Major Transmission Project Planned for the Atlantic Coast

California rich in offshore wind

The amount of wind blowing off the California coast has high potential. Lawrence Livermore National Laboratory atmospheric scientists are working with a Norwegian company to leverage that wind as a valuable energy source. LLNL has signed a memorandum of understanding with Sway, a renewable energy company that has developed floating towers for placing wind turbines in deep water. Though California has not yet approved offshore wind turbines, Sway has launched a prototype off the coast of Norway on June to demonstrate how the system could work in the Pacific Ocean.
Towers for offshore wind turbines typically sit in water as much as 30-m deep and are anchored to the ocean floor. Based on technology that was originally used for deep-sea oil drilling, Sway has developed a floating tethered tower that allows siting turbines in water 60 to 400-m deep.
“California has an abundance of deep-water wind resources, so this is an opportunity for the state,” said Nalu Kaahaaina, LLNL’s Low-Carbon Energy Program leader. “This technology is clean, reliable. and even more consistent than traditional onshore wind turbines.”

Power generation from offshore wind turbines is significantly higher than from units onshore. “The wind blows all the time at some offshore wind resources in California,” says Roger Aines, LLNL’s Carbon Fuel Cycle Program leader. “If Sway has success in Norway, the technology could be useful in California.”

Lawrence Livermore has a history in atmospheric studies. Its scientists will provide their expertise in wind energy to help launch the project internationally, nationally, and regionally. For instance, the Laboratory works on numerical weather prediction models to predict power generated by the wind, so that wind farms operate to max potential.
Predictive time frames range from an hour to days ahead of time. LLNL scientists plan to include ocean circulation and wake-turbulence studies to determine the most suitable sites for deep-ocean wind farms. Using this data, Aines says wind operators can find the best locations for wind farms, on or offshore. In California, the only option for offshore wind turbines would be in the deep ocean, away from coastlines.
Offshore wind projects in the U.S. must strike a balance between technological and economic challenges and adhere to more demanding environmental requirements to be successful. The latest generation of offshore turbines is equipped to meet the challenges of the ocean environment and weather extremes, which can limit access for routine maintenance. According to the American Wind Energy Association, wind energy made up 2.3% of U.S. electricity by the end of 2010, up from 1.8% a year ago.

LLNL
Llnl.gov

Europe’s Financing Lessons for U.S. Offshore Developers

Turbine manufacturer Areva Wind recently won a contract worth €400 million to supply 40, 5-MW turbines for the Borkum West II offshore wind farm in the North Sea near Germany. Under the agreement with Trianel, an association of German urban electric utilities and communities, Areva will provide the turbines, commissioning, and maintenance services. Foundations, transport, and erection offshore are excluded from the scope.

What’s more significant is this project’s financing. Previously, offshore wind farms were supported by government-sponsored export credit agencies and only financed by banks after final commissioning. “Given the newness of offshore construction, banks are reluctant to take risks because they judge that construction risks there are higher than onshore work,” says Areva Renewables’ VP Project Control & Finance Jay Boardman.

Borkum West II is stretching the prevailing boundaries for European offshore non-recourse financing. European banks now accept a number of risk features, such as non-recourse, multi-contract, and construction-phase financing, which up till now they have not.

Boardman explains how non-recourse financing works. A special-purpose company funds project assets with debt from banks and equity from shareholders. Project revenues repay the debt and reward the shareholders. If the project fails, banks have recourse only to the project company’s assets for repayment and cannot pursue the shareholders for any non-repaid debt. Non-recourse financing corresponds well to project developers’ objectives, but banks require greater security or less risk for giving-up recourse to shareholders. In total, 11 banks financed about 500 M€ of debt.

The U.S. market will likely develop in a similar way by starting with a couple of smaller projects in state waters, such as Block Island and a 20-MW project in New Jersey. “With the experience we’ve gained overseas, we would like to bypass in the U.S. a lot of the small-project ramping up that Europe has gone through,” says Cuevas, “and jumpstart by building an offshore wind industry representing thousands of megawatts.”

