requirements are not met by the equipment. In particular, task 7.5 deals with shielding (Figure 5959), filters (Figure 6060 and Figure 6161), decoupling devices and surge-protective devices (62).
Figure 59. Shielding examples a) emmision; b) immunity.
The electromagnetic compatibility of the apparatus shall be assured by manufacturers. In order to assure the electromagnetic compatibility of the apparatus, the equipment shall be tested. The test procedures and the requirements which shall be met in these tests are regulated by several standards. In case the test results do not meet the requirements, several corrective measures may be adopted. The mandatory regulations, EMC requirements, test procedures and electromagnetic mitigation methods are gathered in the task 7.5 document.
Participant involved SAL ULEEDS DARMS BAPE SOLUTE TCD
Person Month (Actual Period)
1.00 0.00 0.00 4.24 0.00 0.00
Person Moth (Actual Project)
1.20 0.00 0.00 2.40 0.00 0.00
Person Month (Total project)
5.00 1.00 1.00 160 3.00 1.00
Actual Period Actual Project Total Project
Total Resources allocated 5.34 3.90 50.50
2.2.8.1. Task 8.1 Development of a deployment plan for each pilot
This task deals with the development of the deployment plans for 3 demo sites. The aim is to set and align all elements and stakeholders that will be involved during the testing phase. The final composition of and elements to install in each pilot will be defined here. The deployment plan aims to co-ordinate the activities, entities and people involved in the deployments and installation of the WTS, to assure the correct deployment and of the equipment, avoiding/mitigating risks at this stage. The monitoring plan will be delivered also in each deployment plan. There will be workshop arranged for demo sites, to discuss and define a common methodology for measurements and evaluation performance.
Since early stages of the project, all steps necessary to develop SWT projects in urban and peri-urban areas has been examined and started developing the deployment plan. Experiences have shown that all administrative procedures are very time consuming and this aspect has to be strongly taken into consideration when planning SWTs construction. In both Polish locations (Choczewo and Kokoszki), it was necessary to obtain written agreements to install met masts and WTs. The agreements cover different aspects like exact locations of the installations, time frames, payments for renting the ground, scope of the responsibilities, insurance etc. Usually it requires participation of different staff members on the ground/building owner side to take such decisions. Therefore, if a developer (investor) is not the property owner, this process has to be also taken into account in the deployment plan. After reaching the agreement one has to start working on technical documentation and design of the met mast construction, and later proceed to the installation. The most time consuming phases are acquiring permissions for construction of met masts and WTs. In Poland – for Kokoszki site . it took 5 months to receive a building permission for the met mast. It has to be mentioned that the potential developer is not in the position to speed up the process
as numerous approvals with different institutions and companies have to be acquired and sometimes it is necessary to make adjustments required in the process. One of the last steps of the process is getting an agreement from a dedicated committee at the province level administration on issuing the building permit. Finally, it takes 14 days before the building permit enters into force. Only then, one can start construction works under supervision of an authorized building site manager. After construction works are completed it is also necessary to get a permission to use the installation. It is worth mentioning that in both Polish cases (Choczewo and Kokoszki) construction of met masts including installation of meteo equipment took one day each.
At the same time all other stages necessary for implementation of the pilot projects have been identified. They have to be considered during planning phase and they include: scope of the wind measurements, construction of WTs components (generator, blades, SCADA, converters, mast/frame, anchorages), laboratory testing (generator, blades, SCADA, converters), construction of WTs (building design, building permit, grid connection), transport of elements to the pilot sites, assembly and construction of WTs, safety tests, monitoring and metering, WTs certification. Stakeholders, risks, mitigation measures are under development. A template table has been developed by BAPE and discussed with respective partners. Based on the data presented by BAPE respective partners are adjusting all necessary information for further development of the deployment plan.
The deployment plan should be as realistic as possible. It is very important for potential investors to estimate time frames (incl. different stages), to present risks, possible difficulties and mitigation measures that may appear during the project implementation. The deployment plan shall serve as a tool which might be used by local municipalities when planning SWT installations.
Participant involved SAL ULEEDS DARMS BAPE SOLUTE TCD
Person Month (Actual Period)
0.00 0.07 0.00 1.00 0.50 0.00
Person Moth (Actual Project)
0.34 0.35 0.34 0.77 0.34 0.35
Person Month (Total project)
0.50 0.50 0.50 2.50 0.50 0.50
Actual Period Actual Project Total Project
Total Resources allocated 16.03 23.25 37.00
2.2.9.1. Task 9.1 Development of a dissemination and awareness plan
Greenovate! Europe has completed and submitted Deliverable 9.1, the Dissemination and Awareness Plan, in Month 6 of the project. The Dissemination and Awareness Plan sets out how the SWIP project can ensure that all project results and opportunities are communicated to relevant stakeholders, in a consistent manner. Dissemination and Awareness activities should contribute to the long-term impact of the SWIP project results, by highlighting key messages and making clear the opportunities and advantages of the results. Such activities support exploitation and long-term market impact.
The Dissemination Plan outlines who (target audience) will receive what (key messages), how (communication channels) and when (planner). It also outlines the role of the consortium partners to ensure proper exploitation of generated knowledge. All partners were asked, via questionnaire, to contribute to the Plan by outlining their expected activities, including presentations at events, and publications.
The Plan proceeds by presenting information on the target audiences of the project, as well as the identified routes for reaching these audiences. After this, the procedure for approval of activates is outlined. All partners must seek approval of activities before they are implemented. Two procedures apply – one for dissemination activities and a less stringent procedure for awareness raising.
