3514120A-BEE
AVONMOUTH SEVERNSIDEENERGY MASTERPLANNINGREPORTTECHNO-ECONOMIC ANALYSIS
CONFIDENTIAL MAY 2016
Revision 2Confidential
Project no: 3514120A-BEEDate: May 2016
WSP | Parsons BrinckerhoffWSP House70 Chancery LaneLondonWC2 1AF
Tel: 020 7314 5000
www.wspgroup.comwww.pbworld.com
AVONMOUTH SEVERNSIDEENERGY MASTERPLANNINGREPORTFINAL ISSUESouth Gloucestershire Council
Q U A L I T Y M A N A G E M E N TISSUE/REVISION FIRST ISSUE REVISION 1 REVISION 2 REVISION 3
Remarks Draft for comment Commentsaddressed
Further commentsaddressed
Date 24/12/16 11/02/16 01/04/16
Prepared by Laurie Eldridge Laurie Eldridge Laurie Eldridge
Signature
Checked by Andrew Goodman
Bruce Geldard
Andrew Goodman
Bruce Geldard
Andrew Goodman
Signature
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Project number 3514120A-BEE 3514120A-BEE 3514120A-BEE
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P R O D U C T I O N T E A MWSP | PARSONS BRINCKERHOFF
Project Engineer Laurie Eldridge
Senior Project Engineer Andrew Goodman
Technical Director Bruce Geldard
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TABLE OF CONTENTS1 INTRODUCTION ...........................................................................1
2 HEAT DEMAND SUMMARY ........................................................22.1 Cribbs Patchway............................................................................ 22.2 New Earth to Accolade Wines ........................................................ 32.3 Southmead .................................................................................... 32.4 UWE.............................................................................................. 4
3 HEAT DEMAND PROFILING .......................................................5
4 PIPELINE MODELLING ...............................................................84.1 Estimation of peaks ....................................................................... 84.2 Pipeline modelling ........................................................................114.3 Outputs ........................................................................................12
5 CHP SIZING................................................................................175.1 New Earth Solutions .....................................................................18
6 THERMAL STORE SELECTION ................................................20
7 OTHER TECHNICAL INPUT TO THE MODELLING ..................237.1 Carbon Factors .............................................................................237.2 Restrictions on number of starts ....................................................237.3 Boiler Efficiencies .........................................................................237.4 Energy Centre Parasitic Loads......................................................23
8 FINANCIAL ANALYSIS ..............................................................248.1 Rationale ......................................................................................248.2 Capex ...........................................................................................248.3 CHP CAPEX and maintenance .....................................................248.4 Energy centre size ........................................................................258.5 Consumer side costs ....................................................................258.6 New development heat networks ..................................................268.7 Other capex ..................................................................................268.8 Summary of CAPEX .....................................................................268.9 Maintenance .................................................................................278.10 Replacement costs (Repex) ..........................................................27
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8.11 Operating income .........................................................................288.12 Consumer unit maintenance, metering and billing costs ................298.13 Heat Sales Prices .........................................................................298.14 Electricity sales .............................................................................308.15 Electrical import and gas ...............................................................308.16 Purchase of heat from New earth Solutions ..................................318.17 Variation through time ...................................................................318.18 CRC and other carbon taxation schemes ......................................318.19 RHI ...............................................................................................31
9 FINANCIAL RESULTS ...............................................................329.1 Cribbs ...........................................................................................329.2 New Earth Solutions .....................................................................329.3 Southmead ...................................................................................339.4 UWE.............................................................................................34
10 SENSITIVITY TO KEY LOADS – UWE NETWORK ...................3510.1 Introduction – linear heat density modelling ...................................3510.2 Linear heat density results ............................................................3510.3 Load Profiling ...............................................................................3710.4 Pipeline Modelling ........................................................................3710.5 CHP modelling .............................................................................3810.6 Financial inputs.............................................................................3910.7 Energy centre size ........................................................................3910.8 Consumer side costs ....................................................................3910.9 Summary of CAPEX .....................................................................3910.10 Financial results............................................................................40
11 SOUTHMEAD NETWORK – FURTHER ANALYSIS .................41
12 FINANCIAL SENSITIVITY ..........................................................4312.1 Energy costs / Prices ....................................................................4312.2 Effect of RHI .................................................................................43
13 CARBON SAVINGS ...................................................................44
14 CONCLUSIONS ..........................................................................45
15 STRATEGIC NETWORK ASSESSMENT ..................................4615.1 Introduction ..................................................................................46
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15.2 Methodology .................................................................................4615.3 Heat Supply – Capacity and Costs ................................................4615.4 Heat Loads and Network Route ....................................................4815.5 Capital Cost Estimates..................................................................5215.6 Potential Volume Of Heat Supply ..................................................5915.7 Value Of Heat Supply ...................................................................6015.8 Potential Return On Investment And Carbon Savings ...................60
16 APPENDIX A: HEAT DEMAND PROFILES ...............................65
17 APPENDIX B: CONSUMER SIDE COST SUMMARY ...............78
18 APPENDIX C: PHASED AVONMOUTH SEVERNSIDENETWORK DEVELOPMENT .....................................................80
19 APPENDIX D: PROCESS STEAM USE IN THE VICINITY OFSERC ..........................................................................................87
20 APPENDIX E: NEW EARTH SOLUTIONS .................................8920.1 Business Changes ........................................................................89
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T A B L E STABLE 2-1: HEAT DEMANDS CRIBBS PATCHWAY ......................................................... 2TABLE 2-2: BENCHMARKED HEAT DEMANDS – CRIBBS PATCHWAY .......................... 3TABLE 2-3: HEAT DEMANDS – NEW EARTH TO ACCOLADE WINES ............................. 3TABLE 2-4: HEAT DEMANDS - SOUTHMEAD .................................................................. 3TABLE 2-5: BENCHMARKED HEAT DEMANDS -SOUTHMEAD ....................................... 4TABLE 2-6: HEAT DEMANDS - UWE ................................................................................ 4TABLE 2-7: BENCHMARKED HEAT DEMANDS - UWE .................................................... 4TABLE 4-1: SUMMARY OF LOAD FACTORS .................................................................... 8TABLE 4-2: CRIBBS PATCHWAY PEAK HEAT DEMANDS .............................................. 8TABLE 4-3: ACCOLADE WINES HEAT PEAK DEMANDS ................................................. 9TABLE 4-4: SOUTHMEAD NETWORK PEAK HEAT DEMANDS........................................ 9TABLE 4-5: UWE NETWORK PEAK HEAT DEMANDS ...................................................... 9TABLE 4-6: HIU RATINGS ............................................................................................... 10TABLE 4-7: FLOW AND RETURN TEMPERATURES ...................................................... 12TABLE 4-8: SUMMARY OF PIPELINE MODELLING OUTPUTS ...................................... 12TABLE 5-1: SUMMARY OF CHP SIZES .......................................................................... 17TABLE 5-2: SUMMARY OF CHP PERFORMANCE ......................................................... 17TABLE 8-1: CHP CAPEX ................................................................................................. 24TABLE 8-2: ENERGY CENTRE ESTIMATED FLOOR AREA ........................................... 25TABLE 8-3: SUMMARY OF CONSUMER SIDE COSTS .................................................. 25TABLE 8-4: OTHER CAPEX ............................................................................................ 26TABLE 8-5: SUMMARY OF CAPEX ................................................................................. 26TABLE 8-6: MAINTENANCE COSTS ............................................................................... 27TABLE 8-7: REPEX COSTS............................................................................................. 28TABLE 8-8: HEAT SALES PRICES .................................................................................. 29TABLE 10-1 LINEAR HEAT DENSITY TESTING (LIST) ................................................... 36TABLE 10-2: CORE UWE CHP CAPEX ........................................................................... 39TABLE 10-3: ENERGY CENTRE ESTIMATED FLOOR AREA ......................................... 39TABLE 10-4: SUMMARY OF CAPEX ............................................................................... 39TABLE 13-1: ANTICIPATED CARBON SAVINGS ............................................................ 44TABLE 15-1: CAPITAL COSTS SCENARIO 1 ALL CLUSTERS - SERC AND NES .......... 55TABLE 15-2: CAPITAL COSTS - SCENARIO 2 ALL CLUSTERS - SERC ONLY ............ 56TABLE 15-3: SCENARIO 3 – CAPITAL COSTS CPNN AND SOUTHMEAD ONLY -
SERC ONLY ................................................................................... 57TABLE 15-4: CAPITAL COSTS - SCENARIO 4 - CPNN ONLY - SERC ONLY ................. 58TABLE 15-5: CAPITAL COSTS - SCENARIO 5 – UWE TO CITY CENTRE LINK -
SERC ONLY ................................................................................... 59TABLE 15-6: DHW AND SPACE HEATING PROFILES ................................................... 65TABLE 15-7: CRIBBS PATCHWAY ESTIMATED CIU COSTS ......................................... 78TABLE 15-8: ACCOLADE WINES ESTIMATED CIU COSTS ........................................... 78TABLE 15-9: SOUTHMEAD NETWORK ESTIMATED CIU COSTS .................................. 78TABLE 15-10: UWE NETWORK ESTIMATED CIU COSTS .............................................. 79
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F I G U R E SFIGURE 3-1: CRIBBS PATCHWAY NETWORK ................................................................. 6FIGURE 3-2: ACCOLADE WINES HEAT DEMAND PROFILE ............................................ 6FIGURE 3-3: SOUTHMEAD NETWORK HEAT DEMAND PROFILE .................................. 7FIGURE 3-4: UWE NETWORK HEAT DEMAND PROFILE ................................................ 7FIGURE 4-1: DOMESTIC HOT WATER DIVERSITY FACTORS ...................................... 11FIGURE 4-2: CRIBBS PATCHWAY SCHEME .................................................................. 13FIGURE 4-3: NEW EARTH SOLUTIONS ......................................................................... 14FIGURE 4-4: SOUTHMEAD ............................................................................................. 15FIGURE 4-5: UWE 16FIGURE 6-1: CRIBBS PATCHWAY THERMAL STORE SELECTION .............................. 20FIGURE 6-2: SOUTHMEAD THERMAL STORE SELECTION .......................................... 21FIGURE 6-3: UWE THERMAL STORE SELECTION ........................................................ 21FIGURE 9-1: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, CRIBBS
PATCHWAY .................................................................................... 32FIGURE 9-2: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, NEW EARTH
SOLUTIONS ................................................................................... 33FIGURE 9-3: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, SOUTHMEAD ......... 33FIGURE 9-4: 25-YEAR CUMULATIVE DISCOUNTED CASHFLOW, UWE ....................... 34FIGURE 10-1 LINEAR HEAT DENSITY RESULTS .......................................................... 36FIGURE 10-2: CORE UWE NETWORK PROFILE THROUGH THE YEAR ....................... 37FIGURE 10-3: CORE UWE NETWORK ........................................................................... 38FIGURE 10-4: DISCOUNTED CUMULATIVE CASHFLOW – CORE UWE SCHEME ....... 4011-1: SOUTHMEAD NETWORK LINEAR HEAT DENSITY ............................................... 41FIGURE 15-1: SERC TO ALL CLUSTERS ....................................................................... 51FIGURE 15-2: ROUTE FROM UWE CLUSTER TO THE CITY CENTRE (TEMPLE &
REDCLIFFE EC IN ST PHILIPS) ..................................................... 52FIGURE 18-1: 2019 NETWORK ....................................................................................... 81FIGURE 18-2: 2021 NETWORK ....................................................................................... 82FIGURE 18-3: 2023 NETWORK ....................................................................................... 83FIGURE 18-4: 2025 NETWORK ....................................................................................... 84FIGURE 18-5: 2027 NETWORK ....................................................................................... 85FIGURE 18-6: 2029 NETWORK ....................................................................................... 86
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1 INTRODUCTIONThis report builds on the Avonmouth & Severnside Heat Network Study – Heat Mapping Reportcompleted by WSP | Parsons Brinckerhoff (WSP | PB). Within this previous report, which formedthe first phase of a study examining the potential for decentralised energy networks within theAvonmouth-Severnside area of South Gloucestershire, a number of heat clusters with thepotential for decentralised energy networks were identified. Following a workshop to discussthese, four potential heat clusters were identified for further analysis:
à Cribbs Patchway
à New Earth Solutions to Accolade Wines
à Southmead
à UWE
This report focuses on more detailed modelling of each of these clusters. This is set out in thefollowing sections:
à Heat Demand Summary: Summarises heat demands as set out in the heat mapping report.Also includes benchmarks for those loads for which no demands had been available.