Areva Renewables’ Director Offshore Wind Business Development Steven Cuevas adds, “That’s is why the first financing of Areva’s turbines makes a good story. This project has risk characteristics banks were willing to finance on their own, without the backup of the sponsor’s balance sheet. These are the most important aspects to the project’s financeability. Project company assets are the only thing at risk.”

Areva had European Investment Bank (EIB) support to decrease commercial bank lending. However Boardman says there was no import-export bank support to bear part of the project risk, which has been the typical European way to sell wind turbines produced in Germany for other European markets.

Since the financial crisis, banks are extremely risk adverse. The European Investment Bank has acted as a secure foundation to attract and build critical mass among commercial banks for these types of projects. Once the EIB signs onto a project, it brings a good portion of financing that helps other commercial banks get behind the project. “As the economy improves, and we show wind technology maturing with merit, banks are coming back in and willing to take a bit more risk,” says Boardman. “This is why Borkum West II is an exceptional project. It stands as the new reference for non-recourse financing.”

Capital markets are warming up, adds Boardman. “There are awesome funding needs for equity and debt. Conditions are coming together to bring commercial banks into offshore wind projects. This is another shift, European banks becoming less risk adverse because projects are showing merit. Alpha Ventus and other pilot projects have provided feedback to make banks comfortable.”

In the past, European banks usually waited until a project’s construction phase finished before stepping in with financing. “That takes one major risk element out,” says Boardman. “Banks often say, ‘If you want financing for a construction phase, start with a six-turbine installation before expanding it with 40 more.’” This staged approach was critical in getting financing needed from Day One, and keeping the non-recourse structure to ensure the project moves forward.

Offshore wind projects typically get rolling when there are at least two to four banks acting as Managing Lead Arrangers by assigning different responsibilities: financial analysis, technical due diligence, syndication, and documentation. Because they are growing to understand non-recourse financing, European banks are more willing to support offshore wind power.

A drawback is that the U.S. does not yet have an offshore wind industrial base. Cuevas says a key part of the offshore wind industry’s business model is job creation. “For example, assembling the 3,500 parts for our turbines and blades is estimated to generate 650 direct jobs (and 1,000s of indirect jobs in the supply chain) with an additional 500 service jobs during project operations,” he says. But this is an expensive industry to establish. “To build an offshore wind industrial base in the U.S., he says, we need to see a long-horizon market for more work. That is, the EPCs, suppliers, vessel builders, and operators unique to an offshore wind industry want to see an initial five-year horizon on projects to justify mobilizing the industry. Hopefully, by studying and validating what has happened overseas, we can take those lessons quickly to scale in the U.S,” he adds.

In terms of financing, Areva executives say large projects are the only way to justify building an industrial supply chain and making the large investments necessary to create a domestic industry.

Expect to see European banks involved in U.S. projects. “Many U.S. developers already have relationships with financiers and banks in Europe,” says Cuevas. “Those banks are more familiar with offshore wind-project risk profiles and technology, as well as warranties and guarantees that make a project successful. “So at an initial stage, lead banks may come from Europe and perhaps syndicate with some U.S. banks until the domestic firms are comfortable with the market. U.S. banks are still generally risk adverse, so it’s likely to see more experienced banks from Europe investing in the U.S.”

European pilot projects have acted as proving grounds, not just for the technology, but also for foundations, logistics, and project management. Banks have no boundaries, so they would be able to step in and use their financing skills and risk experience to put these U.S. projects together. “The good news is that offshore capacity factors have shown consistently better than what were expected,” says Boardman. “There will be a ramp up for the U.S., but it will be shorter than Europe’s.”

WPE

Vestas launches a 7

Vestas Wind Systems A/S has taken the wraps off its next generation offshore turbine, the  V164-7.0 MW with a rotor diameter of 164m. The company says North Sea conditions influenced the designs of the turbine.

President of Vestas Offshore Anders Søe-Jensen says the offshore wind market is set to significantly expand over the coming years, more so in some parts of the world than in others. “We expect the major part of offshore wind development to happen in the Northern Europe where conditions at sea are particularly rough. The V164 will provide the highest energy capture and reliability in this rough and challenging environment. This makes our new turbine a good choice for many UK Round-3 projects.”

