As design firms, builders, suppliers and observers consider the potential of the booming global offshore wind energy marketplace, the excitement is palpable.

Key players in the arena now see unprecedented levels of demand across worldwide locations to confront the looming impacts of climate change, challenge power-delivery norms and create a pipeline for economic growth, even as new building hurdles emerge.

“This is a revolution in the world in the next 15 years that is like the industrial revolution of the past,” says Matt Palmer, vice president of engineer WSP U.S. and manager of its offshore wind business. Tony Appleton, a sector veteran just named offshore wind director at Burns & McDonnell. terms it a "once-in-a-generation new concept, a new industry."

Offshore wind farms date to the 1990s, even earlier, with early ventures already retired. But the clean-energy resource has demonstrated an ability to scale up greater than other types of renewables, experts say, with better reliability and consistency. As such, the market and its machines have both developed dramatically.


With Europe’s commitment and much-improved production economics, it now accounts for two-thirds of the 15% rise—from nearly 105 GW last year—in offshore wind capacity in operation, construction or development, says British industry trade group RenewableUK. “The major piece of scalable growth in European utilities is offshore wind,” notes an April Credit Suisse research report. It also notes “credible plans” for 55.6 GW of offshore wind installed globally through 2025, up from a previous estimate of about 41.3 GW.

Five countries, led by the U.K., account for 75% of global capacity, RenewableUK says. “Although offshore wind started in Scandinavia, the U.K. is where … it was driven forward,” says Palmer. Britain’s 9% increase to 38.4 GW in projects at various stages is followed by Germany with 16.5 GW and the U.S. with 15.7 GW—a leap that surprised some industry observers.

“Simple math: for a 1,000-MW wind farm, you need far fewer wind turbines. It has driven down the levelized cost of energy.”

– Rich Baldwin, principal consultant, Denmark-based Ramboll

Philippe Kavafyan, CEO of turbine maker MHI Vestas Offshore Wind A/S, a joint venture of Denmark’s Vestas Wind Systems and Japan’s Mitsubishi Heavy Industries, told Standard & Poor’s that in the last 12 to 15 months, the U.S. “went from a potential market into the first large-scale commercial project … and we’re already talking about 20 GW.”

The U.S. passed developing markets in Asia and is ahead of China’s 12 GW and Taiwan’s 8.9 GW, for the present.

The new project surge coincides with offshore wind costs falling by half in recent years, with France just buying 600 MW at less than $56 per MWh and the U.K. set to pay $70 per MWh for up to 6,000 MW of new capacity, says RenewableUK, even as some forecasts see slower market growth in France and Germany. 

Turbine size is key, with early 2 and 3-MW models giving way to 9.5-MW capacity machines used on the U.K.’s just-completed Beatrice offshore wind facility and even larger ones being tested or contemplated.

“Simple math: for a 1,000-MW wind farm, you need far fewer wind turbines,” says Rich Baldwin, principal consultant at Denmark-based Ramboll, a leading offshore wind designer. “It has driven down the levelized cost of energy.” Credit Suisse said Siemens Gamesa’s new 10-MW turbine can cut the annual cost of energy 7% per year through 2024. The firm “would not need to invest in material new production capacity," the report said.

The Global Wind Energy Council, the Brussels-based trade group for the offshore and land-based wind power industry, now numbers 1,500 private- and public-sector members. Its first global market assessment released in June projects a minimum of 190 GW in a "business as usual" scenario, and up to 220 GW of total installations by 2030 with “upside” gains such as “game-changing” floating wind farms and new government commitments.

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New Players

Saudi Arabia, among the nations signaling a first-time focus on offshore wind power, just announced plans for 5 GW of renewables in its power mix to free up oil for export. Italy-based Saipem and a regional partner inked a deal this month to develop a 500-MW offshore wind farm as EPCI contractor. No project cost was disclosed. Japan and South Korea also made recent big market moves to catch up with their regional peers.

Australia's government approved new studies in March for the country’s first offshore project with a potential for 2,000 MW developed

Growth in Asia, particularly China, will account for 100 GW of the council report’s global total by 2030 (see chart). Wood McKanzie Power & Renewables, an industry economic consultant, said earlier this month that a Chinese offshore developers must commission projects by the end of 2021 to still benefit from so-called government "feed-in tariffs" before these subsidies end.

“We are standing within reach of a truly global offshore wind industry,” said Karin Ohlenforst, council director of market intelligence. She and other sector observers expect China to become the largest offshore region globally. GE Renewables said July 12 it will open a new turbine factory site in China’s emerging offshore wind hub in Guangdong province.

The challenges inherent in plying emerging markets and adapting technology for scale and new functions have expanded design firm workloads.

