Setting A Different Tack…

Brian D. Kuhn, DirectorOffshore Wind Power Systems (OWPS),

a division of OWES, LLC

A New Architecture For Solving The Problems Facing

Offshore Wind Projects

2nd Annual New England Marine Renewable Energy

Technical Conference - 11/2/2010

It’s Not A Secret: Offshore Wind Faces Challenges

Source: DOE NWX National Renewable Energy Webinar, September 2010

It’s Not A Secret: Offshore Wind Faces Challenges

Source: DOE NWX National Renewable Energy Webinar, September 2010

The quest for ever increasing rotor sizes

has begun reversing the economy of scale curve – especially offshore.

The Offshore Wind Industry Faces Challenges:

"Sadly, it would seem we have not derived benefits from learning, scale and technological improvement over the last five years," says Rob Hastings, director of the marine estate at the UK's Crown Estate. "We have, indeed, gone backwards.”

July 12, 2010 in Recharge News

Today’s designs are basically terrestrial turbines (3 bladed, HAWT, monopole designs ‘stuck in mud’)

placed in shallow waters (<30m) – not specifically designed for where most of the energy is.

Solutions Are Needed

Whether coastal machines , or ‘floaters’ to get us to where the winds are far greater and the opposition is less:

A different design is needed; none has achieved ‘market lock’.

Solutions Are Needed

•9 of 11 projects currently being tracked in US along the eastern seaboard are within 21 km of shore.

•The wind resource potential at 5 to 50 nautical miles off the US coast is estimated to be more than the total currently installed electrical generating capacity of the United States (more than 900 GW)

97,975 vs 809,725 mW

Source: Energy From Offshore Wind, NREL – Butterfield, Musial 2006

OWPS architecture was designed from the beginning with the ocean in mind. Whether

shallow OR deep water, it inherently addresses

many of today’s problems.

Although the architecture might seem new, it’s really from an old name in wind energy…

William E. HeronemusNaval Architect, Wind Energy Pioneer, Teacher

AWEA Lifetime Achievement Award - 1999

Naval Architect, Captain USNProfessor, UMass Renewable Energy Lab

World-Class Authority on Offshore Systems

Patent Holder of many offshore designs

OWPS concepts based on the work of

OWPS Uses a Different Wind Architecture – the Multi-Rotor Array (MRA):

Major Advantages:

Smaller, Lighter Components result in

Volume Manufacturing

‘Down tower’ Weighting (low CG & met centric

height) perfect for ‘floaters’

Self-Yawing Tethered, orTraditional Platforms

,

How OWPS designs solves current industry challenges:

The concept of the multi-rotor array and its corresponding weight and cost reductions

have dramatic implications on the entire offshore project.

Current Technology Challenge: Cost of Construction Due to Huge Rotors

Huge blades (up to 200’+ long) built as ‘one up’ construction

Generators the size of houses – 300’ in the air

All the weight is up-tower, increases tower and foundation costs and loads, hard to float

Work done at sea costs ‘8-10 times’ that as on land

Results in higher than terrestrial costs: $6,000+/kW vs <$2,000/kW

OWPS Technology Answer: Lower Turbine Costs/mWMany rotors are better than one…Multiple smaller rotors favor volume manufacturing of more lightly loaded blades

High use of ‘off-the-shelf’ components

Scalability via # of rotors, not size of blades

Tower superstructure weight and cost reduced via:Alternating rotors counter-rotate, nulling out gyroscopic moments and reducing loading

Space frame (lattice) designs used, monopoles not requiredWeight of generation moved from nacelles down to floating hull or platform and aggregated. ‘Down-tower’ power.

Higher Specific Yield (kW/m2) without violating Betz Limit

Ability to optimize pitch angles to take advantage of wind speed at respective tier levels

Shorter blades easier to fabricate and install/kW Smaller rotors more responsive to changes in wind speed

turbulence Smaller blades can be made with thinner cross-sections,

gaining aerodynamic efficiencies Ability to run rotors at higher tip speeds ratios at different

tier wind speeds Asymmetric placement of lighter rotors along vertical axis

increases effective overall ‘hub height’.