Vestas says development ran on two separate parallel R&D tracks. One focused on direct drive and one on a geared designs. Finn Strøm Madsen, president of Vestas Technology R&D says the final decision went to a medium-speed drive train.

To ensure alignment between customer needs and features of this turbine, several experienced offshore customers were invited to provide input during development, resulting in a match between turbine specifics and customer business cases.

Construction of the first V164 prototype is expected in Q4 2012. Production is set for Q1 2015 provided a firm order backlog is in place to justify the substantial investment needed. The company says it has installed 580 offshore turbines, about 43% of all offshore turbines in the world.

WPE

European team to develop offshore-turbine installation vessel

A manufacturer of marine vessels and an international oil and gas services company have agreed to combine their fields of expertise to develop vessels for installing offshore wind farms.  Wärtsilä (www.wartsila.com) will provide the new installation vessels with ship design, electrical power generation, propulsion machinery, and high-end automation. Aker Solutions will supply the jacking system. The two companies will also offer a 24/7 global support service for maintenance, repairs, and component supply to the vessels.

The companies have selected the best technologies for this custom installation vessel. Five Wärtsilä dual-fuel engines will provide main and auxiliary power for the vessel which can operate on liquefied natural gas with low emissions. Heat from the engine will be used to supply drinking water and hot water for crew use. Absorption chiller units will provide air conditioning.

The market for offshore wind farms is rapidly developing as demand for renewable energy sources increase. Because North European offshore wind farms tend to be in shallow waters, 50m or less, so-called jack-up vessels are used for the installation work. At the installation site, the vessel lowers massive legs to the seabed on which the vessel is jacked-up until it is above the waves. A hydraulic grip system is used for this jack-up operation.

Aker Solutions will develop a continuous hydraulic-jacking system for truss legs, a design customized for turbine installation vessels. The jack mechanisms will have redundant systems and a rugged design for operations in harsh environments.

The vessel will fulfill the industry’s requirements for large deck space, sufficient crane capacity, year-round and all-weather operational capability, and cost-efficient operating systems. It is intended for work in the International Maritime Organization’s emission control areas.

“This vessel is already generating significant interest among those involved with the installation and maintenance of offshore wind farms,” says Riku-Pekka Hägg, Vice President, Wärtsilä Ship Design. “There is demand for a high technology and well equipped installation vessel with environmentally sound features. We expect to get the first orders this year.”

WPE

Recently upgraded turbine gets an up-rating

It costs millions to develop a new turbine so it makes sense to push the bounds of existing models. GE Energy has done so with the recently introduced 4.1-113 wind turbine. It says the 4.1-MW class machine brings a higher level of reliability to the offshore wind industry. The design builds on the company’s recent 4.0-MW unit (Windpower Engineering’s Turbine of the Month, July 2010), which is an upgrade of the company’s 3.5-MW direct-drive design. The company recently signed a contract to provide a 4.1-113 model and services to Göteborg Energi for installation in the Gothenburg, Sweden harbor in the second half of this year.

“It is the only direct-drive wind turbine designed for offshore today,” says GE VP Victor Abate. With fewer moving parts, explains Abate, the direct-drive unit provides a simple, reliable design with built-in redundancy and partial operation for major components, while focusing on keeping turbines operating reliably at sea. The direct-drive eliminates a costly gearbox which lowers operating expenses. It relies on a modular approach to maximize in-situ repair and reduce the need for large repair vessels.

The base design has been operating since 2005 on a coastal site in Norway, a harsh environment with high winds and turbulence. The company says the equivalent of 50 years of lessons learned are built into the 4.1-113. The design also draws on solutions developed for the company’s onshore fleet, including its Advanced Loads Control, sensors and algorithms that help reduce loads which are ordinarily passed to the machine and foundation.

Cape Wind contract for offshore wind power approved

The Department of Public Utilities (DPU) has approved the 15-year power purchase agreement between National Grid and Cape Wind Associates, as amended by a settlement agreement, following a five-month-long adjudicatory proceeding involving 17 intervenors and five limited participants.