A second Deliverable related to this task, Deliverable 9.3, is due in Month 20 of the project. This Deliverable will present a summary of the Dissemination activities performed by the SWIP partners throughout the course of the project. This information has been collected from partners, with partners submitting information on activities to Greenovate! Europe, as and when ready, following the protocol set out in the
Dissemination plan. In order to ensure that no information was missing, a questionnaire was sent out in Month 18. All information regarding Dissemination has been uploaded to the Participant’s Portal.
There is no deviation in this Task from Annex I, and no problems are expected in submitting Deliverables 9.3 and 9.4 (Final Report on Dissemination Activities – M44) on time.
2.2.9.2. Task 9.2 Promotional material
The aim of this task is to disseminate the project as well as their results itself to achieve the highest possible project impact and visibility. To do so, this task deals with the creation of the website and promotional material.
So far, the website has been created. Different sections have been created in order to organize the information that is presented to the users, this information is differentiated by general information of the project, partners description, demo sites description, publications, news and links. Additionally the website has a direct link to the intranet of the project.
Figure 63 SWIP website Homepage
Several publications have been performed in order to disseminate the project through different channels.
In addition, a leaflet with the main features of the project has been created.
Task 9.3 is one of the dissemination activities within the SWIP project. Various events will be arranged in chosen demo-locations to present achieved results. At this moment the project is at too early stage in to present real effects of the SWTs installation.
At this stage of the SWIP project, a seminar was arranged in Choczewo, SWIP project was broadly presented and information on wind measurements were given. Afterwards an article for the local press was written and issued in electronic version on the official website of the commune. The event took place on May 30th, 2014.
Figure 65 Seminar in Choczewo (30.05.2014)
2.2.9.4. Task 9.4 Dissemination to the targeted audience
Historically, one of the most significant barriers to market adoption of renewable or alternative energy is the lack of a good business case for implementation. In recent years there is an increased awareness on the importance of the renewable small-scale energy sources in urban and peri-urban areas, where the exploitation potent benefits for society are seen as the most promising ones. The objective of this task is to conduct a research on business case opportunities for small wind turbines in urban and peri-urban areas. More specifically, this part of WP9 aims at analyzing aspects that promote the deployment and dissemination of small wind turbines by developing suitable business models and to inform the local stakeholders and the wind industry. The (local) workshops and presentations at the wind industry events
will take place in the second part of this project. The local workshops will be held just before the installation of the SWTs to inform the local audience and to get feedback about the plans.
A start with the literature research is made on the existing technology and market in order to get a clear view of the technology development that has taken place so far. Business models are formed to unite participants from multiple industries to guide service design and delivery in SWTs. Further, a questionnaire is formed to investigate the willingness of property owners to invest in the technology, as they are considered to be the driving force for the dissemination of the technology. Moreover, certification’s role is deeply studied in order to specify its influence on the technology. The most important barriers will be identified and will be communicated to the targeted audience. After feedback from the targeted audience solutions are proposed to minimize the barriers.
2.2.9.5. Task 9.5 Detailed market and competition analysis
During this first period, the Market Analysis has been completed by G!E third party, CEIS Innovation 128, which allows SWIP partners to get a complete overview of the SWT market at the European and international levels. For each of the main markets (US, UK, Italy, Germany, France and Spain), several items have been explored in order to better understand the present market and the perspective up to 2020.
Firstly, stakeholders, including the main international small wind manufacturers, were mapped, then, costs and return of investment of SWT products and technologies were reported. Finally, standards, certifications and incentives were also explored. The main markets were compared at an international level to underline leader and challenger markets, as well as barriers and challenges that need to be considered for growth of the SWT market. Moreover international case studies were presented in order to highlight stakeholder’s interactions, potential customers and innovative business models.
To build this report open data was analysed and a market survey was completed, with fifteen interviews performed from over fifty people who were contacted. All details on the interviews can be found in the Deliverable.
The study revealed that to overcome the main barriers, there are several points that need to be worked on. First, there is the need for a strong support from public and local authorities, who can give a fair feed-in-tariff and support investment and demonstration projects. They will also have a key role to play in forming an efficient regulatory system for installation. Interviews supported the idea that a major weakness in current marketplace is the lack of wind resource assessment tools, to overcome the challenges of installing SWTs in built-up areas.
Recommendations arising from the analysis include the creation of a quality label to enhance customer confidence and further building of social acceptance, which is generally low, and secondary to awareness of competing solutions such as Solar PV. It is also recommended that engineering companies should perform all necessary impact and performance studies, to ensure that customers have good recommendations on what SWT to purchase, and where to install it. The best approach may be an all.in.one provider, who can manage all aspects of installation, including financing, permitting, installation and maintenance, as part of an SWT leasing package, keeping costs down for the consumer, whilst boosting confidence in performance.
In order to make the results of the survey clearer for the SWIP consortium, CEIS has given presentations at two of the project meetings, in Sheffield in April 2014 and then in Nantes in October 2014. The full
Deliverable 9.5 – Market Analysis for Small and Medium Size Wind Turbines was submitted in September 2014.
2.2.9.6. Task 9.6 Business and exploitation plan
Task 9.6.1 – Definition of exploitable results
During the kick off meeting, a short introduction about exploitation was given by the exploitation leader, Van der Meer en Van Tilburg (G!E third party). This was then built upon during the M6 consortium meeting, which also contained the first exploitation seminar, with the aim of identifying the main exploitable results with the rest of the consortium partners. The following outputs were therefore identified as key results:
1. The three newly developed SWTs – Two Horizontal Axis (small and medium sized) and one Vertical Axis,
2. The integrated solution for wind harvesting in a district or a building (wind and impact assessment, technology provision, installation) and;
3. The newly developed methodology and software for wind resource analysis in urban and peri-urban areas.
In addition to these results, the different components that are being developed could also be exploited separately.