OWPS Technology Answer: Lower Turbine Costs/mWMany rotors are better than one…

With weight down-tower and ‘out of the crow’s nest’, Center of Gravity (G) is lowered and Metacentric Height (GM) is decreased – vastly improving stability for traditional and ‘floating’ designs. Down-tower power makes ‘wind ship’ naval architecture more cost effective. WEH coined term ‘Wind Ships’, and envisioned an armada of them along coasts.

OWPS Technology Answer: Lower Turbine Costs/mWMany rotors enable a better architecture for off shore wind applications…

Current Technology Challenge: Costly Installation and ServiceLarge rotors require huge specialized cranes mounted on vessels

Single machine downtime is costly, encouraging repairs in foul weather

Lack of Portside staging and fabrication sites

Use of On-Board Jib Crane/Hoist simplifies installation and repair/replacement of rotors or components

Loss of single rotors has minimal impact on overall output, allowing service to be scheduled in better (less costly) weather

If Wind Ship: towed to location and moored via umbilical.

If Wind Ship: self-yawing, moving freely within watch circle

OWPS Technology Answer: Easier Installation and Service

Current Technology Challenge: Lack of Service FleetSize of specialized vessels required to transport and lift rotors and towers are huge

Jones Act requiring US flagged vessels – there are none

Lack of Fleet is a real barrier to entry, time and money sunk costs before anything is operational

Small rotors allow use of on-board jib boom/hoist

Jones act not an obstacle – vessels available or can be reconfigured

Wind ships: Towing to site like a flip-ship

OWPS Technology Answer: Need for large special purpose vessels eliminated

Sprite graphic showing rotor going up and down

Current Challenge: Permitting and NIMBYISMNear shore projects will face the largest opposition

Near shore projects involve the most State and Federal jurisdiction

What’s not to like???

Floating designs can be located farther offshore – ‘over the horizon’

Greater wind energy resource helps economics Out of Sight means more politically supportable

OWPS Answer: Out of Sight – Out of Mind

OWPS continues to refine and validate WEH designs

Several US & Int’l Patents Filed –

IP includes designs on both Multi-Rotor Arrays and hull designs for floating ‘Wind ships’

OWPS continues to refine and validate WEH designs

•Scale Testing of Multi-Rotor Array design at Langley Wind Tunnel.

•Computational Fluid Dynamics (CFD) analysis confirms little interference between rotors

OWPS continues to refine and validate WEH designs

Garrad Hassan & Partners Ltd., wind energy consultants (now part of

Germanischer Lloyd) confirm primary scaling benefits of the technology, issue

report: “Multi-Rotor Wind Energy Systems”

Finite element modeling for a 5 MW system conducted by Aerotrope Consulting Engineering, issue report: “OWES 5.0 MW

Multi-Rotor Support Structure and Yaw System Study” 

OWPS continues to refine and validate WEH designs

Present – continuing work on terrestrial version of MRA by OWES, LLC

Need graphic, wordsmith

OWPS continues to refine and validate WEH designs

Now forming development consortium for prototypes and pilot plants

Need graphic, wordsmith

Take Aways:• Offshore wind environment (coastal or deep) demands

new architecture, especially for floating ‘wind ships’

• Wind ships allow us to go into deep water - after the lion’s share of ocean winds - cost effectively

• It may look like a ‘sea change’, but OWPS approach is based on sound naval architecture and application of

well known rotor technologies

• A new consortium is being launched –

Shipmates Wanted

FINIOffshore Wind Power Systems

a Division of OWES, LLC

We’re Taking a Different Tack –

Contact:Brian D. Kuhn

DirectorOffshore Wind Power Systems

Brian.Kuhn@OffshoreWindPowerSystems