The DPU concluded that the contract is cost-effective because its benefits well exceed its costs. It found as well that approving it is in the public interest, because no other renewable resource in the region matches Cape Wind in terms of size, proximity to large electricity load, capacity factor, and advanced stage of permitting; and because its bill impacts are in the range of 1 to 2%.

“This contract fulfills a statutory mandate under the Green Communities Act to facilitate the development of renewable energy generation, and it does so with strong protections for ratepayers,” said DPU Chair Ann Berwick. “It is clear that the Cape Wind facility offers significant benefits that are not currently available from any other renewable resource, and that these benefits outweigh the costs of the project. Not only does the contract support the largest renewable energy project proposed in New England, it provides protection for consumers against the volatility of fossil fuel prices for a portion of electricity purchases. We are fully persuaded that if Massachusetts is to meet its statutory renewables and greenhouse gas emissions reduction requirements, offshore wind, and Cape Wind in particular, will have to be part of the mix.”

The contract, which is for 50% of the output of the Cape Wind offshore wind facility, sets the initial price – for electricity, capacity, and renewable energy attributes – at 18.7 cents/kWh in 2013, and rising 3.5% annually for 15 years. After that, National Grid would have the right to a one-time extension of the contract for another 10 years on terms that could be below market rates.

The contract allows for upward and downward price adjustments based on a variety of contingencies. If Cape Wind is unable to tap certain federal subsidies, the price would go up, but under other circumstances the prices could go down, to the benefit of ratepayers. Specifically, should debt financing costs be reduced as a result of a U.S. Department of Energy loan guarantee, 75% of the savings would be passed along to customers in lower rates. Similarly, if actual project costs, as verified by an independent audit, fall to such an extent that the developer’s rate of return on debt and equity exceeds 10.75%, the contract price of electricity will be reduced to give ratepayers 60% of the benefit of the lower costs; if actual project costs are higher than anticipated and reduce this rate of return, the developer absorbs those losses without impact on rates paid by consumers. This mechanism in the contract assures that the developers of the project will not reap windfall profits.

The 300-plus page order approving the contract was issued recently, following three public hearings in the National Grid service territory held in June and 13 days of evidentiary testimony in September. The evidentiary record consists of 838 exhibits, 20 responses to record requests, and a 2,800-page transcript.

The order concluded that the contract met the DPU’s standard for long-term contracts under Section 83 of the Green Communities Act, as well as the Department’s standard for the public interest.

In terms of cost-effectiveness, the Department concluded that the costs would be outweighed by the benefits provided by the contract, namely assisting National Grid and the Commonwealth to comply with the state’s renewable energy and greenhouse gas emissions reduction requirements; providing National Grid the option to extend the contract beyond 15 years at a price that covers the remaining costs of operating the facility plus a reasonable rate of return; enhancing electricity reliability in the state; moderating system peak load; and creating additional employment.

Notably, the DPU found that the contract and the Cape Wind project will moderate electricity peak load in the region. In that regard, the DPU observed that wind data show that Cape Wind’s capacity factor would have averaged an impressive 76% during the region’s top ten historic peak hours. It concluded further that the project will create an average of 162 jobs per year for the 15 years of the contract—but many more than that during the two-plus year construction period.

In terms of the public interest, the DPU found that the Cape Wind project offers “unique benefits relative to the other renewable resources available.” In addition, the DPU found that the contract price was reasonable for offshore wind, which the Department determined to be needed to meet state renewable energy and greenhouse gas requirements. The DPU also found that the bill impacts that could occur as a result of the contract “are small relative to the volatility that electric customers regularly experience due to the fluctuations in wholesale electricity prices, and that the contract will mitigate that volatility.”

A second power purchase contract for the other half of Cape Wind’s power output, which did not specify a contracting party, was rejected by the DPU, but Chair Berwick said that any contract between other regulated utilities and Cape Wind on the same terms could be reviewed on a more expedited basis.

“The issues underlying this contract have been fully adjudicated in this proceeding,” said Chair Berwick. “If an identical contract comes before us, not all of the issues would require the same level of review.”