During the second exploitation seminar, the consortium partners have made a forecast for the Technology Readiness Levels (TRLs) that they think could be achieved at the end of the project. Most participants expect to reach TRL 7 (System prototype demonstrated), although the new methodology for wind resource assessment was estimated to reach TRL 3 (Experimental proof of concept).
Task 9.6.2 – Development of exploitation strategy
In the first exploitation seminar a presentation of the general exploitation strategy was given and discussed, including the different routes to market. Aspects such as (joint) ownership of foreground, freedom to operate and access to background were discussed.
A key issue for being commercially successful with the technology which is being developed is that it can be exploited via different business models. This was a major part of the discussion during the first exploitation workshop, with the aim of informing discussion about suitable business models for the exploitable results.
In the M12 consortium meeting, a second exploitation seminar was also held, which included a discussion about the results of the market study, specifically in light of future exploitation of the project results.
In order to gain a better understanding of the SWT market, a series of interviews have been held with stakeholders in the Netherlands, particularly current users of first generation SWTs. Since the first deployment of these wind turbines, several developments and improvements have been made. The main conclusions for the first generation SWTs is that the generally did not deliver the promised energy performance, and have not lived up to promised technical robustness.
It appears that the main reasons for most users to deploy one or more SWT’s have been to try to reduce energy costs, but also to cultivate a sustainable appearance of the company for customers. At this moment, it appears that companies maintain the deployed SWTs on their properties mainly for green washing reasons, as they still achieve their second aim of building a sustainable appearance. A SWT on the roof has a higher green image than a set of solar panels. The SWT’s that will be developed in SWIP will have to prove that they are better, and any sort of negative image of under-performance will have to be overcome.
Task 9.6.3 – Development of business models and plans
In parallel, the content overview of a preliminary business plan for the exploitable results has been developed. All three turbines share characteristic features, like wind resources, yield, mounting, etc. In addition, general statements on a marketing plan, management, IP and financial issues apply to all exploitable results.
In preparation for developing business plans, financial calculations have been made for the deployment of SWTs in an off-grid application in temporary constructions (e.g. a construction site), with calculations having been made for a small and a large temporary structure. These models have been explored for providing electricity, with and without serving an energy need for heating. These financial calculations for off-grid application and analysis of the market study (D9.5) give input for the further development of the business plans.
There are no significant deviations from Annex I, and Deliverable 9.6 ‘SWIP Business and Exploitation plans’, is expected in Month 44.
2.2.9.7. Deviations from Annex I:
According to the Gantt Chart of the project, task 9.2 ends on month 4 of the project, but according to the description of the task, most of the material to be produced will be used for the dissemination of the results which will come at the latest stages of the project. Due to this, we are proposing to enlarge this task to the end of the project (this proposal will be presented within the next amendment).
This issue do not affect to any other task of the project nor their regular functioning.
2.3.1. Consortium management tasks and achievements
The tasks and achievements concerning SWIP project management activities are listed below:
Supervision of project progress and assuring the effective realization of the E+ implementation plan
Contact point with the EC and third parties
Reception and distribution amongst partners of EC contribution
Definition of project communication flows and tools
Periodic update of the Implementation and financial plans
Maintenance of the Consortium Agreement
Responsible for the collection of partner progress and financial reports and preparation of related reports to the EC
Submission of other deliverables to the EC
Proposition of a Quality Assurance Plan and oversee the appraisal of financial, legal, administrative and technological risks and related contingency plans
Contact with other European/national initiatives
Oversees the awareness, dissemination and training plans and their deployment
Oversees the exploitation plan and management of knowledge & IPR
The following figure illustrates the homepage of the project intranet, main tool used for the project management and coordination:
Figure 66 SWIP project Intranet Homepage
2.3.2. Problems which have occurred and how they were solved or envisaged solutions
A new task was identified as needed for the completion of the WTs but was not included in the DOW. By means of a reallocation of budget between POLIPLASTAS and SOLUTE, we covered this need without requiring any extra effort. This action was formalized through an amendment.
Change of Demo site from Borkowo to Kokoszki. During the kick –off meeting, BAPE presented an alternative pilot site that also could be considered if needed. After a technical analysis of the representativeness of both (Borkowo and Kokoszki) pilot sites, it was identified that Kokoszki pilot site present better characteristics to be the industrial demo-site. This decision was formalized through an amendment.
Met mast installation delay. The installation of the met masts in the different pilot sites was delayed due to the need to agree of a common composition of the met mast according to the parameters
needed in subsequent stages of the project. Being confident on the no affection of this delay in other related tasks, the measurement period was enlarged from M12 to M24.
Change of Demos site in Zaragoza. The WT in Zaragoza would be installed in a building that is going to be built within the NEED4B project. The delay on the construction of this building affected to the installation of the WT since the building is not going to be built when the WT has to be installed. In order to solve this situation, it has changed the location of the Zaragoza pilot site to a place in which the installation of the WT is not dependent of external factors and where the previous work of the project can be also useful for this new location which will be the current CIRCE´s building. This change of the demo site is going to be formalized within the next amendment.
2.3.3. Changes in the consortium, if any
Change of partner. At the end of February all team in charge of the SWIP project for the University of Leeds has moved to the University of Sheffiled. The University of Leeds has left the project and in its replacement, the University of Sheffiled has entered in the project. With this change of partner, the common risks associated to the change of partners that could arise at this stage of the project are not present since the same work team in charge of the SWIP project in the University of Leeds is in charge of the SWIP project in the University of Sheffiled. This change of the demo site is going to be formalized within the next amendment.
