Floating Wind Turbines: Encouraged, Challenging


Floating Wind Turbines: Encouraged, Challenging
Two of five floating wind turbines being prepared in Stord, Norway, in June 2017 to sail off to Peterhead, Scotland, to establish the world's first floating wind farm, Hywind Scotland Pilot Park. © Terje Aase

Although the United States government is aggressively encouraging future growth in floating offshore wind energy because of its vast potential, projects face several regulatory and technological challenges, speakers said during an online webinar about the topic.

Approximately two-thirds of U.S. offshore wind energy potential has water depths for what are called fixed bottom wind energy, Daniel Kennedy, director of engineering for Diamond Offshore Wind, said during the webinar, citing Department of Energy findings.

“Turbines can be installed directly at the port, eliminating the need for [wind turbine installation vessels], which are in short supply,” Kennedy said during the Riviera Maritime Media webinar, “Floating wind: the new energy frontier in the U.S.,” on July 11.

According to a White House factsheet released in March, deep-water areas that require floating platforms are home to two-thirds of America’s offshore wind energy potential, including along the West Coast and in the Gulf of Maine. To encourage such projects, the U.S. Department of Energy launched the Floating Offshore Wind Shot, aiming to reduce costs by more than 70% by 2035. The DOE, the U.S. Department of the Interior, and the departments of Commerce and Transportation hosted an inaugural summit convening federal, state, tribal, labor, industry, and community leaders to advance U.S. leadership, and DOE is advancing foundational science and prize competitions to accelerate breakthroughs. The Department of the Interior set a goal to deploy 15 gigawatts of floating offshore wind capacity by 2035 – enough to power over five million American homes.

Numerous foundation technology options are under development, Kennedy noted. The White House’s initiative includes research and development investments, with prize competition for floating offshore wind platform technologies. The floating foundation can be towed back to port in case of need for a major intervention.

Kenney noted there are currently no floating offshore wind ports in the U.S. for floating foundation fabrication, launching or wind turbine generation integration; however, ports with the more than 100 acres of space needed for commercial projects have been proposed in Maine and in Humboldt and Long Beach in California.

A challenge to floating wind becoming more widespread in the U.S. is a shortage of quality space on the country’s west and east coasts, which will create a supply chain bottleneck, Jeff Andreini, vice president of supply chain services company Crowley Wind Services, noted.

According to Andreini, only Humboldt, in northern California, and Long Beach, in the state’s southern end, are scheduled to be developed to support floating wind energy on the U.S. West Coast. The U.S. East Coast has further challenges with terminal size, location and restrictions, he added.

The absence of vessels on the U.S. West Coast that can supply the needed infrastructure for transportation and installation of floating wind, “creates an opportunity for naval engineering firms, shipyards and manufacturers for design and construction.”

He noted that California emissions standards will require vessels and ports to operate in the “greenest” fashion possible, opening up opportunities for electrification and development of alternatives fuels, such as hydrogen.

Charlie Papavizas, partner in international law firm Winston & Strawn LLP and chair of its maritime practice, said a federal issue under consideration is whether floating wind structures are considered vessels. “In the oil and gas industry in the Gulf of Mexico, they have a variety of things in water – some floating, some fixed,” he noted. “Some called facilities, some called vessels, some called structures. They all have different regulatory regimes depending on how they are classified. It’s still not clear with floating objects that have turbines on them, what they will be classified as.”

Another question is whether floating platforms with wind energy turbines on them will be registerable as vehicles, and then whether it would be possible to place vessel mortgages on them. “Some offshore wind structures elsewhere in the world have been registered as vessels,” he added. “The possibility of vessel mortgages would of course help with financing.”

He noted that in California, Oregon and Washington states’ vessel emissions standards play a big role in vessel emissions, including which vessels can be used and how they’re utilized, which also has ramifications for floating offshore wind energy.

Gear oil accounts for the highest volume of lubricants used in wind turbines, followed by hydraulic fluids and greases. Gear oil is used for the majority of wind turbine gearboxes, though they aren’t needed in some newer direct drive turbines. Hydraulic fluid is used in wind turbine hydraulic systems that control the pitch – the angle of the blades in relation to the wind. Grease gets applied to several wind turbine locations: the main rotor shaft bearing; the yaw bearing, pitch or blade bearings; pitch drive gears; and generator bearings.