Erik Oostwegel, CEO of Netherlands-based Royal HaskoningDHV says, “At the moment there are hardly any [offshore wind] projects in the British part of the North Sea where we are not involved in some way.” He promotes the use of artificial islands in 40 to 50 meters of water to accommodate power current converter stations and other facilities.

Denmark’s Cowi A/S has about 120 staff focused on the sector, says CEO Lars-Peter Søbye. The market will “develop very rapidly, especially since the focus is more intense on climate change,” he says. Cowi is supporting developer Copenhagen Infrastructure Partners on international projects, particularly the 800-MW Vineyard Wind off Massachusetts—the first major U.S. project that now is moving through new permitting hurdles to start construction next year.

Design is Key

“Offshore wind has to be competitive with conventional power, and design is the key to cutting costs,” says Tim Fischer, Ramboll global wind energy director. It engineered at least two-thirds of European turbine foundations and is one of the few non-Chinese design firms with a key role in the country’s now exploding offshore sector. “Offshore wind is complex technically so design is a critical part of the whole thing,” he says.

In adapting oil-and-gas sector technology to offshore wind, engineers learned fast of pitfalls ranging from monopile corrosion and scour to grouted foundation failures and inflexible power cables, says Alistair Wood, co-founder of Wood Thilsted Partners and a former geotechnical specialist at Denmark’s DONG Energy, now Ørsted. His firm is designing Vineyard Wind turbine foundations, along with WSP.

Not appreciating the complexity of heavy turbines atop a slender, tall column contributed to early offshore installation problems, says Una Brosnan, sector business and strategy manager for the Atkins unit of SNC-Lavalin Group, which has about 200 to 250 staff assigned to global projects. “We invested a lot of time on the dynamic nature of turbines,” she says.

It apparently paid off as the firm designed the first mass-produced deep-water jacket substructures for 84 offshore turbines on the 588-MW Beatrice offshore wind project. It commissioned on time in May after three years of construction and is now Scotland’s largest such facility. The $1.2-billion array is powered by 7-MW Siemens Gamesa turbines atop steel jackets weighing up to 1,000 tonnes each in water more than 56-m deep.

Global offshore wind growth to 2030 chart

Coming Soon: Haliade-X!

Brosnan and her staff, as well as others in offshore wind design, are now preparing for what’s next as U.S.-based GE Renewable Energy readies its commercial launch by 2021 of its monster Haliade-X 12-MW turbine—with record 107-m-long blades and a 220-m rotor that can generate 67 GWh of power annually. The first prototype was connected earlier this month to a high-voltage substation in Rotterdam, Netherlands, for testing. The giant blades made their first trip outside their France-based factory, which GE acquired in 2017, for further tests in the U.K., a key intended market.

“You have to be certain that the turbine you design will perform and blades will withstand the loads,” says Derek Stillwell, GE’s North American Commercial Leader. “When you hear of a new turbine, it actually has been in process for a long, long time. We know the 12-MW beats the smaller turbines and that’s why we invested in it ... cheaper energy as a function of capacity factor.”

Joergen Scheel, vice president at rival manufacturer Siemens Gamesa, said that the firm’s new 10-MW, 193-m rotor “is pretty close to optimum today, but will not be five years down the road.”

Developers in the U.S. market welcome larger turbines that “allow us to squeeze the most capacity” in expensive ocean tracts leased from the federal government, Scott Chitwood, senior offshore engineer at Shell Offshore Wind, told an industry conference in April. Developers recently paid $135 million for each of three recent offshore Massachusetts ocean tract leases, says Ramboll's Baldwin.

But Chitwood raises risk issues in finding fabricators that can manufacture 11-m-dia steel monopiles and the Atlantic seaboard coastal space to build them.

Atkins’ Brosnan appears unfazed. “Sometimes you need that turbine in development to push the supply chain and the limits of your engineering team,” she said at the same industry event. “As a designer, it gets us thinking differently.”

Burns & McDonnell’s Appleton believes U.S. offshore wind programs will reap gains from “the largest turbines without the pain and agony Europeans experienced.”

Getting In Deep

As logistics, geology and public pushback force offshore wind farms into deeper water, sector participants are moving to cut floating turbine platform costs. Up to 80% of Europe’s offshore wind resource, about 4,000 GW, is in water deeper than 60 m.

Statoil, now Equinor, has recorded a 70% cost cut since the first floating wind farm, the 30-MW Hywind, was installed in 120-m water off Scotland in 2017, says Friends of Floating Offshore Wind, a U.K. lobbying group that includes Atkins and France’s Ideol.

“In adapting oil-and-gas sector technology to offshore wind, engineers learned fast of pitfalls ranging from monopile corrosion and scour to grouted foundation failures and inflexible power cables.”