This annex collects the blade design reports for the three different types of blades that will be manufactured for the SWIP prototypes. At the beginning of the project, it was decided that the power for the prototypes for Kokoszki and Zaragoza would be 30kW and 6kW respectively. After some iterations and wind resource and site analysis, it was decided among project partner to reduce the power of both prototypes to 20kW and 4kW. Blade designs had already been performed, so it was decided to adapt the designs already performed for H30 and H6 to the new power of the prototypes. The following reports are collected:
SWIP. H6 WI ND TURBINE SWIP. H4 WIND TURBINE (Update of H6 report) SWIP. H30 WIND TURBINE SWIP. H20 WIND TURBINE (Update of H30 report) SWIP. V2 WIND TURBINE
Draft date: 22.12.2014 10:33 Page 94 of 94
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28703 San Sebastián de los Reyes
Madrid, Spain
T +34 91 658 82 04
F +34 91652 51 81
www.solute.es
Avenida Cerro del Águila, 3 edificio 2, oficinas 1C2, 1D2
3.2 Twist law ........................................................................................................................ 9
3.3 Angle of attack ............................................................................................................ 10
3.4 Chord law .................................................................................................................... 10
3.5 Reynolds number ........................................................................................................ 11
4 Test Results ......................................................................................................................... 14
5 Election of the final model .................................................................................................. 24
6 Exchange of information ..................................................................................................... 29
FIGURES INDEX
Figure 1. Interface Qblade ............................................................................................................. 3 Figure 2. Airfoil design ................................................................................................................... 4 Figure 3. Polar extrapolation to 360° ............................................................................................ 5 Figure 4. HAWT Rotorblade Design ............................................................................................... 5 Figure 5. Rotor BEM simulation .................................................................................................... 6 Figure 6. Some airfoils used .......................................................................................................... 8 Figure 7. Triangle of speed ............................................................................................................ 9 Figure 8. Lift curve ....................................................................................................................... 10 Figure 9. Values SP acording to the SR ........................................................................................ 11 Figure 10. Angle of attack of the NACA 63-415 airfoil ................................................................ 13 Figure 11. First tip model (a) and second tip model (b) .............................................................. 14 Figure 12. Two different blade tips ............................................................................................. 24 Figure 13. Power curve................................................................................................................ 31
1 WIND TURBINE DESCRIPTION Within the SWIP project, this report describes the process of aerodynamic study has been
carried out to design the horizontal axis wind turbine and rated at 6 kW (H6). It will be placed on the roof of a building in Zaragoza.
The design and operating conditions are:
Three-bladed wind turbine Rated Power 6 kW. Average speed on the site 4m/s. Design Wind speed (v) 8 m/s. Blade length (R) 4 meters. Rotational speed (ω) 80 rpm
The condition of a low tip speed ratio (λ) is imposed to reduce wind noise, hence it is convenient to define a greater solidity of the chord.
A project partner would be responsible of the noise study after having passed the necessary data.
2 SOFTWARE DESCRIPTION. The program used for the studies of power curve is QBlade [1], an open-source software
distributed under GPL license. It integrates XFOIL, a tool for design and analysis of airfoils with which you can simulate a wind tunnel to obtain the lift and drag coefficients (Cl, Cd).
Figure 1. Interface Qblade
The procedure required to obtain the generated power is as follows:
- Airfoil design - XFOIL Direct Anlysis - Polar extrapolation to 360° - HAWT Rotorblade Design - Rotor BEM Simulation - Turbine BEM Simulation
[1]F. Bertagnolio, N. S. Rensen, J. Johansen, Wind Turbine Airfoil Catalogue, RisØ-R-1280(EN), RisØ National Laboratory, Roskilde, Denmark, Agosto 2001
Airfoil design: Viewer Profiles. Ability to modify parameters (thickness, camber).
Figure 2. Airfoil design
XFOIL Direct Analysis: Analysis of coefficients (Cl, Cd) as Reynolds number will vary for each chord.
Polar extrapolation to 360°: Based on the graphs obtained in the previous section an extrapolation of the data of Cl and Cd for 360 ° angle of attack is created.
Rotor BEM Simulation: Preparation of Cp as a function of TSR using the BEM [2] theory. The aim is to get the greater Cp as the lowest TSR as possible to decrease the speed and noise caused.
Turbine BEM Simulation: Simulation of the power obtained. Range of wind speeds, rotation speed is defined and optimal TSR (maximum Cp obtained in the previous section) is obtained.
3 STUDY METHODOLOGY. The procedure carried out in this project is based on a series of tests for different suitable
airfoiles for this type of wind turbines and different desing configurations with which they seek to get the most power (nominal 6kW) at the lower wind speed possible as it is an urban location and the wind speeds will not be very high.
Necessary imput:Number of blades, Lambda(λ), Rotational speed (ω),Wind speed
(v), environmental conditions, wind turbine radius and chord.
The steps followed for the study of the different models are explained below, the calculations and results can be seen in paragraph 3 (test results) and Excel H6_chord_twist.
3.1 Aerodynamic Profiles
Among the many existing airfoils on the market have been selected are those commonly used in wind turbines based on the report Riso-R-1280 (EN), which were performed comparisons between different values of coefficients (Clift, Cdrag) with experimental measurements and code data calculation aerodynamic as EllipSys2D and XFOIL.. The QBlade program is based on XFOIL code. The selected airfoils have good performance for dirt accretion which is a good property while operating in an urban environment.
Airfoils have been chosen with a thickness between 12 and 15% at the tip and about 35% at the root since it must withstand the maximum moments of aerodynamic forces transmitted through the blade to the root.