à Load profiling: Heat demands were collected in the form of kilowatt-hours per annum. Inorder to model the operation of a CHP engine against these demands, it is necessary to havethe variation throughout the year. This section sets out the process by which annual demandswere converted into hourly profiles.
à CHP sizing: This section focuses on the selection of an appropriately sized CHP engine tomeet the heat demands.
à Pipeline modelling: WSP | PB’s bespoke model was used to size and cost the pipe networkrequired to supply the heat loads. This includes estimation of peak heat demands for each ofthe loads on the network.
à Financial modelling: A full financial model was undertaken for each of the networks, in orderto establish economic viability.
à Sensitivity analysis: Financial sensitivity to key criteria.
à Update of strategic network assessment: Following on from the initial heat networksproposition in the previous heat mapping report.
à Conclusions and recommendations
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2 HEAT DEMAND SUMMARYThis section sets out the loads which comprise each of the four clusters, as identified within theHeat Mapping Report:
à Cribbs Patchway
à New Earth to Accolade Wines
à Southmead
à UWE
2.1 CRIBBS PATCHWAY
The following heat demands were collected for the Cribbs Patchway cluster:
Table 2-1: Heat demands Cribbs Patchway
Site Name Heat demand (kWh/yr)Aztec Hotel & Spa UnavailableCPNN - residential 14,166,000CPNN - non-residential 21,305,000Callicroft Primary School 185,000Hilton Bristol Hotel UnavailableHoly Family Primary School 140,000Patchway Community School 1000,000Patchway Locality Hub 200,000Rolls Royce 7,000,000St Chad's Primary School 120,000Stoke Lodge Primary School 200,000
For those loads where no heat demand was available, the following process was used to derivean estimate:
à Area of building and number of storeys established using Google Maps to give overallexternal floor area
à Heat benchmark applied based on CIBSE Guide TM46 fossil fuel benchmarks and anassumed boiler efficiency of 80%
à Total building heat demand calculated.
It should be noted that this is a fairly crude approach and more refined data would need to begathered at the next stage of design. However, these heat demands are sufficient at this high-level feasibility stage.
The calculations undertaken are set out below:
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Table 2-2: Benchmarked heat demands – Cribbs Patchway
Site Name
Area fromGoogle Maps(m2)
Numberof floors Use type
Benchmark(2006)(kWh/m2/yr)
Benchmarkedheat demand(kWh/annum)
Aztec Hotel &Spa 5500 2.5 Hotel 264 3,630,000Hilton BristolHotel 6200 2 Hotel 264 3,274,000
2.2 NEW EARTH TO ACCOLADE WINES
This is a very small network which provides a link between the New Earth Solutions renewableenergy plant and Accolade Wines. As the New Earth Solutions plant is solely providing (i.e. notusing) heat, there is no associated demand listed.
It is noted that there are other potential heat demands in this area but these are, in the main,small privately owned businesses. Typically it could be expected that such loads might join anetwork that is already in operation but would not be relied on as part of a base case businessplan. We have therefore not included these in the demands identified at this stage.
Table 2-3: Heat demands – New Earth to Accolade Wines
Site Name Heat demand (kWh/annum)Accolade Wines 4,165,000New Earth N/A
2.3 SOUTHMEAD
Heat demands collated for the Southmead network are summarised in the table below:
Table 2-4: Heat demands - Southmead
Site NameHeat demand(kwh/annum)
Badocks Wood Primary - Southmead Childrens’ Centre 120,000BAE systems 1,094,000Charborough Road Primary School 170,000Filton Sports & Leisure Centre UnavailableHorfield Leisure Centre 1,518,000South Gloucestershire & Stroud College UnavailableSouthmead Hospital 28,508,000
One of the potential additional loads on this network is Airbus. This has a significant heat demandof 22.8GWh – and so could nearly double the heat demands. It has been excluded as it is nowunderstood that the campus has a fully decentralised heating system with around 500 differentcombustion appliances mainly in the 10-500kW range. Many are warm air or other types notreadily converted to L/MPHW without significant expenditure.
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A benchmarking process was followed to establish heat demands for the remaining loads, as setout in Section 2.1. The outcomes of the benchmarking are set out in the table below:
Table 2-5: Benchmarked heat demands -Southmead
Site Name
Area fromGoogleMaps
Number offloors Use type
Benchmark(2006)(kWh/m2/yr)
Benchmarked heatdemand(kWh/yr)
Filton Sports & LeisureCentre 2400 1
Sportscentre(dry) 264 633,600
South Gloucestershire& Stroud College 8750 3 School 120 3,150,000
2.4 UWE
Heat demands of the network in and around UWE are summarised in the table below:
Table 2-6: Heat demands - UWE
GIS ID Heat demand (kWh/annum)Bristol Rovers/ UWE stadium 4,980,000Frenchay Hospital 2,936,000Harry Stoke 7,245,000Hewlett Packard 1,523,000Higher Education Funding Council NoneHoliday Inn Bristol-Filton NoneLand East of Coldharbour Lane 2,818,000Land East of Harry Stoke 11,986,000MoD Filton Abbey Wood 8,994,000Romney House 289,000UWE 6,768,000
The outputs from benchmarking are summarised in the table below:Table 2-7: Benchmarked heat demands - UWE
GIS ID
AreafromGoogleMaps
Numberoffloors
Usetype
Benchmark(2006)(kWh/m2/yr)
Benchmarkedheat demand(kWh/annum)
Higher Education Funding Council 1500 3 Office 96 432,000Holiday Inn Bristol-Filton 6250 2 Hotel 264 3,300,000
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3 HEAT DEMAND PROFILINGIt is proposed that the clusters are initially supplied with heat from gas-fired CHP engines, withback up and peaking heat supplied by gas boilers. Gas-fired CHP is proposed as the base casefor feasibility: it is a well-proven, reliable technology, with engines available from a wide range ofmanufacturers. Compared to biomass solutions, it is low risk from a planning / fuel supply andstorage perspective.
The hourly variation in heat demand throughout the year is used to assess the operation of theCHP engines, and select appropriately sized models. Annual heat demands were thereforeconverted into hourly heat profiles using WSP | PB’s in-house load profiling tool.
This tool uses assumed daily heat demand profiles for space heating and domestic hot water(DHW), with separate profiles for weekday and weekend demands and an assumed percentagesplit between the two. Hot water demands are assumed to remain constant throughout the year,whilst space heating demands vary inversely with external temperature (it is assumed that heatingis required once the external temperature drops below 15.5°C)
The following main use types were used for profiling purposes:
à Hospital
à Hotel
à Leisure centre (with pool)
à Leisure centre (dry)
à Residential
à Office
à Stadium
à School
à University uses1
In addition, particular profiles were developed for Accolade Wines and the BAE Filton CribbsPatchway New Neighbourhood development.
These profiles are illustrated in appendix A.
1 Comprising offices, refectory, student union and student accommodation.
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The resultant annual profiles for the four networks set out above are illustrated in the subsequentdiagrams:
Figure 3-1: Cribbs Patchway Network
Figure 3-2: Accolade Wines heat demand profile
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10,000
20,000
30,000
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70,0001
267
533
799
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1331
1597
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2129
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6119
6385
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8513
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Cribbs Patchway network
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4179
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Hour through year
Accolade Wines
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Figure 3-3: Southmead Network heat demand profile
Figure 3-4: UWE network heat demand profile
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6273
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Southmead network
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Hour through year
UWE Network
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4 PIPELINE MODELLING4.1 ESTIMATION OF PEAKS
Decentralised energy pipe networks need to be sized in order to serve the peak loads which willbe encountered. The higher the peak demand, the larger the pipe diameter required. Peak loadswere derived from the annual loads presented in Section 2; the methodology is set out in thefollowing two sections.
NON-DOMESTIC LOADS
To convert from annual heat demands (in kWh) to peak heat demands (kW), load factors wereapplied. Load factors are given by the following equation:
= ℎ ( ℎ)
ℎ × 8760
i.e it is a representation of the “peakiness” of the heat demand throughout the course of a year.
Load factors were derived from the daily space heating and DHW profiles set out in the previoussection and are summarised in the table below:
Table 4-1: Summary of Load Factors
Use type Overall load factorAccolade Wines 90%Hospital 28%Hotel 15%Leisure Centre (With Pool) 33%Office 7%Stadium 15%School 8%Sports centre (dry) 13%UWE - office use 10%UWE - refectory 16%UWE – Student halls of residence 20%UWE – Student Union 15%BAE Filton - CPNN - non-residential 11%
Applying these load factors to the annual figures for each load leads to the following totals foreach network:
Table 4-2: Cribbs Patchway Peak Heat Demands
Site NameAnnual heatdemand (MWh) Load factor
Peak heatdemand (MW)
Aztec Hotel & Spa 3,630 15% 2.76BAE Filton - CPNN - residential 14,166 N/A Residential
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BAE Filton - CPNN - non-residential 21,305 11% 22.11Callicroft Primary School 185 8% 0.26Hilton Bristol Hotel 3,274 15% 2.49Holy Family Primary School 140 8% 0.20Patchway Community School 1,000 8% 1.43Patchway Locality Hub 200 7% 0.33Rolls Royce 7,000 7% 11.42St Chad's Primary School 120 8% 0.17Stoke Lodge Primary School 200 8% 0.29
Table 4-3: Accolade Wines Peak Heat Demands
Site NameAnnual heatdemand (MWh) Load factor
Peak heatdemand (MW)
Accolade Wines 4165 90% 0.53
Table 4-4: Southmead Network Peak Heat Demands
Site NameAnnual heatdemand (MWh) Load factor
Peak heatdemand (MW)
Badocks Wood Primary - SouthmeadChildrens Centre 120 8% 0.17
BAE systems 1,094 7% 1.79Charborough Road Primary School 170 8% 0.24Filton Sports & Leisure Centre 634 13% 0.56Horfield Leisure Centre 1,518 33% 0.53South Gloucestershire & StroudCollege 3,150 8% 4.50
Southmead Hospital 28,508 28% 11.62
Table 4-5: UWE Network Peak Heat Demands
GIS IDAnnual heatdemand (MWh) Load factor
Peak heatdemand (MW)
Bristol Rovers/ UWE stadium 4,980 15% 3.82Frenchay Hospital 2,936 N/A ResidentialHarry Stoke 7,245 N/A ResidentialHewlett Packard 1,523 7% 2.48Higher Education Funding Council 432 7% 0.71Holiday Inn Bristol-Filton 3,300 15% 2.51Land East of Coldharbour Lane 2,818 N/A ResidentialLand East of Harry Stoke 11,986 N/A Residential
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MoD Filton Abbey Wood 8,993 7% 15.67Romney House 289 7% 0.47
UWE2
Office use 2,835 10% 3.24
Refectory Use 193 16% 0.14
Student halls 3,561 20% 2.03
Student union 179 15% 0.14
DOMESTIC LOADS
Domestic peak loads are calculated in a different manner to non-residential loads. This isbecause significant diversity in demands for hot water needs to be taken into account. Forexample, while the units in a block of flats will have similar heat demand profiles, each dwellingwill experience its peak demand at a slightly different time. As such, the peak domestic demandon the network will be lower than that calculated by multiplying the number of dwellings by theper-dwelling peak heat demand.
The following peak demands are assumed per dwelling, based on typical heat interface unitratings:
Table 4-6: HIU ratings
Peak space heating demand 3.5 kW
Peak DHW demand 30 kW
The diversity curve of hot water consumption is developed from data provided in technical DHguidance for designers (Standard DS 439:2009), and is illustrated below:
2 Note: Demands for UWE shown here are taken from work carried out by WSP | PB for UWE, August 2015
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Figure 4-1: Domestic hot water diversity factors
The resultant diversified peak heat demands are summarised in the table below:
Table 4-7: Diversified peak residential demands, Cribbs Patchway
Site NameAnnual heatdemand (MWh)
Peak heat demand(MW)
BAE Filton - CPNN - residential 14,166 36.10
Table 4-8: Diversified peak residential demands, UWE
GIS IDAnnual heatdemand (MWh)
Peak heat demand(MW)
Frenchay Hospital 2,936 2.57Harry Stoke 7,245 6.10Land East of Coldharbour Lane 2,818 2.83Land East of Harry Stoke 11,986 10.17
4.2 PIPELINE MODELLING
WSP | PB’s proprietary pipeline model was used to model the pipe networks. This allows thediameter of pipe lengths to be calculated, DH network pumps to be sized, and indicative heat lossand network cost to be calculated.
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The inputs to the model are peak heat demand for each load connected to the network, flow andreturn temperatures, and network geometry.
Flow and return temperatures are here reproduced from the London Heat Network Manual3,which sets out best practice in this area.