– Alistair Wood, co-founder of Wood Thilsted Partners

Each of Hywind’s five turbines sits atop a 83-m tower founded on a 91-m tall steel tube up to 14.5 m in dia. When ballasted to 10,000 tonnes, each tube floats with nearly 80 m below water, chained down to three suction anchors. Even with weather complications and initial startup problems, the project's production performance exceeded expectations, said Leif Delp, an Equinor Wind US. floating technology expert at the New York City industry conference.

The Kincardine project, also in offshore Scotland and controlled by a Spanish construction venture, plans to install up to 50 MW of floating turbines, 8MW each, mounted on WindFloat semi-submersible platforms, that would make it the world's largest floating offshore installation.

The trade group forecasts a whole-life cost of $45 to $68 per MWh by 2030 and says 1 GW of floating wind should be built by 2025 to achieve economies of scale.

"Floating is very small still," said Scheel of MHI Vestas. But with expected demand growth, adapting turbines for it "will get more attention."

That may get realized, with floating wind the only possibility for offshore installations by California and Hawaii, two states with recently increased renewable energy goals.

South Korea also just announced a plan to start construction in 2022 of what would be a mammoth 200-MW floating project offshore of Ulsan, that has a key role for Hywind developer Equinor in joint venture with Korean oil and power companies, assuming a feasibility study supports development.

Against the Elements

Elsewhere in the developing Asia market, Taiwan’s environmental and political conditions are already challenging offshore wind developers, despite the government’s kickoff last year of a 5,500-MW program that awarded grid connections for 15 developments.

Netherlands-based Jan De Nul Group will install jacket foundations and cables in up to 55 m of water for turbines for the 376-MW Formosa 2 development, aiming for completion in 2021. COWI handled detailed earlier design for the project, in an area affected by earthquakes, typhoons and soil liquefaction—conditions not well known in offshore wind design and construction experience to date.

Danish giant Ørsted, which made a major play in Taiwan to develop the 900-MW Chang­hua projects, nearly pulled out of the market earlier this year after a permit battle with authorities over power pricing support. The projects going forward will include 112 turbines, each 8MW, to be constructed beginning in 2021.  The developer selected WSP in July to engineer the projects, which it says could power 1 million homes.

Efficiency in linking offshore wind power to onshore grids also poses design challenges as global projects move farther out to sea.

Siemens Transmission Solutions recently developed an offshore grid-access link called the offshore transformer module (OTM), a patented platform design it says is 30% lighter than conventional offshore substations, says Kevin Pearce, its U.S. business development manager for grid access technology.

The platform, using alternating current (AC) technology, operates on the U.K. Beatrice wind project and will be installed on the larger Moray East 950-MW project under construction there.

OTM can be installed by smaller ships, which Pearce says is an advantage for U.S. projects because of current federal restrictions under the Jones Act on foreign flag ships in U.S. waters.


Political and market challenges in grid design and connection for U.S. offshore wind could be even thornier than the technical ones, with decisions looming on how—or whether—offshore wind power can be delivered across state lines, and how competitive transmission should be. “There are codes and standards for design in the U.S. that are not the same as Europe,” says Robbie Gibson, renewable services director at Black & Veatch, which is helping European developers adjust.

“Transmission uncertainties need to be resolved in the U.S.” says Liz Burdock, CEO of The Business Network for Offshore Wind, a leading industry advocacy group. “We can’t build stranded assets. We need grid connection policies.”

“Transmission uncertainties need to be resolved in the U.S We can’t build stranded assets. We need grid connection policies.”

– Liz Burdock, CEO of The Business Network for Offshore Wind

The U.S.-leading 2,800 MW of back-to-back offshore wind project awards in New Jersey and New York in recent weeks will accelerate grid decision-making by federal, state and local officials.

One key question is whether offshore wind power developers should also design grid links for each project, or if transmission should be formulated in a so-called “backbone” structure to handle power collection across multiple projects and allow competition.

Ørsted U.S. CEO Thomas Brøstrom claims that approach, used in Germany, was costly and hindered market growth there. Kevin Knobloch, New York-based president of Anbaric Development Partners, which has proposed a backbone for New Jersey and New York, argues it will keep system capacity fully used.

“As markets get more mature, they will move to offshore collection and transmission systems, but no one wants to be dependent on anyone but themselves,” says Craig McKay, Tetra Tech senior vice president.

In a study released Aug. 7 of offshore wind transmission systems and grid interconnections in four European market leaders, the New York Power Authority said "planning for scale and encouraging healthy competition were key to offshore wind market growth."

U.S. offshore wind sector players also are watching whether Congress will take action soon enough on bills just introduced to extend critical federal wind farm tax incentives for both offshore and land-based wind developments, that expire on Dec. 31.

Even as the global offshore wind community wrestles with sector politics, changing technology, supply chain and workforce gaps and the race to mitigate climate change consequences, they are optimistic.

“Ten years ago, you couldn’t imagine 10-MW turbines, so anything is possible.” says Atkins’ Brosnan. “We’re getting smarter.”