Blades studies with these profiles have been carried out:
- Blade with airfoils DU 99W350, DU 97W300, DU91-W2-250, DU93-W-210, NACA-63-415 y NACA 63-418
- Blade with airfoils S808, S807 y NACA 63-415 - Blade with airfoils FFA-W3-301, FFA-W3-241, NACA 63-418 Y NACA 63-415.
is the angle of attack, r the radial position of the different sections of the blade, W the relative velocity, , ω the rotational speed (80 rpm) and v the wind speed (8m/s).
The Betz limit indicates that only about 60% of the energy contained in the wind is
convertible into useful energy at the turbine. This limit is the which is obtained for coefficient equal to 1/3 approximately.
This method of calculating the twist gives very high results on the root so the first values
were changed by assigning more logical values, because the more twist the blade has, the harder it is to make the mold.
An attack angle such that the lift coefficient in the pre-stall, next to the maximum lift coefficient is chosen hence it is convenient to define a greater consistency of the "chord".
Figure 8. Lift curve
Operating in the pre-stall zone, we have the advantage that when the wind speed increases, the lift coefficient remains in a range of acceptable values. Another implication is that operating in this zone, the solidity has reasonable values and the cost of fthe blade does not increase.
3.4 Chord law
Blade with different chord methods have been made.
Where the shape parameter (SP) that is, depending on the speed ratio (SR) of the following graph.
Where: i → Blades numbers.
R → Blade length and r the rotor radius.
λ → Tip speed ratio ;
→ Lift coefficient.
As with the twist, these methods give very high values at the root, so these were reduced to more logical values based on other models of blade used in this type of wind turbines, and with the option to add a trendline in Excel, an equation for the chord will be obtained.
3.5 Reynolds number
To calculate the Reynolds number has taken the following procedure.
- Calculate the chord (c) by taking the maximum chord for each airfoil. - Calculate the relative velocity W.
With these final Reynolds number, the angle of attack can be choosen by the following procedure:
- In the QBlade program, in the analysis section, the final Reynolds number is entered. - In the cl-alpha curve, the angle of attack is studied as it is explained in paragraph 3.3.
Example: for NACA 63-415 airfoil, whose Reynolds number is 796485, the angle of attack chosen is 10 °.
Figure 10. Angle of attack of the NACA 63-415 airfoil
4 TEST RESULTS Different blade models have been performed using NACA, DU, S and FFA airfoils and two
types of tips to produce pitching moment at blade root that will be used to move the pitch.
Figure 11. First tip model (a) and second tip model (b)
After the meeting with Poliplastas, project partner tasked with blades manufacturing, where it was reported that there are no problems with any of the two forms, it was decided that the shape of the blade tip would be the second since more is obtained with it.
As starting hypothesis zero thickness at the trailing edge is assumed. This parameter will be modified once the thickness of the shells and the manufacturing conditions are known.
Then the airfoils will be modified in QBlade and the polar and the power curve will be recalculated.
b. DU and NACA profiles with first chord method and second tip model :
As has been explained before, the root values are very high and these have been modified to more logical values based on other models of blade used in this type of wind turbine, and with the option to add a trendline in Excel, an equation for the chord will be obtained.
The final Reynolds number is calculated with this chord, then the alpha is chosen and the twist is calculated with the procedure explained in section 3.2.
As in the chord, the method to calculate the twist at the root gives very high scores (approximately 50-60ᴼ) so that the first 50 centimeters were modified, assigning lower values, because the more twist the blade has, the more difficult is to make the mold. Then, with the option to add a trendline in Excel, an equation for the twist will be obtained.
Once made the different tests, the blade with profiles DU_NACA was chosen for the following reasons:
− These are the most commonly used profiles. − As the turbine is destined to operate in urban environments, dirt and noise emission
should be considered. According to studies performed by the University of Delft [5], DU06-W-200 airfoil is suitable for this site for good behavior with the dirt and noise emission. The 63nnnNACA series are good for dirt too. [6]
− Result power coefficients ( ) of about 0,5 and powers provided are reached.
Among the various tests with these blade profiles, the blade with the best was chosen.
With the law of chord obtained in paragraph b of section 3 (test results), two different models were performed in which the difference is curved blade tip backwards.
It was decide to put a circular profile in the first 20 centimeters to improve the structural behavior.
The possibility of increasing the size of the spinner will be evaluated to reduce losses in the root zone.
[5] Rooij-roughness_sensitivity_AIAA2003-0350 [6] R.J. Margarita, Influencia del ángulo de ataque,2004
The results of this project should be sent to three project partners. - Kth (noise study) - Poliplastas (manufacturers) - Cirse (generator and box) - Brian O’ Brian (aesthetic)
The changes that have been carried out to transform the initial model are:
Final model Initial model
H4 H6
ρ (Kg/ ) 1.225 1.225
μ ( ) 1.83 1.83
rpm 120 80
Number of blades 3 3
Blade length 2.79 4
Radius 3 4.25
Power ( ) 4 6
The main reasons for the last changes have been the limits in the budget to build the generators and the permitted urban noise levels. The noise analysis has been carried out by Trinity College Dublin, and the limitations regarding the generator by CIRCE and FORES.
The aim is to increase as much as possible the rotational speed to get smaller generators without overcome the noise limits for urban environment.