-www.mass.gov

Cape wind www.capewind.org

Floating turbines: the future of offshore wind

A new collaboration between Denmark Technical University (DTU) and international partners from the wind industry and research community will explore the idea of 20-MW floating turbines. The 4-year project called DeepWind was launched October 1, with Risø DTU coordinating the consortium of 12 international members.

“Our objective is to develop more cost-effective offshore wind turbines, rather than advance existing concepts that are based on transporting onshore technology to the sea environment,” says DeepWind Project Manager Uwe Schmidt Paulsen. “Offshore wind energy today is twice as expensive as onshore technologies. That means that there is plenty of room for improvement.”

Studies show that for sea depths exceeding 30-60 m, floating structures are economically more feasible than present offshore technology based on piled, jack-up, or gravity foundations. Members of the consortium say the cost of material and logistics used in these constructions is simply too high. Furthermore, floating wind turbines will open up the possibility of placing offshore wind turbine plants with excellent wind potential near large cities with a deep-water coastline in, for example, Europe, Asia, and North America.

Risø DTU scientists explain that the concept combines a vertical-axis wind turbine, new blade technology, and full power transmission and control system combined with a rotating and floating offshore substructure.  The basis for the vertical-axis wind turbine is the Darrieus design. This provides a very simple MW turbine, but also contains challenges, including the long sub-sea support structure needed. The concept also includes a direct-drive MW generator with its electronic control system at the bottom of the sub-sea shaft, together with the electrical power transmission cables. Combining the relevant technologies and designing the components properly will positively re-address the issues of distribution, cost, and competitiveness of the concept compared to existing technology.

Paulsen says the technology behind the proposed concept requires technological breakthroughs. “We need explicit research in a wide area of different technology fields and materials,” he says. “For example, we foresee research in the dynamics of the system, pultruded blades with adequate material properties, sub-sea power generators and converters, turbine control and safety systems, wave and current loading on the rotating and floating shaft, and also the mooring and torque absorption system.”

Researchers say one of the definite outcomes of this project will be the demonstration of a kW-sized wind turbine to be placed in open waters of Roskilde Fjord next to Risø DTU. In this phase, dedicated experiments will be carried out and simulation tools will be developed for design purposes. These will be used to design a 5-MW concept and evaluate the prospects of an up-scaled, future 20-MW turbine.

-www.risoe.dk/en

Maryland steps forward in offshore wind

Maryland is moving closer to bringing offshore wind to its coast. Gov. Martin O’Malley and the Maryland Energy Administration announced that the federal government has accepted planning recommendations made by the state. Maryland is only the second state in the nation to reach this point in the process (after Delaware).

“Today’s announcement marks another step forward for Maryland’s new economy,” says Gov. O’Malley. “By harnessing the wind resources off of Maryland’s coast, we can create thousands of green collar jobs, reduce harmful air pollution, and bring much needed, additional clean energy to Maryland.”

The Governor has made offshore wind a priority in Maryland’s efforts to generate 20% of its energy from renewable sources by 2022. A 1-GW offshore wind farm off of the state’s coast could create as many as 4,000 jobs in manufacturing and construction during the five-year development period, with an additional 800 permanent jobs once the turbines are spinning.

The western edge of the area for proposed wind generation is located about 10 nautical miles from the Ocean Citycoast and the eastern edge is about 27 nautical miles from the Ocean City coast.  Due to its proximity to planned wind farms in the Mid-Atlantic, as well as the deep water port and manufacturing infrastructure in Baltimore, the state is well positioned for offshore wind energy generation, as well as for ongoing construction and maintenance.

www.maryland.gov

Who’s offshore?

Many companies exhibited their offshore inventory at the AWEA conference in Atlantic City earlier in October. Here’s a look at a few and what they have to offer.