The following flow and return temperatures are used, these are based on a combination of theLondon Heat Network Manual and WSP | PB’s experience of best practice in the construction ofdecentralised energy networks:
Table 4-9: Flow and return temperatures
Temperature Source
Primary flow 90°C District heating manual for London4
Primary return (Domestic space heating) 55°C District heating manual for London
Primary return (DHW) 25°C District heating manual for London
Primary return (non-domestic hot water) 55°C District heating manual for London
Non-domestic buildings can accept higher primary side temperatures, with temperatures of up to110°C standard. If residential developments are served by hydraulically separated networkswhich in turn serve each property, then higher temperature flow in primary mains is possible,which will increase temperature differentials and minimise pipe diameters. On the other hand,heat losses will be higher, therefore higher temperatures would only be used when demands arehigh - for example when outside temperatures are below 5°C – so as to minimise heat lossesthrough the year. The potential for such improvements would be considered in future, moredetailed, feasibility studies.
4.3 OUTPUTS
The table below summarises the outputs from pipeline modelling. Series 2 insulation5 has beenassumed throughout.
Table 4-10: Summary of pipeline modelling outputs
Network option Network cost Total trenchlength (m)
Total load atenergy centre(MWth)
Pumppower(kWe)
Annual heatlosses(MWh/annum)
Cribbs Patchway £8,450,000 7498 20.8 252 2194
New Earth Solutions £1,316,000 1507 1.3 6 355
Southmead £5,117,000 5543 6.1 41 1464
UWE £7,647,000 8265 47.3 396 2386
Indicative pipe diameters for the networks are shown in the following diagrams and tables. Theseshow the pipe to the boundary of each stakeholder, and are schematics only.
3 http://www.londonheatmap.org.uk/Content/uploaded/documents/LHNM_Manual2014Low.pdf4 The DH manual for London recommends a temperature of 110-80°C. 90°C has been selected here as the
maximum safe temperature for hot water to enter dwellings.5 Three insulation levels are available – 1, 2 and 3, of which 3 is the highest and 1 the lowest. Series 2 is
generaly recommended for projects in the UK.
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Figure 4-2: Cribbs Patchway Scheme
Diameters(nominal) (mm ID)
Cost per m(trench) (£
capex)
Length of this diameter in thisoption (m)
Total cost for pipediameter (£)
50 £638 760 £484,615
65 £690 1,039 £716,809
80 £753 - £0
100 £873 24 £21,084
125 £979 1,284 £1,257,514
150 £1,099 126 £138,683
200 £1,232 788 £970,435
250 £1,380 2,204 £3,040,991
300 £1,430 1,273 £1,819,767
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Figure 4-3: New Earth Solutions6
Diameters(nominal) (mm ID)
Cost per m(trench) (£
capex)
Length of this diameter in thisoption (m)
Total cost for pipediameter (£)
65 £690 1,507 £1,039,830
6 Please note that while shorter routes may be feasible to connect these loads we are not currently able toguarantee this and so have taken a conservative position for this high level study. We also note that thislonger route may provide additional opportunities for other loads to connect particularly on the businessparks at the junction of St Andrews Rd and Kings Weston Lane
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Figure 4-4: Southmead
Diameters(nominal) (mm ID)
Cost per m(trench) (£
capex)
Length of this diameter in thisoption (m)
Total cost for pipediameter (£)
50 £638 995 21,50265 £690 1,579 38,66480 £753 214 5,512100 £873 - -125 £979 - -150 £1,099 1,219 43,581200 £1,232 1,536 57,908
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Figure 4-5: UWE
Diameters(nominal) (mm ID)
Cost per m(trench) (£
capex)
Length of this diameter in thisoption (m)
Total cost for pipediameter (£)
65 £690 1,079 £744,51880 £753 30 £22,230100 £873 - £0125 £979 2,018 £1,976,475150 £1,099 1,039 £1,141,800200 £1,232 1,818 £2,239,428250 £1,380 1,814 £2,502,772300 £1,430 25 £36,050350 £1,584 442 £699,501
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5 CHP SIZINGThe Cribbs Patchway, Southmead and UWE networks are to be provided with heat from aCombined Heat and Power (CHP) engine during the initial stages of the project (i.e. before a linkto a waste heat supply is implemented). The one exception is the network which links New EarthSolutions and Accolade Wines – here heat is provided from the Energy from Waste plant at theformer.
Initial CHP size was calculated assuming that the CHP meets 70% of annual heat demand over6,000 hours. This is a rough, first-pass indicator which has been found by WSP | PB to indicate asuitable starting point for CHP selection, and provides a good base figure for testing differentsizes. This formula is set out below:
= ℎ × 70%
6000
The resultant sizes are set out in the table below, alongside the engines modelled.
Table 5-1: Summary of CHP sizesNetwork Annual heat
demand (GWh)Estimated CHPsize (kW)
CHP(s)modelled
Option heatoutput (kW)
Cribbs Patchway 51.2 5,980 2 x J6162 x J620J620 & J616
529266005946
New Earth 4.2 N/A N/A N/A
Southmead 35.2 4,110 2 x J4202 x J6122 x J616
292839705292
UWE 51.2 5,980 2 x J6122 x J616J616 & J612
397052925946
The performance of the CHPs listed in the table above is set out below:
Table 5-2: Summary of CHP performance
Engine name Electrical output (kW)Thermal output(kW) Energy input kW(gross)
J420 1487 1464 3,916J612 2000 1985 5,068J616 2679 2646 6,756J620 3352 3300 8,440J624 4401 4108 10,709
Initial modelling of the different CHP options against the heat loads showed that the followingCHPs performed best against the loads in terms of heat output and run hours:
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Table 5-3: Summary of CHPs modelledNetwork Annual heat
demand (GWh)Estimated CHPsize (kW)
CHP(s)modelled
Option heatoutput (kW)
Cribbs Patchway 51.2 5,980 2 x J620 6600New Earth 4.2 N/A N/A N/ASouthmead 35.2 4,110 2 x J612 3970UWE 51.2 5,980 2 x J616 5292
These engines were thus taken forwards to the next stage of modelling.
5.1 NEW EARTH SOLUTIONS
As already discussed, it is proposed that Accolade Wines receives heat from New EarthSolutions. The potential heat supply from New Earth Solutions is greater than the peak demand atAccolade and so should be able to supply the total heat demand except for during periods ofmaintenance. It is therefore assumed that 90% of Accolade Wines’ heat demand is met in thisway. The remaining 10% is assumed to be served from existing gas boilers at Accolade Wines
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6 THERMAL STORE SELECTIONThe use of thermal storage can improve CHP operation through decoupling heat demand andsupply. This means that at times when heat demand is greater than CHP output, heat can bedrawn down from the thermal store without the need to operate top up boiler plant. When demandis less than CHP output, excess heat can be used to charge the store, leading to a smoother CHPoperating regime (i.e. the engine does not need to switch on and off so frequently).
In order to select an appropriate store size, for each scheme CHP option, a range of thermal storecapacities was modelled, from 0 to 500m3. Two graphs are displayed below: one showing theeffect of varying thermal store size on the heat output from the CHPs, and the second showingthe effect on number of starts (based on a maximum of two starts per day). Engine restartsincrease the ‘wear and tear’ on an engine, and are hence undesirable in general. Graphs showingnumber of starts and overall heat output against thermal store size are set out below.
Figure 6-1: Cribbs Patchway Thermal Store Selection
-
200
400
600
800
1,000
1,200
30,000,000
30,500,000
31,000,000
31,500,000
32,000,000
32,500,000
33,000,000
33,500,000
34,000,000
- 100 200 300 400 500 600
Com
bine
dst
arts
pera
nnum
CHP
heat
outp
ut(k
Wh/
annu
m)
Thermal store size (m3)
Cribbs Network - Effect of Changing TS size
Total heat supply Total starts
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Figure 6-2: Southmead thermal store selection
Figure 6-3: UWE thermal store selection
The trend of the curves illustrated above shows that with increasing thermal store size, thenumber of annual restarts decreases, whilst overall annual heat output increases. Enginesuppliers would typically limit restarts to a maximum of 2 per day in maintenance contracts, andthe use of thermal storage will help to achieve this whilst maintaining a higher level of heatrecovery. A greater number of restarts will have an impact on guarantees on availability andincrease maintenance costs.
Another key consideration is the financial implications of thermal storage. Although increasingthermal store size leads to overall financially beneficial outcomes, these need to be set off againstthe capital cost of the store.
0.00
50.00
100.00
150.00
200.00
250.00
300.00
21,800,000
21,900,000
22,000,000
22,100,000
22,200,000
22,300,000
22,400,000
22,500,000
22,600,000
0 100 200 300 400 500 600 700
Com
bine
dst
arts
pera
nnum
CHP
heat
outp
ut(k
Wh/
annu
m)
Thermal store size (m3)
Southmead Network - Effect of Changing TS Size
Total heat output Total starts
0.00
100.00
200.00
300.00
400.00
500.00
600.00
700.00
800.00
25,500,000
26,000,000
26,500,000
27,000,000
27,500,000
28,000,000
28,500,000
29,000,000
29,500,000
- 100 200 300 400 500 600
Com
bine
dst
arts
pera
nnum
CHP
heat
outp
ut(k
Wh/
annu
m)
Thermal store size (m3)
UWE Network - Effect of Changing TS Size
Total heat output Total starts
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Looking at the UWE network, increasing the thermal store size by 20m3 at an extra CAPEX of£20,000 leads to an extra £1200 income per year, so a payback period of around 17 years. It isnoted that these costs and revenues are quite conservative at this stage and a further moredetailed assessment of the benefits of large thermal stores should be undertaken in next stagestudies.
In particular it is known that larger stores will have a lower per m3 capital cost and that CHPmaintenance costs are quite sensitive to hours of operation. The potential for load shifting – iegenerating electricity when market values are high, whilst storing heat for use at night whenelectricity is cheaper, should also be considered. Finally, a future assessment of the benefit oflarger thermal storage for the strategic network should be considered.
As such, it is proposed for this study to keep the size of the thermal store at a minimum, with sizeselected primarily to avoid an excessive number of starts. Using this rationale leads to thefollowing thermal store selections:
Network Selected thermal store size (m3)
Cribbs 150
Southmead 100
UWE 150
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7 OTHER TECHNICAL INPUT TO THEMODELLINGThis section summarises all other technical inputs to the modelling.
7.1 CARBON FACTORS
DEFRA emissions factors for company reporting are used. These are:
à 0.50029kgCO2/kWh for electricity
à 0.18639kgCO2/kWh for gas
7.2 RESTRICTIONS ON NUMBER OF STARTS
All CHPs modelled were restricted to two starts per day. Additional starts create extra wear on theengine and increase maintenance costs
7.3 BOILER EFFICIENCIES
We have assumed that the efficiency of new top-up boilers is 85%.
7.4 ENERGY CENTRE PARASITIC LOADSThe predominant parasitic load at the energy centre is for pumping demands. These are set out inTable 4-10.
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8 FINANCIAL ANALYSIS8.1 RATIONALE
As has been mentioned, the heat clusters set out within this report form the constituent parts of awider Avonmouth-Severnside heat network. In order to facilitate these networks to link up at afuture date, the following approach is taken:
à Containerised CHP, allowing the engine to be removed when a wider network develops, fedfrom SERC or another lower carbon heat source. However, each cluster still retains apurpose-built energy centre, which contains top-up boilers, pumps, etc. and will providepeaking supply to the cluster in the wider network case.
à Boiler plant is assumed to be retained at UWE and the MoD. In the former case, this followsthe approach taken by UWE in terms of their approach of distributed plant rooms whenimplementing CHP on the campus. In the case of the latter, it is assumed that the MoD wouldrequire some degree of control to be retained over their heat supply.
8.2 CAPEX
Indicative energy centre costs are based on the following items:
Item Cost Source
CHP engine See Table 8-1 Costs based on supplierquotes
Thermal storage £1,000 per cubic metre Based on quotes fromsuppliers
Utility Connections £195,000 per network EstimateEnergy centre building £1650/m2. Building costs are based on
the space requirements of theenergy centre plant.
Mechanical processes andcontrols
£90 per kW installed capacity Spon’s all-in gas fired boilercost of £91 to £99 per kW.Includes gas train, controls,flue, plantroom pipework,valves and insulation, pumpsand pressurisation unit.
Distribution pipework Costs set out in Table 4-10.
8.3 CHP CAPEX AND MAINTENANCE
CHP CAPEX is listed in the table below. For the sake of convenience, maintenance costs areprovided alongside.