3.2 Twist law ...................................................................................................................... 50
3.3 Angle of attack ............................................................................................................ 51
3.4 Chord law .................................................................................................................... 51
3.5 Reynolds number ........................................................................................................ 52
4 Test Results ......................................................................................................................... 55
5 Election of the final model .................................................................................................. 64
6 Exchange of information ..................................................................................................... 69
FIGURES INDEX
Figure 1. Interface qblade ........................................................................................................... 44 Figure 2. Airfoil design ................................................................................................................. 45 Figure 3. Polar extrapolation to 360° .......................................................................................... 46 Figure 4. HAWT Rotorblade Design ............................................................................................. 46 Figure 5. Rotor BEM Simulation .................................................................................................. 47 Figure 6. Some airfoils used ........................................................................................................ 49 Figure 7. Triangle of speed .......................................................................................................... 50 Figura 8. Lift curve ....................................................................................................................... 51 Figure 9. Values SP according to the SR ...................................................................................... 51 Figura 10. Angle of attack of the DU 93-W210 airfoil ................................................................. 54 Figure 11. First tip model (a) and second tip model (b) .............................................................. 55 Figure 12.Power curve ................................................................................................................ 71
9 WIND TURBINE DESCRIPTION Within the SWIP project, this report describes the process of aerodynamic study, carried
out to design the horizontal axis wind turbine and rated at 30 kW (H30). This will be placed in an industrial area in Kokozski, Poland.
The design and operating conditions are:
Three-bladed wind turbine Height to blade tip 30 meters. Rated Power 30 kW. Average speed on the site 3m/s. Design Wind speed (v) 8 m/s. Blade length (R) 7 meters. Rotational speed (ω) 70 rpm
The condition of a low tip speed ratio (λ) is imposed to reduce wind noise, hence it is convenient to define a greater solidity of the chord.
A project partner would be responsible of the noise study after having passed the necessary data.
10 SOFTWARE DESCRIPTION. The tool used for the studies of power curve is QBlade [7], an open-source software
distributed under GPL license. It integrates XFOIL, a tool for design and analysis of airfoils with which you can simulate a wind tunnel to obtain the lift and drag coefficients (Cl, Cd).
Figure 14. Interface qblade
The procedure required to obtain the generated power is as follows:
- Airfoil design - XFOIL Direct Anlysis - Polar extrapolation to 360° - HAWT Rotorblade Design - Rotor BEM Simulation
[7] F. Bertagnolio, N. S. Rensen, J. Johansen, Wind Turbine Airfoil Catalogue, RisØ-R-1280(EN), RisØ National Laboratory, Roskilde, Denmark, Agosto 2001
Airfoil design: Viewer Profiles. Ability to modify parameters (thickness, camber).
Figure 15. Airfoil design
XFOIL Direct Analysis: Analysis of coefficients (Cl, Cd) as Reynolds number will vary for each chord.
Polar extrapolation to 360°: Based on the graphs obtained in the previous section an extrapolation of the data of Cl and Cd for 360 ° angle of attack is created.
Rotor BEM Simulation: Preparation of Cp as a function of TSR using the BEM [8] theory. The aim is to get the greater Cp as the lowest TSR as possible to decrease the speed and noise caused.
Turbine BEM Simulation: Simulation of the power obtained. Range of wind speeds, rotation speed is defined and optimal TSR (maximum Cp obtained in the previous section) is obtained.
11STUDY METHODOLOGY The procedure carried out in this project is based on a series of tests for different suitable
airfoils for this type of wind turbines and different design configurations with which they seek to get the most power (nominal 30kW) at the lower wind speed possible as it is an urban location and the wind speeds will not be very high.
Necessary imput:Number of blades, Lambda(λ), Rotational speed (ω),Wind speed
(v), environmental conditions, wind turbine radius and chord.
The steps followed for the study of the different models are explained below, the calculations and results can be seen in paragraph 3 (test results) and Excel H30_chord_twist.
11.1 Aerodynamic Profiles
Among the many existing airfoils on the market have been selected are those commonly used in wind turbines based on the report Riso-R-1280 (EN), which were performed comparisons between different values of coefficients (Clift, Cdrag) with experimental measurements and code data calculation aerodynamic as EllipSys2D and XFOIL. . The QBladed program is based on XFOIL code. The selected airfoils have good performance for dirt accretion which is a good property while operating in an urban environment. Blades studies with these profiles have been carried out:
- Blade with airfoils DU 99W350, DU 97W300, DU93-W-210, NACA-63-415 y NACA 63-418
- Blade with airfoils S808, S807 y NACA 63-415 - Blade with airfoils FFA-W3-301, FFA-W3-241, NACA 63-418 Y NACA 63-415.
Airfoils have been chosen with a thickness between 12 and 15% at the tip and about 35% at the root since it must withstand the maximum moments of aerodynamic forces transmitted through the blade to the root.
Where is the angle of attack, r the radial position of the different sections of the blade, W the relative velocity, ω the rotational speed (70 rpm) and v the wind speed (8m/s).
The Betz limit indicates that only about 60% of the energy contained in the wind is
convertible into useful energy at the turbine. This limit is the which is obtained for coefficient equal to 1/3.
This method of calculating the twist gives very high results on the root so the first values
were changed by assigning more logical values, because the more twist the blade has, the more difficult is to make the mold.
11.3 Angle of attack An attack angle such that the lift coefficient in the pre-stall, next to the maximum lift
coefficient is chosen,hence it is convenient to define a greater consistency of the "chord".
Operating in the pre-stall zone, we have the advantage that when the wind speed increases, the lift coefficient remains in a range of acceptable values. Another implication is that operating in this zone, the solidity has reasonable values and the cost of fthe blade does not increase.
11.4 Chord law Blade with different chord methods have been made.
1. [9]
3. ; [10]
Where the shape parameter (SP) that is, depending on the speed ratio (SR) of the following graph.
As with the twist, these methods give very high values at the root, so these were reduced to more logical values based on other models of blade used in this type of wind turbines, and with the option to add a trendline in Excel, an equation for the chord will be obtained.
11.5 Reynolds number
To calculate the Reynolds number has taken the following procedure.
