Ever-bigger turbines and floating platforms are helping to accelerate the growth of offshore wind power development in Europe, where immediate prospects remain strong, especially in the United Kingdom. But the uncertain pipeline of projects beyond 2020 could hinder continuing investment, says Pierre Tardieu, chief executive officer of the Brussels-based trade body WindEurope.

WE’s recently published 2017 review reveals Europe’s commitment for 12% more offshore generating capacity (11.5 GW) and a 20% drop in investment, reflecting falling costs. Offshore wind investment last year included $27 billion for new farms and $35 billion for project acquisition and other financial transactions.

Among European nations, the U.K. accounted for 60% of Europe’s 3,100 MW of newly installed capacity last year, according to Crown Estate, the country’s licensing authority. Germany built 34% of that total. Belgium, Finland and France shared the remaining 6% of new farms.

For the U.K., 2017 was “the busiest yet for construction,” notes Huub den Rooijen, director of energy, minerals and infrastructure at Crown Estate.

By year’s end, the U.K. had 33 active offshore farms totaling 5,826 MW, and another eight with 4,580 MW being built or committed, according to Crown Estate.

In October of last year, Norway’s Equinor (formerly Statoil ASA), with 25% project partner Masdar of Abu Dhabi, commissioned the world’s first floating wind farm 25 km off Peterhead, Scotland.

The 30 MW Hywind Scotland wind farm includes five turbines. Each sits atop an 83-meter tower founded on a 91-m-tall vertical steel tube, up to 14.5 m in dia. When ballasted to 10,000 tonnes, each tube floats nearly 80 m below water, chained to three suction anchors.

Suitable for up to 800-m water depths, the project creates “new global market opportunities,” says Irene Rummelhoff, executive vice president of Equinor’s New Energy Solutions. Up to 80% of offshore wind resources are in waters deeper than 60 m, beyond the reach of fixed structures, she adds.

Among other international floating developments, a French team led by offshore specialist Ideol S.A. late last year inaugurated a floating wind turbine.

The French installation includes a 2-MW turbine atop a 9.5-m-deep concrete pontoon with 36-m sides. Built at Saint Nazaire in western France, the turbine will soon be anchored for two years of trials in 33 m of water 22 km off the coast. It will be anchored with six semi-slack nylon ropes.

In March, Ideol agreed in principle with Acacia Renewables, a unit of Australia’s Macquarie Capital, to develop Japan’s first utility-scale commercial floating offshore wind farm, aiming to start construction in 2023. “We are now ready for the next stage: commercial-scale deployment,” says Paul de la Guérivière, Ideol’s chief executive.

While Guérivière aims for greater depths, other developers are expanding the size of generating units. Described as the world’s most powerful commercial offshore wind turbine, an 8.8 MW machine was installed in Aberdeen Bay, Scotland, this April.

Another 10 units will follow at the European Offshore Wind Deployment Centre, which is being developed by Aberdeen Offshore Wind Farm Ltd., owned by Sweden’s Vattenfall A.B.

Produced by Denmark’s MHI Vestas Offshore Wind A/S., Aberdeen’s V164-8.4 MW and V164-8.8 MW turbines will include 80-m-long blades. Each blade can power a home for a day with one rotation, according to Vattenfall’s project director, Adam Ezzamel.

Raising the stakes, GE Renewable Energy in late April signed a five-year research and development deal with the U.K. Offshore Renewable Energy (ORE) Catapult to test and demonstrate GE’s 12 MW Haliade-X unit at the research center in Blyth, England. The turbine will deploy 107-m-long blades.

Testing under controlled winds at the ORE, rather than relying on less repeatable natural conditions, will accelerate the turbine’s development, according to John Lavelle, president and chief executive of GE’s offshore wind business. Planning to invest $400 million to develop the turbine, the company hopes to start winning orders in 2021.