Presented by:

Felix Chiu: Mechanical Engineer (CMU 2014)

David Doctor: Chemical Engineer (Texas A&M 2014)

Abhi Kelkar: Mechanical Engineer (CMU 2015)

• Increased demand for renewable energy

• Non-Aesthetically pleasing

• If wind turbines were to be placed all along the coast of California (MW? for this, shorten), ~15% of the state's fossil fuel production could be replaced with wind energy for a total of ~25 GW of power per year

• Great Lakes

• East Coast

o Cape Wind Project, Cape Cod, Massachusetts

• Gulf of Mexico (Oil Rig Retrofitting)

o Costly to buy and retrofit turbines and lines

• California

o Coast of Mendocino County

o Chosen because it's been overlooked

o Distant from major populations

o Close to a power sub-station in Fort Bragg, CA

o Consistently strong wind speeds

o ~10-40 miles off the coast

• Average Wind Speed: 10 [m/s]

• Distance From Shore: 10-30 miles

• Location of Substation: Fort Bragg, CA (12-32 miles from proposed wind farm)

Mitsubishi 7 MW Offshore CVT Turbine

Advantages • 7 MW provides lots of power • Uses new CVT (Continuously

Variable Transmission) technology in wind turbines for more efficient gearing and power generation

• Mitsubishi is a trustworthy manufacturer of electronic goods

Developed Post-Fukushima Incident

Siemens SWT-3.6-107

- Used in the Wanley Wind Farm, off of the west side of England

- Quantity: 102

- 367 MW total

Vestas V90-3MW - Used in the Thanet Wind Farm, off of the east side of England - Quantity: 100 - 300 MW Total

Wind Lens Technology

Overview • Lens diverts minizimes density of

wind behind the turbine by diverting wind away through the curvature of the lens

• Lower Air pressure behind turbine is maintained with lens, creating a larger pressure difference between the input and output sides of the turbine

• Developed post-Fukushima incedent

Advantages • More efficient wind turbines • Requires lower wind speed for

energy generation • Quieter

• Variables

o vi=vwind entering turbine

o vf=vwind exiting turbine

• If vf=0, 100% of KE would be converted to ME, but no new wind would be able to enter turbine without giving some of the KE to the stagnant wind after the turbine

• In order for wind to continue moving through the turbine at a constant rate the wind behind must be moving at rate that has the KE difference between pre and post turbine wind which still allows wind to continue moving through the turbine at the same rate

• E is maximized when v2/v1=1/3, substitution gives

= 16/27 or 59.3%

• Objectives

o Floating platform

o Transportable

o Operation at depth >80 [m]

o Interchangeable “clip” base allowing any-size turbine to be attached (allowing for tech advances)

• Inspirations

• Main Features

o hexagonal semi-submersible platform with ballasts at six outside posts, as well as center post

o Center is "hollow", with room for a turbine to be "clipped" in and attached

o The entire platform + turbine can be assembled onshore then towed to site

HVAC HVDC LLC (Line Commutated Converter)

HVDC VSC (Voltage Source Converter)

Maximum Capacity 800 MW at 400 kV 380 MW at 220 kV 220 MW at 132 kV

600 MW at 500 kV 350 MW at 150 kV

Effective Range <100km <500km <500km

Black Start Capability Yes No Yes

Relative Line Loss High Low Low

Conversion Loss 0% 4-6% 4-6%

Offshore Substation Space Requirement

Smallest Largest Medium

Installation Cost High Cable Cost

Small Station Cost Low Cable Cost

High Station Cost

More than LLC Cable Cost

+30% LLC Station Cost

In Operation Yes No Announced

• To reduce line losses to the shore, an underwater substation will be required to step up the voltage coming from the wind farm

• The line coming from this will connect to the grid at the substation in Fort Bragg, CA, and then to the rest of California

• It is estimated by scientists at Stanford that this wind farm in this location could power ~ 6% of CA's energy if around 600 turbines were put in place

LAYTONVILLE

FORT BRAGG

BIG RIVER

ELK

WI

1

101

M END OCI N O

20

1280 20 4010

Miles

No costs with wind turbines, comes from the companies using our platforms

O&M costs, cost of platform, transmission, substation

O&M: $1,000,000/year

Platform: $1,000,000 (onshore construction)

HVDC (800MW)

44,000,000 - transmission lines

124,000,000 – converters

HVAC (800MW)

140,000,000 - transmission lines

12,000,000 – substation

HVDC has significantly less transmission loss, however a 4-6% converting loss. Depending on the distance of the farm to the substation, the capacity of the farm, types of turbines being used, there is a varying break even point between the types of systems that must be analyzed for the most economically sound option to be made.

• Transmission lines

o capital price for investors

• New technology harder to sell

o Offshore wind stigma in US

• Getting investors in the United States

o most are investing in Europe and some of Asia

• Local Opposition

o Past wave energy project was protested

As the offshore wind market matures, the need for more platforms will rise, and the costs of retrofitting old platforms or constructing new ones becomes more unwieldy. This Capstone project proposes a standardized offshore floating platform to which turbines of any size from any manufacturer/designer can be installed. The northern California shore was selected as the area for which calculations were done, but the eventual goal is for a platform that can operate anywhere, with any platform, as the offshore wind market evolves.

http://en.wikipedia.org/wiki/Semi-submersible

http://www.lorc.dk/offshore-wind/foundations/floating-support-structures

http://www.greentechmedia.com/articles/read/a-power-plant-for-wind-and-waves/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+greentechmedia%2Fnews+%28Greentech+Media%3A+News%29&utm_content=Google+Reader

http://mendocoastcurrent.wordpress.com/2008/10/21/the-danish-poseidon-wave-energy-project/

http://www.bluehgroup.com/product/phase-1.php

http://www.marineitech.com/index.php?option=com_content&view=article&id=67&Itemid=77

http://www.marineitech.com/downloads/WindFloatBrochure.pdf

http://www.youtube.com/watch?v=vQexzNg_e9A

http://www.energy.eu/publications/a07.pdf

http://www.kpmg.no/arch/_img/9686536.pdf

http://en.wikipedia.org/wiki/High-voltage_direct_current

http://en.wikipedia.org/wiki/High_voltage

http://en.wikipedia.org/wiki/Floating_wind_turbine

http://en.wikipedia.org/wiki/Skin_effect

http://en.wikipedia.org/wiki/Alternating_current

http://os-j101-2010-10

http://www.eesi.org/files/offshore_wind_101310.pdf

http://rredc.nrel.gov/wind/pubs/atlas/chp3.html