- Calculate the chord (c) by taking the maximum chord for each airfoil. - Calculate the relative velocity W.
With these final Reynolds number, the angle of attack can be choosen by the following procedurecl:
- In the QBlade program, in the analysis section, the final Reynolds number is entered. - In the cl-alpha curve, the angle of attack is studied as it is explained in paragraph 3.3.
Example: for DU 93-W210 airfoil, whose Reynolds number is 1.199.837, the angle of attack chosen is 9.7ᴼ.
Figura 23. Angle of attack of the DU 93-W210 airfoil
12TEST RESULTS Different blade models have been performed using NACA, DU, S and FFA airfoils and two
types of tips to produce pitching moment at blade root that will be used to move the pitch.
As starting hypothesis zero thickness at the trailing edge is assumed. This parameter will be modified once the thickness of the shells and the manufacturing conditions are known.
Then the airfoils will be modified in QBlade and the polar and the power curve will be recalculated.
Figure 24. First tip model (a) and second tip model (b)
d. DU and NACA profiles with the first chord method and the second tip model:
As explained before, the root values are very high and these have been modified to more logical values based on other models of blade used in this type of wind turbine, and with the option to add a trendline in Excel, an equation for the chord will be obtained.
Profile Cl α r λ Chord(m)
DU 99-W350 1.45 0.175 0.250 6.414 6.133
DU 99-W350 1.45 0.175 0.380 6.414 4.035
DU 97-W300 1.41 0.169 0.500 6.414 3.154
DU 97-W300 1.41 0.169 0.625 6.414 2.523
DU 97-W300 1.41 0.169 0.750 6.414 2.102
DU 97-W300 1.41 0.169 0.880 6.414 1.792
DU 97-W300 1.41 0.169 1.000 6.414 1.577
DU 97-W300 1.41 0.169 1.250 6.414 1.261
DU 97-W300 1.358 0.152 1.500 6.414 1.091
DU 97-W300 1.358 0.152 1.750 6.414 0.936
DU 97-W300 1.358 0.152 2.000 6.414 0.819
DU 97-W300 1.358 0.152105444 2.25 6.414085001 0.727630914
DU 93-W210 1.382 0.152314884 2.5 6.414085001 0.643495299
DU 93-W210 1.382 0.152314884 2.75 6.414085001 0.584995726
DU 93-W210 1.382 0.152314884 3 6.414085001 0.544046026
The final Reynolds number is calculated with this chord, then the alpha is chosen and the twist is calculated with the procedure explained in section 3.2.
As in the chord, the method to calculate the twist at the root gives very high scores (approximately 50-60ᴼ) so that the first 75 centimeters were modified, assigning lower values, because the more twist the blade has, the more difficult is to make the mold. Then, with the option to add a trendline in Excel, an equation for the twist will be obtained.
After the meeting with Poliplastas, project partner tasked with blades manufacturing, where it was reported that there are no problems with any of the two forms, it was decided that the shape of the blade tip would be the second since more is obtained with it.
Once made the different tests, the blade with profiles DU_NACA was chosen for the following reasons:
- These are the most commonly used profiles - As the turbine is destined to operate in urban environments, dirt and noise
emission should be considered. According to studies performed by the University of Delft [11], DU06-W-200 airfoil is suitable for this site for good behavior with the dirt and noise emission. The 63nnnNACA series are good for dirt too. [12]
- Result power coefficients ( ) of about 0,5 and powers provided are reached.
Among the various tests with these blade profiles, the blade with the best was chosen.
With the law of chord obtained in paragraph c of section 3 (test results), two different models were performed in which the difference is curved blade tip backward.
It was decide to put a circular profile in the first 25 centimeters to improve the structural behavior.
The possibility of increasing the size of the spinner will be evaluated to reduce losses in the root zone.
[11] Rooij-roughness_sensitivity_AIAA2003-0350 [12] R.J. Margarita, Influencia del ángulo de ataque,2004
The results of this project should be sent to three project partners. - Kth (noise study) - Poliplastas (manufacturers) - Cirse (generator and box) - Brian O’ Brian (aesthetic)
The changes that have been carried out to transform the initial model are:
Final model Initial model
H20 H30
ρ (Kg/ ) 1.225 1.225
μ ( ) 1.83 1.83
rpm 120 70
Number of blades 3 3
Blade length 3.65 7
Radius 4 7.35
Power ( ) 20 30
The main reasons for the last changes have been the limits in the budget to build the generators and the permitted urban noise levels. The noise analysis has been carried out by Trinity College Dublin, and the limitations regarding the generator by CIRCE and FORES.
The aim is to increase as much as possible the rotational speed to get smaller generators without overcome the noise limits for urban environment.