Table 8-1: CHP CAPEX
Scheme CHPs chosen Capital cost (total) Maintenance cost(£/operating hour perCHP) for 15-yearagreement
Cribbs 2 X J620 2 x £1,325,500=£2,651,000
£25.36
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New Earth N/A N/A N/A
Southmead 2 x J612 2 x £921,500 =£1,843,000
£17.99
UWE 2 X J616 2 x £1,090,000=£2,180,000
£21.22
8.4 ENERGY CENTRE SIZE
The area required by the energy centre is based upon previous designs carried out by WSP |Parsons Brinckerhoff. The estimated floor area required is set out in the table below:
Table 8-2: Energy centre estimated floor area
Network Estimated energy centre size (m2)
Cribbs 1120
New Earth Solutions N/A – it is assumed that any necessary plant (heatexchanger and pumps) will be housed within NewEarth Solutions
Southmead 840
UWE 750
It should be noted that these sizes are indicative and for costing only.
8.5 CONSUMER SIDE COSTS
The cost of domestic heat interface units and non-domestic heat substations are included withinthe capital cost of the different scheme options. A domestic HIU cost of £1200 per dwelling hasbeen used, based upon an average HIU cost. Commercial heat interface unit cost depends on theunit size, and is based upon quotes obtained from suppliers. These are summarised below, withfull details in an appendix to this document.
Table 8-3: Summary of consumer side costs
Network Total residentialproperties
HIU cost Number ofnon-domesticconnections
Overall CIU cost
Cribbs 2750 £3,300,000 12 £1,225,000
New Earth 0 N/A 27 £54,000
Southmead 0 N/A 8 £232,000
UWE 4240 £5,088,000 15 £409,000
7 One CIU for Accolade Wines, and assumed one CIU at the interface between New Earth Solutions and theDH network
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8.6 NEW DEVELOPMENT HEAT NETWORKS
The cost of the heat network on each new development site also needs to be taken into account.It is not within the scope of this work to design each new development plot network, and so thefollowing approximation has been used:
For each dwelling:
à 5m of DN 80 main spine at £500/m – total of £2500
à 3m of DN25 connection from main spine to dwelling at £350/m – total of £1050
à Final connection cost to HIU of £250
à Thus a total per dwelling cost of £3800. Note all costs are for soft dig.
It should be noted that this is a very high-level approach and detailed analysis will be required toestablish more accurate plot level costs. This is outside the scope of this commission, however.
8.7 OTHER CAPEX
The following additional items of capital expenditure are included:
Table 8-4: Other capex
Item Cost
Professional fees 12% of CAPEX (excludingpipework)
Contingency 20% of CAPEX (excludingpipework)
8.8 SUMMARY OF CAPEX
Summaries of capital expenditure for the four schemes are set out in the table below:
Table 8-5: Summary of CAPEX
Cribbs New Earth Southmead UWE
CHPengines
£2,651,000 N/A £1,843,000 £2,180,000
Thermalstorage
£150,000 N/A8 £100,000 £150,000
Utilityconnections
£195,000 £195,000 £195,000 £195,000
Energycentrebuilding
£1,848,000 N/A £1,386,000 £1,238,000
8 With a total heat output of 8MWth, the heat output from the plant is far greater than the demands ofAccolade Wines. As such, thermal storage is not required, as it is assumed that there will always be heatsupply when desired.
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Mechanicalprocess andcontrols
£1,875,000 £100,0009 £550,000 £2,396,00010
Transmission pipework
£8,450,000 £1,040,000 £5,117,000 £9,363,000
On site pipenetwork
£10,450,000
N/A N/A £16,112,000
HIU(domestic)
£3,300,000 N/A N/A £5,088,000
CIU(Commercial)
£1,225,000 £54,000 £232,000 £409,000
Professionalfees (at12%)
£1,349,000 £80,000 £517,000 £1,399,000
Contingency(20%)
£2,249,000 £70,000 £861,000 £2,331,000
TOTAL £33,742,000
£1,539,000 £10,801,000 £40,861,000
8.9 MAINTENANCE
The following items of plant and system maintenance are included:
Table 8-6: Maintenance costs
Plant item Unit Notes
Gas CHP p/kWhe From supplier quotes for a rangeof CHP engine sizes
M&E £/annum 1% of back up boiler CAPEX
DH pipework £/annum 1% of capital outlay following a 2-year warranty period.
8.10 REPLACEMENT COSTS (REPEX)
End of service life replacement costs are included within the modelling and are set out in the tablebelow. Pipework has a 45 to 50 year life, and so its replacement is not included within the scopeof this study.
9 To cover pumping and peripheries10 Based on a peak network demand of 47MW minus the peak demands of UWE at 6MW and MoD at
14.7MW
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Table 8-7: REPEX costs
Anticipated lifetime (years) Replacement cost aspercentage of CAPEX
Gas CHP unit 15 70%
Energy Centre Building 40 40%
Back up gas boilers 30 50%
Residential HIUs 15 75%
CIUs 25 75%
8.11 OPERATING INCOME
CONNECTION CHARGES
Connection charges are levied by ESCOs on new developments which connect to the network, asdevelopers are able to avoid the cost of installing boilers/ associated energy centre plant. Aconnection charge is only applicable to new developments (as there is no such saving for existingbuildings), i.e. the following:
à Cribbs Patchway New Neighbourhood (Cribbs network)
à Bristol Rovers/UWE stadium (UWE network)
à Harry Stoke (UWE network)
à Land East of Harry Stoke (UWE network)
à Land east of Coldharbour Lane (UWE network)
The following connection charges are used:
Residential £4000/dwelling
Non-residential £150/kWth
Whilst connection charges are not normally possible for existing buildings capital contributions inlieu of replacement of existing plant can often be included in final commercial agreements. Thepotential for these contributions would need to be examined on a case by case basis during futuremore detailed studies.
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8.12 CONSUMER UNIT MAINTENANCE, METERING AND BILLING COSTSItem Cost per annum
Domestic customers
Account management £85
Heat Trust £5
Bi Annual HIU maintenance £25
Total per annum £115
Commercial customers
Account management £400
Annual CIU inspection and maintenance £100
Total per annum £500
8.13 HEAT SALES PRICES
When obtaining heat supply from boilers, there are a number of elements which need to be takeninto account – i.e. the price of heat is more than the price of the gas which goes into the boiler.These elements are the following:
à Cost of gas, taking into account the efficiency of boilers which would have been required(under a gas boiler “base case” scenario) to generate heat.
à Gas supplier’s standing charge
à Boiler maintenance
à Boiler replacement
These elements are all taken into account when deriving the cost of heat sold to customers, sothis price is higher than gas cost.
The following heat sales prices are used, as within the Cribbs Patchway New NeighbourhoodHeat Network Feasibility Study11. Heat prices are indexed through time in line with gas cost as perDECC Quarterly Price Projections, November 2015 (Gas Services Rate, Central Scenario)
Table 8-8: Heat sales prices
Customer type Price (p/kWh)
New Residential 10.5
New Non-Residential 7
Existing Residential 10
Existing Non-Residential 5.6
11 Cribbs Patchway New Neighbourhood Heat Network Feasibility Study, WSP | Parsons Brinckerhoff,September 2015
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A lower sales price is assumed for Accolade Wines of 3.5p/kWh; this is because the site willretain its own gas boilers, with New Earth Solutions providing base load only.
8.14 ELECTRICITY SALES
The following electrical sales prices are used:
Price (p/kWh)Private Wire 10.5Grid Export 4.5
EMBEDDED GENERATION
Western Power Distribution (WPD) was contacted to assess whether potential energy centrelocations lie in network constrained areas. The general feeling was that the proposed locations donot currently lie in areas of excessive constraint; however levels of generation applications innorth Bristol have increased substantially over the last 1-2 years and therefore some level ofupstream reinforcement of the network is likely.
WPD can undertake a Budget Estimate, free of charge, which provides indicative costs for theconnection to an appropriate point on the network, and it is recommended that the local networkbe considered in future, more detailed, feasibility studies.
‘LICENCE LITE’
Licence Lite is a mechanism under which a higher value can be obtained for electricity by smallergenerators. Its implementation is currently being investigated in London, where the GLA recentlyissued an Invitation to Negotiate (ITN) to embedded generators, on their proposals for selling theGLA electricity for its ‘Licence Lite’ supplies. This information, once gathered will be assessed andmodelled and the stakeholders consulted for indication as to how the Licence Lite scheme willwork in practice.
There may be serious barriers to the procurement of privately generated electricity in this manner,but this will only become apparent once the market is tested both commercially and contractually.The current aim is to develop a scheme, and begin operations in spring 2016, after which thesituation will be more apparent, and the viability of such a scheme in the Avonmouth Severnsideregion can be investigated.
8.15 ELECTRICAL IMPORT AND GAS
Electrical and gas purchase prices are based on DECC price projections12. The following 2016base year prices are used:
Utility 2016 cost (p/kWh)
Gas (Services rate) 3.25
Electricity (Services rate) 11.25
12 https://www.gov.uk/government/collections/energy-and-emissions-projections
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8.16 PURCHASE OF HEAT FROM NEW EARTH SOLUTIONS
The price at which heat would be purchased from New Earth Solutions is not known. Thus in thisreport, analysis is carried out to establish the maximum price at which heat would need to bepurchased such that the scheme is viable.
It should be noted that heat will be recovered from the gasification process and not the steamturbine, and so the cost of heat only needs to reflect investment in the scheme and a small marginto make the scheme worthwhile to New Earth Solutions. A heat purchase price of 0.5p/kWh isassumed.
8.17 VARIATION THROUGH TIME
For the purposes of modelling, it has been assumed that construction occurs in 2019, withoperation in 2020. This approach can be adapted to a later start date, with the only change beinga minor variation in utility prices. All utilities prices are modelled as varying through time in linewith DECC price projections (central scenario), November 2015.
8.18 CRC AND OTHER CARBON TAXATION SCHEMES
It should be noted that the Treasury is currently undertaking a review into reforming the carbonreporting and taxation regime for UK businesses. A consultation, entitled Reforming the businessenergy efficiency tax landscape ran between September and November 2015. Whilst at the timeof writing the outcomes of this are not known, there may well be changes to the carbon taxregimes, including CRC, over the next few years. As such, representing carbon taxation andincentives within modelling is outside the scope of this report. However, a DH scheme will resultin savings for loads connecting to the network from this perspective.
8.19 RHI
The supply of heat from New Earth Solutions is able to profit from RHI. It is not certain at thisstage what level of RHI could be generated - RHI for heat from combustion of municipal solidwaste biomass is worth 2.03p/kWh per kWh of heat from the renewable fraction of waste;assuming a deemed 50% biogenic fraction of that waste gives a RHI of around 1p/kWh. Biogenicfractions for the NES plant could be higher than this as there is significant pre-sorting of waste.
If the plant were to become CHPQA accredited then the RHI tariff could be as high as 4.17p/kWh– again assuming a 50% biogenic fraction would give an RHI value of around 2.1p/kWh of heatsupplied.
For the purposes of modelling, we assume a RHI value of 2p per kWh.
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9 FINANCIAL RESULTSThis section sets out the financial outputs of the modelling. Results are presented as discountedcumulative cashflows over a 25 year time period, at a discount rate of 12%. This is also presentedas a net present value (NPV) at the same discount rate.
9.1 CRIBBS
The discounted cumulative cashflow graph for the Cribbs Patchway network, together with the 25-year NPV at a 12% discount rate, is set out below:
Figure 9-1: 25-year cumulative discounted cashflow, Cribbs Patchway
25-year NPV, 12% discount rate 25-year NPV, 6% discount rate
2 x JMS JMS 620 £5,499,000 £19,046,000
9.2 NEW EARTH SOLUTIONSThe discounted cumulative cashflow graph for the New Earth Solutions-Accolade Wines link,together with the 25-year NPV at a 12% discount rate, is set out below
-£20,000,000
-£15,000,000
-£10,000,000
-£5,000,000
£0
£5,000,000
£10,000,000
2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050
Year
Discounted Cumulative Cashflow (£)
2 x JMS JMS 620
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Figure 9-2: 25-year cumulative discounted cashflow, New Earth Solutions
25-year NPV, 12% discount rate 25-year NPV, 6% discount rate
New Earth Solutions £144,000 £1,235,000
9.3 SOUTHMEAD
The discounted cumulative cash flow graph for the Southmead network, together with the 25-yearNPV at a 12% discount rate, is set out below:
Figure 9-3: 25-year cumulative discounted cashflow, Southmead
25-year NPV, 12% discount rate 25-year NPV, 6% discount rate
2 x J612 -£2,738,000 £2,316,000
-£1,800,000
-£1,600,000
-£1,400,000
-£1,200,000
-£1,000,000
-£800,000
-£600,000
-£400,000
-£200,000
£0
£200,000
£400,000
20192020202120222023202420252026202720282029203020312032203320342035203620372038203920402041204220432044204520462047204820492050
Year
Discounted Cumulative Cashflow (£)
New Earth Solutions
-£12,000,000
-£10,000,000
-£8,000,000
-£6,000,000
-£4,000,000
-£2,000,000
£02019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050
Year
Discounted Cumulative Cashflow (£)
2 x J612
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9.4 UWEFigure 9-4: 25-year cumulative discounted cashflow, UWE
25-year NPV, 12% discount rate 25-year NPV, 6% discount rate
2 x J616 -£2,276,000 £10,375,000
-£25,000,000
-£20,000,000
-£15,000,000
-£10,000,000
-£5,000,000
£02019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050
Year
Discounted Cumulative Cashflow (£)
2 x J616
-£14,000,000
-£12,000,000
-£10,000,000
-£8,000,000
-£6,000,000
-£4,000,000
-£2,000,000
£0
£2,000,000
£4,000,000
2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050
Year
Discounted Cumulative Cashflow (£)
2 x J616
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10 SENSITIVITY TO KEY LOADS – UWENETWORK
10.1 INTRODUCTION – LINEAR HEAT DENSITY MODELLING
The effect of reducing the number of connected loads– i.e. increasing the linear heat density ofthe pipe route was carried out for the UWE network, in order to seek to improve the financialviability of this scheme.