Vestas V112 3.0-MW offshore turbine

The V112-3.0MW Offshore is designed to take full advantage of wind conditions at sea. It’s well suited for high offshore wind speeds and low turbulence and has the IEC IB offshore wind classification. It features what the company calls the GridStreamer, which has a permanent magnet generator to ensure wider opertaion range of the turbine and reduced loss of power, along with a full-scale converter that offers excellent grid support, reduced drive-train loads, and high energy productions over a greater range of wind speeds. Other features include:

-large rotor diam. (112 m), 54.65-m blades for high yield even at low (below 12 m/s) and medium wind speeds

-nacelle cover has the ability to close the integrated air intake holes and service hatches, and is 6.8 m installed (3.4 m for transport)

-The GridStreamer has the ability to continue to operate even during a severe grid voltage drop, converting excess power to heat and being able to quickly down-rate to 20%

-voltage range is 0.9-1.1 pu, frequency is 47-53 Hz, max short-circuit level 25kA, power factor range: 0.9 capacitive/0.83 inductive (HV transformer)

REpower 6M offshore turbine

REpower’s 6M offshore wind turbine stems from its 5M predecessor. The IEC IB class design is based on the company’s philosophies including conservative component design, ease of transportation, and grid compatibility. The turbine has a safety system including individually adjustable blades (electrically controlled), redundant temperature and speed sensing system, lightning protection, rotor holding brake with soft-brake function, and automatic fire protection system. Other features include:

-a power rating of 6,150 kW

-offshore cut-in wind speed of 14 m/s and cut-out at 30 m/s

-rotor diam. is 126 m, with fiberglass-reinforced plastic rotor blades 61.5 m

-hub height is 85-95 m (site specific)

-frequency is 50 Hz

Siemens SWT-2.3 and 3.6 offshore turbine

Rotor blades are made of fiberglass-reinforced epoxy and manufactured through what the company calls its Integralblade process. This means the blades are cast in one piece in a closed process, leaving no weak points at glue joints. An automatic lubrication system for major components of the nacelle (main shaft, gear box, and yaw system) enables continued operation even if maintenance is severely delayed by weather.  The offshore turbines are normally mounted on tubular steel towers fitted with internal hoists and comply with all relevant grid codes due to a NetConverter system that uses full conversion of the generated power. Other features of the 3.6 include:

-107-m diameter, blade length 52 m, and hub height 80 m or site specific

-3,600-kW generator with 690 V

-cut-in wind speed of 3-5 m/s and cut-out of 25 m/s

-NetConverter system is a modular arrangement for easy maintenance. Power is transferred by DC from rectifier installed in nacelle to inverter in tower bottom, minimizing cabling losses and avoided complications  from nacelle-mounted transformer

GE 4.0-110  offshore turbine

Growing from a 3-MW turbine in 2005, to a 3.5-MW model in 2007, GEdevelops its 4.0-MW offshore turbine in 2010. The turbine is built around a permanent magnet generator, delivering high efficiency at low wind speed. With direct-drive technology, the turbine removes the single most costly failure in offshore, gearboxes, and replaces it with reliable, slow-speed  components designed for the offshore environment. With a spacious nacelle and internal hub access, the IEC class turbine offers maintenance and safety advantages. Other features include:

-rotor diameter of 110 m

-cut-in wind speed of 3 m/s and cut out of 25 m/s

-At just 10 rpm, magnets at the rotor tip move at about 188 m/min. The generator’s 20 sections or modules allow replacing a portion of it without a complete removal of the 90-ton unit.

-Two main bearings transfer axial and bending loads from rotor to bedplate for higher reliability. The unit also sports continuous close-wind tracking to capture more energy.

-No yaw brakes or hydraulics.

Gamesa G11X 5.0-MW offshore turbine

A progression from the G10X 4.5-MW turbine, Gamesa is developing the G11X designed for variable and often extreme marine conditions, inclement weather, and challenging accessibility. A multi-variable control system minimizes blade vibration and reduces blade loads up to 30%. A permanent magnet generator and full converter comply with demanding grid code and connection requirements. Because of it’s modular design, the system keeps running even if any of the individual modules fail. A two-stage planetary integrated gear box with dual bearing design improves reliability by using fewer parts and avoiding the use of high speed bearings. The blades feature an airfoil design and the nacelle is designed to be spacious for technicians and tools, helping to reduce overall maintenance times and ensure safety. Gamesa has partnered with American shipbuilder Northrop Grumman to launch a prototype in the U.S. The two companies plan to install two of the turbines by 2012. Other features include:

-rotor diameter of 115 m

-3 upwind blades

-hub height adapted to site requirement (75-100 m)