SWIP. H20 WIND TURBINE 77
16RESULTS 16.1 Blade geometry
Pos ( ) Chord ( ) Twist Profile
0 0.35 34.25 Circular
0.113 0.728 29.28 DU99-W350
0.249 0.67 24.94 DU97-W300
0.385 0.63 21.15 DU97-W300
0.521 0.58 17.88 DU97-W300
0.657 0.55 15.07 DU97-W300
0.793 0.52 12.66 DU97-W300
0.929 0.49 10.62 DU97-W300
1.065 0.47 8.9 DU97-W300
1.201 0.45 7.46 DU97-W300
1.337 0.44 6.26 DU97-W300
1.473 0.43 5.27 DU97-W300
1.609 0.42 4.45 DU93-210
1.745 0.411 3.78 DU93-210
1.881 0.407 3.23 DU93-210
2.017 0.403 2.77 NACA63-418
2.153 0.4 2.39 NACA63-418
2.289 0.397 2.06 NACA63-418
2.425 0.393 1.78 NACA63-418
2.562 0.388 1.53 NACA63-418
2.698 0.381 1.29 NACA63-418
2.834 0.372 1.07 NACA63-418
SWIP. H20 WIND TURBINE 78
2.866 0.369 1.02 NACA63-418
2.904 0.366 0.97 NACA63-418
2.970 0.359 0.86 NACA63-418
3.008 0.355 0.81 NACA63-418
3.040 0.351 0.75 NACA63-418
3.073 0.347 0.71 NACA63-418
3.106 0.35 0.66 NACA63-415
3.176 0.35 0.56 NACA63-415
3.242 0.35 0.46 NACA63-415
3.313 0.35 0.37 NACA63-415
3.378 0.35 0.28 NACA63-415
3.449 0.35 0.2 NACA63-415
3.514 0.35 0.13 NACA63-415
3.585 0.35 0.06 NACA63-415
3.617 0.35 0.03 NACA63-415
3.634 0.35 0.01 NACA63-415
3.65 0.35 0 NACA63-415
SWIP. H20 WIND TURBINE 79
The next Cp curve is obtained for the previous blade geometry:
Giving a and a λ equal to 0.46196 and 4.8 respectively.
Within the SWIP project, this report describes the process of aerodynamic study has been carried out to design the vertical axis wind turbine and rated at 2 kW (V2). This will be placed on the roof of a building in Choczewo, Poland.
Initially considered the possibility of placing upright but after studying several options it was decided to install it horizontally to maximize space and maximize the energy obtained. The Figure 2 shows how the wind flow is inclined. Taking into account the size of the place, the turbine will be 4.5 meters in length and 1 meter radius.
18.STUDY METHODOLOGY The procedure carried out in this project is based on some tests with different suitable
profiles for this VAWT. The aim is to get power rated (2 kW) at low wind speeds. At the site the average speed is 4 m/s. The steps followed are:
- Evaluation of possible aerodynamic profiles (dirt, manufacturability). - Study of selected profiles (Cl, Cd). - Study of number of blades (3, 4, 5, 6) - Chrod lenght (20, 30, 40, 50 y 60 centimetres). - Cl and Cd tables profiles for each Reynolds (chord). - Polar 360⁰ (interpolation to obtain Cl for 360⁰ of angle attack) - Geometry (Number of blades, profiles, sections, twist, size). - Cp, angle attack, and TSR (Tip speed ratio, ) - Power and aerodynamic loads on the rotor and blades.
Among the many existing airfoils on the market have been selected are those commonly used in wind turbines based on the report Riso-R-1280 (EN) [1], which were performed comparisons between different values of coefficients (Clift, Cdrag) with experimental measurements and code data calculation aerodynamic as EllipSys2D and XFOIL. Additionally, the airfoil DU06-W-200 has been studied because it is a airfoil designed specifically for Vertical Axis Wind Turbine (VAWT) [2] [3]. The program that is used is QBlade which is based on XFOIL code. These profiles have good performance under the dirt that may accumulate to be in an urban environment:
Each profile has been tested with different configurations by changing the length of the chord and the number of blades. Chords 20, 30, 40, 50 and 60 centimeters are studied with 3, 4, 5 and 6 blades, in total 20 test power with each airfoil.
20.POWER CURVE CALCULATION. QBLADE
The program used for the studies of power is QBlade [4], an open-source software distributed under GPL license. It integrates XFOIL, a tool for design and analysis of airfoils, which can be used to simulate a wind tunnel test to obtain the lift and drag coefficients (Cl, Cd).
Polar extrapolation to 360°: Based on the graphs obtained in the previous section, an extrapolation of the data of Cl and Cd for 360 ° angle of attack is created.
Figure 7. Polar extrapolation to 360°
VAWT Rotorblade Design: For the definition of the geometry 17 equidistant sections are defined. There is a 90° helical angle between chords of the first and last sections. The aim for this rotation is to minimize the noise caused when the blade passes in front of the wall. the number of blades is also introduced.
Rotor DMS Simulation: Theory DMS (Doble Multiple Streamtube) [5] to obtain the graph of the power coefficient (Cp) vs TSR. To minimize the noise, its necessary to use the minimum TSR possible. Design TSR matches with the maximum Cp.
Figure 9. Rotor DMS Simulation
Turbine DMS Simulation: Power simulation. Maximum and mínimum wind speed and rotor speed are defined for the design TSR.
The aim is to obtain maximum power at lower wind speed because it is an urban site with low mean wind speed (4 m/s). Each profile has 20 different configurations, and the configuration which produces more energy at low wind speed will be selected. Comparing the best configuration for each profile is possible to determine the optimum profile, chord length and the optimal number of blades.
As the turbine is destined to operate in urban environments, dirt and noise emission should be considered. According to studies performed by the University of Delft [2], DU06-W-200 airfoil is suitable for this site for good behavior with the dirt and noise emission. In Figure 15, this airfoil has a great power curve. A-AIRFOIL has only a small increase in power, but DU profile is better for these environmental conditions.
[1] N. S. R. J. J. F. Bertagnolio, Wind Turbine Airfoil Catalogue, RisØ-R-1280(EN),, Roskilde, Denmark: RisØ National Laboratory, August 2001.
[2] M. Claessens, The Design and Testing of Airfoils for Application in Small Vertical Axis Wind Turbines, Delf University of Tecnology, November 2009.
[3] R. Bos, Self-starting of a small urban Darrieus rotor, Delf University of Tecnology, November 2012.
[4] http://qblade.npage.de/
[5] I. PARASCHIVOIU, WIND TURBINE DESIGN with emphasis on Darrieus concept.