In order to examine the best loads to form a “core” network, WSP | Parsons Brinckerhoffassessed the heat loads using our bespoke linear heat density model.
This model is based around the understanding that commercial viability is a product of therelationship between the length of pipework and the connected load for a potential heat network. .Essentially it is quantifying the balance between income (linked to heat sales volumes) that couldbe generated through connection to a load, against an indicator of the cost to make thatconnection (network length).
The model developed by PB is innovative in that it generates a progression of loads that could beconnected. This means that starting from an anchor customer, the model looks at the additionallength of network required to connect to each of the other loads on the scheme, and the resultinglinear heat density (i.e. demand divided by length of connection) of the marginal addition of each.The most ‘linear-heat-dense’ connection is selected, and then the process begins again. Thisiterative approach delivers a ranked order of likely connection viability for the identified potentialloads on the scheme.
10.2 LINEAR HEAT DENSITY RESULTS
The following graph shows the progressive linear heat density of the overall network withincreasing numbers of load points connected:
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Figure 10-1 Linear heat density results
This graph should be interpreted in conjunction with the following list of demands points / loadsthat correspond to the addition of load to the network read from left to right on the graphabove, i.e. MoD Filton Abbey Wood represents the leftmost point on the graphic:
Table 10-1 Linear heat density testing (list)
1 MoD Filton Abbey Wood
2 Bristol Rovers/ UWE stadium
3 Hewlett Packard
4 Land East of Harry Stoke
5 Harry Stoke
6 Holiday Inn Bristol-Filton
7 Land East of Coldharbour Lane
8 Higher Education Funding Council
9 Frenchay Hospital
10 Romney House
The graph should be considered cumulatively – i.e. the first point represents the heat density of anetwork supplying solely MoD Abbey Wood, the second a network supplying MoD Abbey woodand Bristol Rovers/UWE stadium.
It can be seen that the highest heat density is achieved by including the first five loads (plus UWE,at which the energy centre is modelled as located). It is this network which is analysed in thesubsequent sections:
-
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0 5,000,000 10,000,000 15,000,000 20,000,000 25,000,000 30,000,000 35,000,000 40,000,000 45,000,000 50,000,000
Overall network LHD (MWh p.a. / m) vs load (kW p.a.)
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10.3 LOAD PROFILING
The hourly profile for the core UWE network load is illustrated in the image below:
Figure 10-2: Core UWE network profile through the year
The annual heat demand for this network is 41.5GWh/annum (note that this higher than in theLHD graph because of the inclusion of UWE).
10.4 PIPELINE MODELLINGTable 10-2: UWE core network pipeline modelling outputs
Network option Network cost Total trenchlength (m)
Total peak load atenergy centre(MWth)
Pumppower(kWe)
Annual heatlosses(MWh/annum)
Core UWE £4,453,000 4299 37.5 260 1370
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
123
246
369
492
511
5613
8716
1818
4920
8023
1125
4227
7330
0432
3534
6636
9739
2841
5943
9046
2148
5250
8353
1455
4557
7660
0762
3864
6967
0069
3171
6273
9376
2478
5580
8683
1785
48
Hea
tdem
and
(kW
)
Hour through year
Core UWE Network
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Figure 10-3: Core UWE network
Table 10-3: UWE core network modelling pipe lengths and cost
Diameters(nominal) (mm ID)
Cost per m(trench) (£
capex)
Length of this diameter in thisoption (m)
Total cost for pipediameter (£)
125 £979 57 £55,902150 £1,099 142 £156,540200 £1,232 1,818 £2,239,428250 £1,380 1,814 £2,502,772300 £1,430 467 £667,441
10.5 CHP MODELLING
There is little difference between the annual heat demands of the full and core UWE networks,and as such the same CHP sizes are modelled.
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10.6 FINANCIAL INPUTS
The following financial inputs were used within the modelling for the core UWE network:
Table 10-4: Core UWE network CHP CAPEX
Scheme CHPs chosen Capital cost (total) Maintenance cost(£/operating hour perCHP) for 15-yearagreement
Core UWE 2 X J616 2 x £1,090,000=£2,180,000
£21.22
10.7 ENERGY CENTRE SIZETable 10-5: Core UWE network energy centre estimated floor area
Network Estimated energy centre size (m2)
UWE 700
10.8 CONSUMER SIDE COSTSTable 10-6: Core UWE network consumer site costs
Network Total residentialproperties
HIU cost Number ofnon-domesticconnections
Overall CIU cost
Core UWE 3200 £3,840,000 12 £335,000
10.9 SUMMARY OF CAPEXTable 10-7: Summary of CAPEX
Core UWE
CHP engines £2,180,000
Thermal storage £150,000
Utility connections £195,000
Energy centre building £1,155,000
Mechanical process and controls £1,512,00013
Transmission pipework £5,622,000
New development distribution pipework £12,160,000
HIU (domestic) £3,840,000
CIU (Commercial) £335,000
Professional fees (at 12%) £1,124,000
Contingency (20%) £1,873,000
TOTAL £30,146,000
13 Based on a peak network demand of 37.5MW minus the peak demands of UWE at 6MW and MoD at14.7MW
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10.10 FINANCIAL RESULTSFigure 10-4: Discounted cumulative cashflow – core UWE scheme
25 year NPV at 12% discountrate 25 year NPV at 6% discount rate
2 x J616 -£843,000 £8,809,000
These results can be compared to the full UWE cluster:
Table 10-8: Financial comparison of UWE network options
25-year NPV, 12% discount rate 25-year NPV, 6% discount rate
Full UWE Cluster -£2,276,000 £10,375,000
Core UWE Cluster -£843,000 £8,809,000
-£18,000,000
-£16,000,000
-£14,000,000
-£12,000,000
-£10,000,000
-£8,000,000
-£6,000,000
-£4,000,000
-£2,000,000
£02019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050
Year
Discounted Cumulative Cashflow (£)
2 x J616
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11 SOUTHMEAD NETWORK – FURTHERANALYSISThe Southmead network is the most poorly performing of the schemes, and so it was proposedthat further analysis, as for the UWE cluster, be carried out to establish whether a configurationexists which is financially viable. The linear heat density graph is provided in the figure below:
11-1: Southmead network linear heat density
As with the UWE network, this graph should be read in conjunction with the table below, from leftto right, i.e. Horfield Leisure Centre represents the leftmost point on the graph.
1 Horfield Leisure Centre
2 South Gloucestershire & Stroud College
3 Filton Sports & Leisure Centre
4 Charborough Road Primary School
5 Badocks Wood Primary - Southmead Children’s Centre
It can be seen that the linear heat density is extremely low for any combination of loads (compareLHDs for this scheme to those for the UWE network) and as such there does not exist a “core”network which would have a greater likelihood of viability than the full selection of loads.
It is noted that the one element that could radically alter the potential for this scheme would be theinclusion of loads at Airbus and related industries around Filton. As indicated in earlier sectionsthe site has advised that there would need to be significant investment in on site systems to
1.0
1.0
1.1
1.1
1.2
1.2
1.3
0 1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000
Overall network LHD (MWh p.a. / m) vs load (kW p.a.)
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convert these to use LTHW. Such an assessment is beyond the scope of this study but furtherinvestigation to consider the potential benefits should be considered. This could allow for a futurenetwork based around the Airbus site with significant electrical as well as heat loads generatingincome for the scheme.
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12 FINANCIAL SENSITIVITYA sensitivity analysis was carried out to establish the effect of varying the following items:
à Primary energy costs
à Energy sales prices
à Project lifetime
à Discount rate
à RHI (or other incentive) support levels.
12.1 ENERGY COSTS / PRICES
This section examines the results of varying the DECC price projection scenario, showing theeffect of high and low gas and electricity prices as compared to the reference scenario which hasbeen used within the main body of the report. Heat sales prices are indexed against gas purchaseprice, and so the variation in cost through the years is reflected here as well.
Network 25-year NPV with DECCReference Scenario
25-year NPV with DECCLow Scenario
25-year NPV with DECCHigh Scenario
NPV – 12% NPV -6% NPV – 12% NPV – 6% NPV -12% NPV – 6%
Cribbs £5,499,000 £19,046,000 £4,879,000 £18,816,000 £4,170,000 £16,357,000
New Earth £144,000 £1,235,000 -£254,000 £596,000 £608,000 £2,007,000
Southmead -£2,738,000 £2,316,000 -£2,375,000 £3,367,000 -£4,552,000 -£1,079,000
UWE -£2,276,000 £10,375,000 -£3,116,000 £9,794,000 -£3,281,000 £8,270,000
Again, the different price scenarios do not have too great an impact on the schemes’ financialperformances.
12.2 EFFECT OF RHI
This section shows the effect of removing RHI from the New Earth network:
Network 25-year NPV including RHI 25-year NPV excluding RHI
NPV – 12% NPV -6% NPV – 12% NPV – 6%
New Earth £144,000 £1,235,000 -£503,000 £181,000
It can be seen that reducing RHI from 2p/kWh of heat supplied from New Earth Solutions to0p/kWh has a fairly significant impact on the financial viability of the scheme, and will require anincreased heat sales price in order to make up this shortfall.
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13 CARBON SAVINGSResults are presented as carbon savings over a gas boiler base case. It should be noted thatthere is a difference in the way that carbon is measured for CRC monitoring purposes and underthe DEFRA reporting methodology. The differences are set out below:
à CRC: CRC is charged on the carbon associated with gas used in top-up boilers and the fullsite electrical consumption. Gas used in CHPs is not included.
à DEFRA: Overall carbon is the sum of carbon associated with gas and electrical import.Electricity sold to the grid is treated as “carbon negative” – i.e. it reduces the overall carbonsum.
Table 13-1: Anticipated carbon savings
Scheme Overall carbon generated perannum (tonnes/yr)
Carbon savings over gas boilerbase case per annum(tonnes/yr)
Cribbs 3,576 9,303
Accolade Wines 0 1,026
Southmead 1,697 7,035
UWE 4,377 8,650
Core UWE network 2,553 7,817
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14 CONCLUSIONSThis report examined the development of heat networks in four clusters:
à Cribbs Patchway
à New Earth Solutions to Accolade Wines
à Southmead
à UWE
The Cribbs Patchway network performs well financially, with a payback period of around eightyears under a 12% discount rate and is also able to achieve significant carbon savings of around9300 tonnes per annum over a gas boiler base case. The UWE cluster is also a strong performer,paying back in around seventeen years, and a “core” UWE network would also perform well,paying back in around fourteen years.
A link between New Earth Solutions and Accolade Wines has a funding gap which would need tobe met in order for the scheme to break even, even at a very low heat purchase price from NewEarth Solutions. The exact nature of the heat demand at Accolade Wines should also beconfirmed, to ensure that the supply from New Earth Solutions is appropriate (it is understood thatthe clean in place demand is provided, in part, from recovered hot water from the onsitecompressor cooling system, and only top-up heat required).
The Southmead network performs less well; this is largely because it is unable to recoup much ofthe initial outlay through connection fees, as is the case with the Cribbs Patchway and UWEnetworks. However, when considering a wider Avonmouth-Severnside network, it can be seenthat this network occurs in between the Cribbs Patchway and UWE clusters. It may well be worthconnecting up some of the loads which occur close to this main trunk route, although it is notrecommended that the network be extended to Badcock’s Wood Primary, Southmead Hospital orHorfield Leisure Centre. Further consideration should also be given to the potential for alterationsat Airbus to enable connections as this would radically impact on the economics of any scheme inthis area. Additional work should also be carried out to establish the costs and design of heatnetworks on the new developments, namely Cribbs Patchway, the Frenchay Hospital site, LandEast of Coldharbour Lane, Land East of Harry Stoke and Harry Stoke.
It should be noted that all schemes have been modelled with electricity generated being sold tothe grid. This should be considered as the most conservative scenario, with the possibility of ahigher price possible through sale via a private wire network or under Licence Lite scenarios.However, it should be borne in mine that the CHPs are interim heat sources pending a wider heatnetwork being developed and connection to other low carbon heat sources. As such, any privatewire network could only be a temporary solution, and could well overstate the financialperformance of the schemes examined.
Finally, as mentioned within the report, regulation around carbon taxation and incentives is likelyto change, and should this come into place, consideration should be given as to how this has thepotential to improve or decrease the financial viability of the DH schemes examined.
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15 STRATEGIC NETWORK ASSESSMENT15.1 INTRODUCTION
The prospect of large scale heat sources in the Avonmouth and Severnside area to serve heatdemands across a wide area is exciting and potentially transformative for energy supply in thearea. Large scale sources of waste heat are routinely used on the continent to supply large urbanareas, with key examples being in Copenhagen, Rotterdam and Helsinki. The supply of heat fromEnergy from Waste plants would not be unique in the UK, Sheffield and Nottingham have hadsystems in place for many years, and more recently Coventry has taken the first steps indeveloping a network through a relatively small connection from their EfW plant to councilbuildings.
The common factor in all of these schemes has been significant input from the local authority inproviding or underwriting investment in what amounts to very large scale infrastructure. Therehas also been a very key role for the local authorities in helping with town planning, land issuesand the crossing of major infrastructure.
In order to understand the value of investing time and resources in the development of such ascheme South Gloucestershire has asked for an initial high level assessment of the potentialbenefits. This section sets out the methodology used by WSP | Parsons Brinckerhoff inundertaking this high level assessment and the results of the assessment.
15.2 METHODOLOGYWSP | Parsons Brinckerhoff has utilised the following approach to this high level assessment:
1. Assess the potential scale and costs of heat supply2. Identify potential major heat loads and routes to connect these3. Establish a high level estimate of capital costs of connection to major load centres4. Assess the potential level of heat supply that could be provided by the network5. Assess the potential value of this heat supply6. Assess the potential return on investment and carbon savings that could result7. Identify key risks to the delivery and tasks for a next stage assessment
15.3 HEAT SUPPLY – CAPACITY AND COSTS
HEAT SUPPLY CAPACITYA range of heat sources has been identified, with the main immediate opportunities being:
Company Size Fuel Technology Status Heat Potential
SITA -SERC 32MWe
MunicipalWaste
Mass Burn withSteam Turbine
In construction dueoperational in 2016.
20MWth (potential toincrease at increasedcost)
Balfour BeattyInvestments &Nexterra
11MWe Biomass Pyrolysis with
Steam Turbine
Financing-expectedoperational late2017.
up to 8MW.
New EarthSolutions –Avonmouth A
8MWe
RefuseDerivedFuel
Pyrolysis andGasificationfeeding a steamturbine generator
Operational Estimated up to 8MW
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It is noted that the New Earth Solutions (NES) plant would initially supply its heat to AccoladeWines and potentially other users in the surrounding development area. Given the large potentialheat demands around the site, and its location at some distance from the other two majorpotential supplies, it is not expected that this plant would contribute initially to a strategic network.
Should other supplies in the area - NES Avonmouth B and Cylamax for example – come online,then a further network from the Avonmouth area or connection to the Severnside strategicnetwork could be considered in the future. The NES ‘B’ plant is not however considered further inthis initial assessment.
Another potential very large source of heat was also identified adjacent to the SITA SERC plant.
Scottish andSouthernEnergy –Seabank 1&2
1,140MWe Gas Combined cycle
gas turbine
Seabank 1 startedoperations in 1996 andSeabank 2 in 2001. Theplants are less efficientthan the proposed CCGTstations which may bebuilt. As of 2011 they nolonger operate as baseload generation butinstead are operatingintermittently.
Due to theiroperational status thepotential for a steadysupply of heat suitablefor district heating islow.
As indicated this plant does not operate reliably but as its operation is likely to be in peakelectrical demand periods – typically in winter – it may be possible to utilise heat from this sourceinto a large scale network to add to peak supply capacity. This source is not considered as abase case for the Severnside strategic network but could be assessed at the next stage in termsof future potential expansions.
The overall scale of heat supply to the strategic network is therefore taken to be some 28MWthfor the base case. This scale of supply is relatively small if considered in the context of peakdemands for the area but would be considered large for a base load CHP type supply. Typically abase load supply such as a CHP plant will serve loads with peaks up to 10 times the base loadcapacity but with good design and use of thermal storage can supply 60-70% of the annual heatdemands for these loads. It could conservatively be considered that, operating as base load aSevernside strategic network could serve over 200MWth of peak load with the majority of theannual heat supply.
HEAT SUPPLY COSTSBoth the main potential heat supply sources would be derived from steam extraction from steamturbines. Such extraction has an impact on the electrical output of the turbine and as such thereis a cost of heat production to cover the loss of revenue associated with the lost electricityproduction. The ratio of heat output to loss of electrical output is termed the Z factor and variesdepending on the specifics of the steam turbine system design.
Both of the main potential heat supply sources should also be eligible for incentive paymentsunder the Renewable Heat Incentive (RHI) programme. For the SERC plant RHI would bepayable on the biogenic content of the heat delivered to buildings connected to the heat network(i.e. not including heat losses). For municipal solid waste, the biogenic content is typicallyassumed to be 50 percent of the fuel.
It is noted that the RHI rates payable for the two main heat sources would be different. ForEnergy from Waste the applicable RHI rate is that for ‘large biomass’ plants. For the Nexterrabiomass scheme there is a specific biomass CHP tariff available.
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The table below set out the key assumptions that go into an assessment of the cost of heatextracted from each plant.
Project Name SERC Nexterra NotesHeat Capacity 20 8 MWSupply Type Steam
Turbineextract
SteamTurbineextract
Incentive Mechanism RHI RHIEligible Y YHeat supply Z factor 5 5 May vary with level of heat
extractedValue of electrical output £50.00 £96.00 /MWh Nexterra value includes ROC
buy out priceValue of Incentive £22.40 £41.00 /MWhProportion of outputeligible 50% 100%
Adjustment for losses85% 85%
Assume losses only intransmission main to clusterenergy centres
Cost of Heat – beforeincentive £10.00 £19.20 /MWh
Value of incentive £9.52 £34.85 /MWh
Cost of heat net ofincentive £0.48 (£15.65) /MWh Note Nexterra cost of heat is
negativeAssumed cost of heat toinclude pump costs andmargin for generator £5 £1 /MWh
Margin includes formanagement and operationalcosts related to heat offtake andact as an incentive to maximiseheat offtake.
We note that the cost of heat to the network operator from Nexterra has been assumed to bepositive in spite of the larger margin that this creates as compared with the cost of heat fromSERC. This assumption has been made at this early stage in development to recognise thefollowing additional costs and risks related to the Nexterra plant:
1. The Nexterra plant is assumed to bring the heat to a connection point adjacent to theSERC plant thus incurring additional costs.
2. There are significant risks related to the RHI scheme for this type of plant and thesewould need to be recognised in the heat offtake arrangement
3. The operational costs for eg pumping and losses for the Nexterra plant are higher than forthe SERC plant due to its location
The actual arrangements for heat offtake should be explored with both operators at the nextstage.
15.4 HEAT LOADS AND NETWORK ROUTE
HEAT LOADSThis initial high level assessment assumes that the cluster energy demands identified earlier inthis report can be supplied via a transmission main connection to a single “Energy Centre” foreach cluster rather than being formed of individual connections to end users. This obviouslyassumes that the clusters have already been developed at least to some extent and the finalarrangements may be different. This assumption does allow for a simple initial test of both the
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level of cluster development that may allow for the scheme to be viable and also of sensitivity ofthe scheme to single large connections (eg MOD Abbey Wood or Cribbs Patchway NewNeighbourhood).
The heat loads considered in this assessment have been updated based on the loads identified inthe earlier sections of this report and are replicated in the following tables for convenience:
Cribbs Patchway (EC at CPNN) Heat demand(MWh/annum)
804 CPNN 35,47287 Rolls Royce 7,00092 Patchway Locality Hub 20093 Callicroft Primary School 18565 Patchway Community School 1,00078 St Chad's Primary School 12058 Aztec Hotel & Spa 3,63049 Hilton Bristol Hotel 3,27490 Holy Family Primary School 14086 Stoke Lodge Primary School 200Totals (Base Loads) 51,221Implied peak (11% Load Factor) 53 MWPotential additional Loads Demand (MWh)45 Cavendish Nuclear 271114 Charlton Hayes 9,063Totals (Potential Additional Loads) 9,334
Southmead (EC at Southmead)ID Name (Base Loads) Demand (MWh)360 Southmead Hospital 28,508385 Horfield Leisure Centre 1,518210 Charborough Rd Primary School 170215 Filton Sports & Leisure Centre 634156 S Glos & Stroud College 3,150346 Badocks Wood Primary 120Totals (Base Loads) 34,101Implied peak (13% load factor) 30 MWPotential additional Loads Demand (MWh)172 GKN Aerospace 179170 Airbus 22,752Totals (Potential Additional Loads) 22,931
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UWE (Energy Centre at UWE)ID Name (Base Loads) Demand (MWh)157 Land East of Harry Stoke 11,986188 Harry Stoke 7,245302 Hewlett Packard 1,523308 UWE 6,768274 MoD Filton Abbey Wood 8,993332 Higher Education Funding Council 432343 Bristol Rovers / UWE stadium 4,980359 Land East of Coldharbour Lane 2,818383 Romney House 289350 Frenchay Hospital 2,936245 Holiday Inn Bristol-Filton 3,300Totals 51,270Implied peak (13% Load Factor) 49 MW
In summary the total available loads are:CPNN Southmead UWE Total
Base load (MWh/annum) 51,221 34,101 51,270 136,592Implied peak for Base (MW) 53 30 49 132Potential additional loads(MWh/annum)
9,334 22,931 - 32,265Overall total potential(MWh/annum) 60,554 57,032 51,270 168,857
As agreed at the priority sites workshop the Emersons Green cluster has not been included in thisassessment. Once the network had reached UWE a decision would need to be taken onwhether to progress to Emersons Green or perhaps continue to develop towards Bristol CityCentre where a much denser set of loads would be available. This decision would however bepredicated on the network having reached as far as UWE and sufficient heat supply remaining tojustify further expansion.
The decision was therefore taken at this stage to undertake the study based on the CribbsPatchway, Southmead and UWE clusters identified. An assessment of the potential viability of aconnection from UWE/MOD to the proposed new Temple and Redcliffe schemes energy centre atSt Phillips has also been undertaken.
NETWORK ROUTE
The network route, and hence lengths of pipework required, has been developed as described inthe Heat Mapping Report. Should the scheme prove viable on this initial assessment then theproposed routes will be investigated in more detail to assess technical viability, level of risk andpotential alternatives, including two route options which extend down from the UWE cluster to theBristol City Centre at St Philips Marsh, where an energy centre is proposed on the site of the oldGreat Western Refuse Transfer Station, taking into account the social housing blocks which lie tothe North of St. Philips. The route is generally as shown in Figure 15-1 below. The 2 routeoptions which extend to the City Centre are shown in Figure 15-2.
The two routes which link up the North Fringe with Bristol City have been selected to run betweenthe most promising cluster in this study; UWE and the city centre via paths which avoid majorconstraints, crossing major infrastructure at the least disruptive locations; minor roads anddisused railway lines turned into cycle paths have been used in preference to major roads tominimise disruption and cost of the installation.
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The M32 represents a significant physical barrier which needs to be crossed to arrive at StPhilips, this is most easily executed in two locations; the roundabout which runs under theOverpass adjacent to Eastville Park, and the cycle path adjacent to the roundabout over theunderpass at St Pauls, where the M32 ends.
Figure 15-1: SERC to All Clusters
The pipe lengths for the main elements of the route are shown in the table below:
Connections Trench length (m)SERC to CPNN EC (load 804) 7,200CPNN EC (804) to Southmead EC (360) 7,678Southmead EC (360) to UWE (308) 4,310UWE to City Centre 7,450
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Figure 15-2: Route from UWE Cluster to the City Centre (Temple & Redcliffe EC in St Philips)
15.5 CAPITAL COST ESTIMATES
CAPITAL COST ELEMENTS
The capital costs for the network are made up of the following key elements:
à Heat extraction and distribution equipment at the heat source
à Pipework and installation (trenching, welding fittings etc.)
à Major infrastructure crossings – e.g. motorways, railways and waterways
à Interface equipment at each heat demand connection
à Project Costs including design, project management and contractor costs
à Contingencies
NETWORK DESIGN ASSUMPTIONS
A key element in assessing these costs is the assumptions around the way in which the pipenetwork would be designed and operated. For the purposes of this assessment the followingassumptions have been made.
à The network will operate as a transmission main with variable flow and temperature and willbe hydraulically isolated from connections at consumers
à The network will be designed to operate at higher temperature and pressures to minimise thepipe sizes and heat losses that will result
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à The operating temperatures at maximum demands will be
§ Flow: 110°C
§ Return: 70°C
Note – ideally return temperatures on the primary network will be closer to 50°C for newdevelopments, based on internal building system designs for 40°C returns and the local(secondary) network achieving 45°C, As there are a significant number of existing buildingshowever, a higher temperature will be allowed for initially. It should be expected that tariffs forconnection will incentivise lower return temperatures and that the Network Operator would workwith customers to reduce temperatures through modernisation of internal systems over time.
à The pipe size will be designed to achieve pressure drops around 100 Pa/m as per DistrictHeating Manual for London guide lines for main pipes
à The overall design pressure for the network (including pumping losses, static head and staticmargins) will not exceed 16bar (1.6MPa).
Based on these design criteria the transmission network has been modelled initially at 350mmnominal diameter pre-insulated district heating pipe allowing supply of up to 35MWth of heat(28MW from the two heat suppliers plus 7MWth for central thermal storage).
HEAT SUPPLY INTERFACES
The interfaces will incorporate:
à Steam pipework and control valve connection to the steam turbine
à Steam to hot water heat exchangers and condensate recovery connections
à District heating system controls and power supplies
à District heating system pumps and water treatment equipment
à Thermal stores
à Pipework and valving to the boundary of the site
à Associated civil and builders works
The costs for these systems are based on previous projects of a similar scale based on the worksbeing instructed and managed by the heat supplier. No additional project costs are thereforeincluded on top of these costs.
PIPEWORK AND INSTALLATION
Costs for pipework are taken from recent quotes for major pipework systems for “hard dig” (i.e.under roads) in London. They allow for contractors detailed design, prelims and trafficmanagement and can also be seen to include a London weighting. We note that some keyelements of pipework installation could be in soft dig areas and also that traffic managementalong most of the route would not be as significant as would normally be required in London.
The costing strategy provides a robust high end estimate of network costs to allow the potentialfor viable development to be tested – i.e. the basis of a decision about whether to proceed to amore considered assessment, or not. We have used a fully risked price which allows for dealingwith unknowns.
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Based on our experience of the price differentials, and the design and prelims elements includedin the costs quoted, we propose not to apply additional project costs and to apply a lower rate ofcontingency for this element.
MAJOR INFRASTRUCTURE CROSSINGS
We have not undertaken a detailed assessment of the requirements or opportunities for specificinfrastructure crossings at this stage. We have identified the following major infrastructurecrossings and made assumptions about the type of crossing that may be required.
à M49 at Farm Lane – assume pipe jack under motorway
à M5 at Hollywood Lane - assume trenched in road under motorway – no extra cost
à A4018 Double Carriage way at Hollywood Lane – assume trench with significant trafficmanagement
à Avonmouth railway at BAE Filton – assume pipe bridge adjacent to existing road bridge
à Railway at MOD – assume pipe bridge adjacent to existing road bridge
Cost estimates are based on recent quotations for pipe bridges, thrust bored and pipe jackinginstallations to cross a combination of rail, road and river infrastructure.
HEAT INTERFACES AT LOAD CONNECTION POINT
As noted above we have currently assumed a single connection at each cluster “Energy Centre”.This interface would comprise 100% dual heat exchange substations including controls, powersupplies etc. We have assumed that this substation installation could be installed within anexisting structure and connected alongside existing heat supply systems without majormodifications.
PROJECT COSTS
At this stage we have included high level estimates of costs for route surveying, design,specification , procurement, contractor prelims, overhead and profits (except where noted above)and contingencies reflective of the low level of certainty that can be achieved at this early stage.
COST ESTIMATES
In order to allow testing of a number of variations, the capital cost estimates have been brokenout into elements related to specific sections of the system. Total costs for a variety of optionsare presented as follows:
à Scenario 1 - All clusters – SERC and Nexterra supplies
à Scenario 2 - All clusters – SERC only (Note all base loads identified could be supplied bySERC)
à Scenario 3 - CPNN and Southmead only – SERC only
à Scenario 4 - CPNN only – SERC only
à Scenario 5 – Link from UWE to City Centre – NB this assessment is based on the assumptionthat the network has already reached UWE and only considers the additional network costs toextend to the City Centre
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Table 15-1: Capital Costs Scenario 1 All Clusters - SERC and NESItem Cost
estimate(£k)
Notes
Heat extraction and distributionequipment at the heat source
3,050 £1,650 at SERC£1,000k at NexterraPlus 800m3 thermal store £400k
Pipework and installation(trenching, welding fittings etc)
27,827 350mm pipework incl trench, install, make good,design and prelims - £1700/m trench
SERC to Cribbs EC – 7,200mCribbs EC to Southmead EC – 7,680mSouthmead EC to UWE – 4310m
Major infrastructure crossings– eg motorways, railways andwaterways
1,250 M49 at Farm Lane – £750kM5 at Hollywood Lane - no extra costA4018 Double Carriage way at Hollywood Lane– £100kAvonmouth railway at BAE Filton – assume pipebridge adjacent to existing road bridge - £200kRailway at MOD – assume pipe bridge adjacentto existing road bridge £200k
Interface equipment at eachheat demand connection
270 3 connections at £90k per connection
Project Costs including design,project management andcontractor costs
1,004 Next stages development including PM survey,design, specification and procurement (no legalor financial advice included) - £400kOwners Engineer and PM post procurement -£300k20% Contractor Prelims OH &P (except supplyinterface and pipework)
Contingencies 505 20% (except supply interface and pipework)Totals 33,906
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Table 15-2: Capital Costs - Scenario 2 All Clusters - SERC onlyItem Cost
estimate(£k)
Notes
Heat extraction anddistribution equipment at theheat source
2,050 £1,650k at SERC Plus 800m3 thermal store @ £400k
Pipework and installation(trenching, welding fittingsetc)
27,827 350mm pipework incl trench, install, make good,design and prelims - £1700/m trench300mm pipework incl trench, install, make good,design and prelims - £1300/m trenchSERC to Cribbs EC – 7,200mCribbs EC to Southmead EC – 7,680mSouthmead EC to UWE - 4310m
Major infrastructure crossings– eg motorways, railways andwaterways
1,250 M49 at Farm Lane – £750kM5 at Hollywood Lane - no extra costA4018 Double Carriage way at Hollywood Lane –£100kAvonmouth railway at BAE Filton – assume pipebridge adjacent to existing road bridge 200kRailway at MOD – assume pipe bridge adjacent toexisting road bridge £200k
Interface equipment at eachheat demand connection
270 3 connections at £90k per connection
Project Costs includingdesign, project managementand contractor costs
1,004 Next stages development including PM survey,design, specification and procurement (no legal orfinancial advice included) - £400kOwners Engineer and PM post procurement - £300k
20% Contractor Prelims OH &P (except supplyinterface and pipework)
Contingencies 505 20% (except supply interface and pipework)Totals 32,906
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Table 15-3: Scenario 3 – Capital Costs CPNN and Southmead only - SERC onlyItem Cost
estimate(£k)
Notes
Heat extraction anddistribution equipment atthe heat source
2,050 £1,650k at SERC Plus 800m3 themal store @ £400k
Pipework andinstallation (trenching,welding fittings etc)
£22,224
350mm pipework incl trench, install, make good,design and prelims - £1700/m trench300mm pipework incl trench, install, make good,design and prelims - £1300/m trenchSERC to Cribbs EC – 7,200mCribbs EC to Southmead EC – 7,680m
Major infrastructurecrossings – egmotorways, railwaysand waterways
1,050 M49 at Farm Lane – £750kM5 at Hollywood Lane - no extra costA4018 Double Carriage way at Hollywood Lane –£100kAvonmouth railway at BAE Filton – assume pipebridge adjacent to existing road bridge 200k
Interface equipment ateach heat demandconnection
180 2 connections at £90k per connection
Project Costs includingdesign, projectmanagement andcontractor costs
946 Next stages development including PM survey,design, specification and procurement (no legal orfinancial advice included) - £400kOwners Engineer and PM post procurement - £300k
20% Contractor Prelims OH &P (except supplyinterface and pipework)
Contingencies 435 20% (except supply interface and pipework)Totals 26,885
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Table 15-4: Capital Costs - Scenario 4 - CPNN only - SERC onlyItem Cost
estimate(£k)
Notes
Heat extraction anddistribution equipment at theheat source
2,050 £1,650k at SERC
Plus 800m3 themal store £400kPipework and installation(trenching, welding fittingsetc)
£12,240
350mm pipework incl trench, install, makegood, design and prelims - £1700/m trench300mm pipework incl trench, install, makegood, design and prelims - £1300/m trenchSERC to Cribbs EC – 7,200m
Major infrastructure crossings– eg motorways, railways andwaterways
850 M49 at Farm Lane – £750kM5 at Hollywood Lane - no extra costA4018 Double Carriage way at HollywoodLane – £100k
Interface equipment at eachheat demand connection
90 1 connections at £90k per connection
Project Costs includingdesign, project managementand contractor costs
888 Next stages development including PMsurvey, design, specification and procurement(no legal or financial advice included) - £400kOwners Engineer and PM post procurement -£300k20% Contractor Prelims OH &P (exceptsupply interface and pipework)
Contingencies 366 20% (except supply interface and pipework)Totals 16,484
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Table 15-5: Capital Costs - Scenario 5 – UWE to City Centre Link - SERC onlyItem Cost
estimate(£k)
Notes
Heat extraction anddistribution equipment at theheat source
n/a Assumes network already reached UWE - noadditional costs for extraction
Pipework and installation(trenching, welding fittingsetc)
£ 9,685
300mm pipework incl trench, install, makegood, design and prelims - £1300/m trenchUWE to City Centre – 7,450m
Major infrastructure crossings– eg motorways, railways andwaterways
n/a Route makes use of existing crossings of M32etc
Interface equipment at eachheat demand connection
90 1 connections at £90k per connection
Project Costs includingdesign, project managementand contractor costs
518 Next stages development including PMsurvey, design, specification and procurement(no legal or financial advice included) - £200kOwners Engineer and PM post procurement -£300k20% Contractor Prelims OH &P (exceptsupply interface and pipework)
Contingencies 122 20% (except supply interface and pipework)Totals 10,415
15.6 POTENTIAL VOLUME OF HEAT SUPPLY
The actual volume of heat that can be supplied will depend on a number of factors including; theprofile of demand; the extent to which mis-matches between supply and demand can beaddressed by thermal storage (both central and local); and the down time for maintenance of theheat supply system. For the purposes of the assessment we have assumed the heat supply willbe able to meet up to 85% of the demand of the identified clusters with the remainder provided bylocal top up and standby boiler plant..
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15.7 VALUE OF HEAT SUPPLYà Assessing the value of the heat supply is potentially a complex area. There are a large
number of factors to be considered including:
à The commercial arrangements between strategic network operator and the cluster operators
à The end user customer types – e.g. domestic, large industrial or public sector
à The off-set cost of fuel – e.g. gas into boilers
à The off-set cost of carbon – e.g. CCL, CRC or EUETS payments may be avoided by thecluster operator
à Any displacement of income - e.g. the revenue a cluster operator may obtain from operationof gas fired CHP to generate electricity
à The off set of plant maintenance costs - e.g. the cluster operator may reduce maintenancecosts for boilers etc.
à The offset of plant installation or replacement costs – for a cluster expansion or end of lifereplacement of boilers and/or CHP units
All these elements would need to be the subject of detailed assessment in future stages - andwould ultimately be finalised only through commercial negotiations.
For the purposes of this assessment we have established a common heat value as follows:
Cost offset Value (£/MWh) NotesNatural gas 26.00 Based on commodity price of
2.0p/kWh plus 30% fortransport and supplier margins
CCL 1.95 Rate as of 1 April 2016CRC 3.05 Based on £16/Tonne CO2 and
191kg CO2/MWh gasTotal cost of gas 31.00Cost of boiler Heat 36.47 Based on seasonal boiler
efficiency of 85%Value of heat 35.00 Small discount to overall cost
15.8 POTENTIAL RETURN ON INVESTMENT AND CARBON SAVINGS
OUTLINE CASH FLOWS
The tables below present an outline assessment of the costs and revenues for a potentialstrategic network. An indication of the potential carbon savings, assuming that heat offset is fromboilers at 85% efficiency, is also provided.
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Scenario 1 CPNN Southmeadand UWE
Base Heat Load MWh 136,592
Heat supplied 85% 116,103Heat Revenue £35.00 £4,063,607Heat Costs £3.0014 £348,309Net Revenue £3,715,298Capital Costs £33,905,800Simple payback years 9.1CO2 savings Te/year 26,089
Scenario 2 CPNN Southmeadand UWE
Base Heat Load MWh 136,592
Heat supplied 85% 116,103Heat Revenue £35.00 £4,063,607Heat Costs £5.00 £580,515Net Revenue £3,483,092Capital Costs £32,905,800Simple payback years 9.4
CO2 savings Te/year 26,089
Scenario 3 CPNN Southmead
Base Heat Load MWh 85,321
Heat supplied 85% 72,523Heat Revenue £35.00 £2,538,312Heat Costs £5.00 £362,616Net Revenue £2,175,696Capital Costs £26,885,200Simple payback years 12.4
CO2 savings Te/year 16,296
14 Heat cost for this option is based on weighted average of Nexterra and SERC heat costs – heat fromNexterra would likely be prioritised but this heat source could only supply approximately 50% of the totalsystem demand based on typical 8000hrs per year operation for this type of plant
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Scenario 4 CPNNBase Heat Load MWh 51,221
Heat supplied 85% 43,538Heat Revenue £35.00 £1,523,815Heat Costs £5.00 £217,688Net Revenue £1,306,127Capital Costs £16,483,600Simple payback years 12.6
CO2 savings Te/year 9,783
Scenario 5 UWE to City CentreBase Heat Load MWh 58,76215
Heat supplied 85% 49,948Heat Revenue £35.00 £1,748,170Heat Costs £5.00 £249,739Net Revenue £1,498,431Capital Costs £10,414,600Simple payback years 7.0
CO2 savings Te/year 11,224
15 This is the current estimate of the heat demand for the Temple and Redcliffe District heatingload serving; Redcliffe phases 1, 2a and 2b and St Philips. The pipe would link up the UWEcluster (which is the most viable and closest load to the City Centre) with the proposed EnergyCentre at the Great Western Refuse Transfer Station in St Philips. The load is subject to change,pending BCC approval.
It should be noted that in this assessment we have not included for operational costs other thanpumping and costs of heat losses which are incorporated in the costs of heat. It is assumed thatthe maintenance of the plant at the heat supply points would be undertaken by the heat suppliers.It is not at this stage clear how the network would be managed and owned. There would be somemaintenance costs associated with the heat interfaces at the heat users. There would also besome costs associated with the administration of the metering and billing. These costs should berelatively minor in relation to the volumes of heat being provided.
DISCUSSION
Of necessity, this high level assessment can only provide an indication of the potential economicperformance of a scheme of this type. It is very unlikely that the whole of the network from SERCto UWE could be installed as a single project. The build out of this type of scheme is likely to takeplace over 5 – 10 years and so simple payback assessments are a very blunt tool. The level ofassumption required to develop a more sophisticated financial assessment without significantfurther investigation would, however, mean that the assessment would be at the same time morecomplex and likely less helpful. We have therefore stuck with simple payback to provide a clearinitial indication of likely viability.
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This then raises the question: what payback period should be expected/may be required? Theinfrastructure that makes up the vast majority of the capital costs of the network would be verylong life assets. Typically design life for these pipe networks are 40 years or more and networksinstalled in the 1960s and 1970s are still operational without wholesale network replacements. Inthis context paybacks of 10-15 years are not excessive. It would however not be normal forprivate companies in the DH industry to invest to this level with such long returns anticipated.This type of investment is typically only undertaken by regulated industry with a monopoly – e.g.water and electrical distribution.
It can also be seen that the likely initial network connection from SERC to Cribbs Patchwayprovides the longest payback and could therefore be considered the most problematic. Tounderstand the sensitivity of this initial installation to heat loads we have sought to find at whattotal connected heat load payback would fall below 10 years. The results of this sensitivity areshown in the table below:
Scenario 4 CPNNBase Heat Load MWh 65,000Heat supplied 85% 55,250Heat Revenue £35.00 £1,933,750Heat Costs £5.00 £276,250Net Revenue £1,657,500Capital Costs £16,483,600
Simple payback 9.9
This implies that an additional 13.8GWh of demand, a 27% increase, would be required to reducethe payback by around 3 years.
Alternatively we considered at what level of heat revenue price the same goal could be achievedwith the following result:
Scenario 4 CPNN
Base Heat Load MWh51,221
Heat supplied 85% 43,538Heat Revenue £43.00 £1,872,115Heat Costs £5.00 £217,688Net Revenue £1,654,428
Capital Costs £16,483,600Simple payback 10.0
So the same goal would be achieved if the value of heat increased to £43.00 per MWh. Thiscorresponds to a base gas price of 3.15p/KWh with the same carbon (CCL) cost or a carbon priceof £45/Te CO2 with the same gas price.
In summary we would suggest that a strategic network as set out in the section would provide areturn on investment but that such investment would not be straightforward to obtain in the privatesector. It is likely that funding for the scheme would either require a significant level of publicinvestment at low cost or for the finance to be underwritten to a large extent by a public body.
16 APPENDIX A: HEAT DEMAND PROFILESTable 16-1: DHW and space heating profiles
DHW profiles Space heating profilesHotel
Leisurecentre(with pool)
Leisurecentre(dry)
Residential
Office
Stadium15
Combined hot water/space heating profile:
15 Profile obtained from previous project undertaken by WSP | PB. Demands shown here are the general, non-match day loads (e.g. office space, banqueting, shops,conference facilities etc)
School
University- offices
StudentUnion
Refectory
Studenthalls ofresidence
The following are the specially developed profiles:
DHW profiles Space heating profilesBAE Filton - CPNN(non-domestic uses)
Note – the profile for CPNN was developed through considering the percentage make-up of the non-residential heatdemands by use type
Accolade Wines N/A
Note – Accolade Wines has 24 hour operation. Gas use is fairly steady throughout the year, with the only use of gas beingfor office hot water and clean in place (CIP) use. There is no site space heating.
17 APPENDIX B: CONSUMER SIDE COSTSUMMARYA summary of consumer side CIU costs is provided below.
Table 17-1: Cribbs Patchway estimated CIU costs
Site name CIU size CIU costAtkins 2,067 £31,000Aztec Hotel & Spa 2,763 £34,000BAE Filton - CPNN - non-residential 22,110 £925,000Callicroft Primary School 264 £16,000Cavendish Nuclear 442 £19,000Hilton Bristol Hotel 2,491 £33,000Holy Family Primary School 200 £15,000Patchway Community School 1,427 £28,000Patchway Locality Hub 326 £17,000Rolls Royce 11,415 £76,000St Chad's Primary School 171 £15,000Stoke Lodge Primary School 285 £16,000Total cost £ 1,225,000
Table 17-2: Accolade Wines estimated CIU costs
Site name CIU size CIU costAccolade Wines 1,251 £ 27,000
Table 17-3: Southmead Network estimated CIU costs
Site name CIU size CIU costBadocks Wood Primary - Southmead Childrens Centre 171 £ 15,000BAE systems 1,785 £ 30,000Charborough Road Primary School 243 £ 16,000Filton Sports & Leisure Centre 556 £ 20,000GKN Aerospace 293 £ 16,000Horfield Leisure Centre 525 £ 20,000South Gloucestershire & Stroud College 4,495 £ 39,000Southmead Hospital 11,623 £ 76,000Total cost £ 232,000
Table 17-4: UWE network estimated CIU costs
Site name CIU size CIU costBristol Rovers/ UWE stadium 3,829 £37,000Frenchay HospitalHarry StokeHewlett Packard 2,484 £33,000Higher Education Funding Council 705 £22,000Holiday Inn Bristol-Filton 2,511 £33,000Land East of Coldharbour LaneLand East of Harry StokeMoD Filton Abbey Wood 14,666 £84,000Romney House - 6 digit read 471 £19,000ThalesUWE LOADST-block - office/laboratories 1,033 £25,000Ecc - exhibition / conference facilities 895 £24,000W - refectory 137 £14,000Energy centre - plantFbl p1 - academic/office 806 £23,000Fbl p2 - academic/office 456 £19,000Library zone - libraryCanopy - prof. Services (office) 47 £13,000Canopy student accom. (p3) - student accommodation 827 £23,000Student union - student union 136 £14,000Sa2 (p2) - student accommodation 1,206 £26,000Total cost £409,000
18 APPENDIX C: PHASED AVONMOUTH SEVERNSIDE NETWORKDEVELOPMENTThis section presents images illustrating the phased development of a network (though clusters joining together) across the Avonmouth Severnsideregion, and the growth of potential new development loads over a 10 year time frame.
Figure 18-1: 2019 network
Figure 18-2: 2021 network
Figure 18-3: 2023 network
Figure 18-4: 2025 network
Figure 18-5: 2027 network
Figure 18-6: 2029 network
19 APPENDIX D: PROCESS STEAM USE IN THE VICINITY OFSERCFollowing the Priority Sites and Risk Workshop held at SERC on 4th November 2015, this project was asked to present the considerations forsupplying a limited amount of high-grade heat to potential customers in the vicinity of SERC. This heat would be either in the form of steam, or hightemperature hot water (HTHW).
It is believed that the proposition of affordable steam or HTHW may be attractive to manufacturers with heat intensive processes and thus supportthis strategy, although to date no suitable users have been identified in the vicinity of SERC.
Avonmouth and Severnside is a popular location for chilled distribution centres, and there is the potential to develop a low-carbon ‘cool zone’powered by steam driven absorption chillers utilising steam from SERC. The considerations for this are outlined in the previously issued report:“Avonmouth & Severnside Heat Mapping Report”.
But there are a number of other industries which rely heavily on steam for manufacturing and processing. These are the types of businesses whichwould benefit most from a contract to supply low carbon heat directly from SERC. Some of those industries are listed below.
Industry Heat Requirement: Description
Brewing & distilling Steam and water required for brewing & distilling as well as bottle washing,cleaning in place (CIP) and sterilisation.
Food and beverage manufacture Uses include proving of bread, steam pasteurisation, fat rendering, potatopeeling, and blanching, as well as sterilisation and cleaning as with brewing anddistilling.
Oil & petrochemical Many uses across the industry, including petrochemical processing.
Pharmaceuticals Sterilisation, process use and general HVAC. Note that process 'clean steam' issubject to strict purification standards.
Paper and pulp industry Steam treatment of wood prior to pulping.
Tyre manufacture Used in the curing part of the process to stimulate the chemical reaction betweenthe rubber and other materials.
Universities & research Sterilisation and process use.
Waste water & sewage sludge Thermal hydrolysis of sludge to kill pathogens prior to anaerobic digestion.
These industries are often familiar with the beneficial economics of installing Combined Heat and Power plant on their own sites. Hence the keypotential benefits of a high-grade heat DEN for these industries may be:
à The avoided capital cost of the installation of CHP or other low-carbon plant
à The avoided space requirement for substantial heat generation plant
à The avoided planning requirement for flues for on-site boiler plant (assuming that the DEN is configured to provide sufficient resilience to meetindustry needs)
à The additional low carbon benefit that could arise from a DEN
à The ‘renewable’ component of the DEN heat supply
à Avoiding the need to reject ‘low-grade’ heat under an on-site CHP configuration (e.g. applies to sites where there the higher-grade heatrequirements are not matched by low-grade heat requirements)
20 APPENDIX E: NEW EARTH SOLUTIONS20.1 BUSINESS CHANGES
During the project, in discussions with employees of the New Earth Energy Recovery facility in Avonmouth, information came to light regarding theownership of the business, and the technology. For the purpose of avoiding confusion and to maintain the terminology used during the project, theplant has been referred to as New Earth Solutions during the course of this report.
Moving forwards, stakeholder should be aware that New Earth Solutions, which developed the thermal technology implemented at Avonmouth hassold their technology business, previously called NEAT (New Earth Advanced Thermal) to a collection of private investors. This new company iscalled Syngas Products Ltd. The site in Avonmouth which houses the thermal treatment power generation plant has also been sold, and is nowoperated as Avonmouth Bio-power Energy.