Offshore wind set a record in 2021, with China boosting overall capacity alongside dayrates and utilisation, Clarksons says.

The shipbroker's research arm said on Wednesday that offshore wind produced 50.5 GW of power by the end of the year, rising 58% from 2020.

China added 16 GW, much of which came in the last two months of the year ahead of the expiry of a government subsidy programme.

"Our longer-term projections suggest that the global offshore wind sector may reach 712 farms involving over 29,000 turbines and 235 GW by 2030," said Steve Gordon, Clarksons' managing director for research.

He said the current capacity is 250 farms and 10,800 turbines.

Global wind turbine installation vessel (WTIV) utilisation averaged 83%, up six percentage points year over year.

Demand offshore China was "exceptional", Clarksons added, boosting utilisation above 90% for much of the second half.

"Rates responded, with the average dayrate assessment for third-generation WTIVs in Europe up 18% across the year, besides increases in the [construction service operations vessels or C/SOV] market also," Gordon said.

"Dayrates reportedly quadrupled off Guangdong in China in the middle of the year."

Clarksons also said there was record newbuilding investment in 2021, with more than $4bn-worth of orders placed with a focus on alternative fuel and energy-saving technologies.

Of those orders, WTIVs made up just over half, with owners placing orders for 17 worth $2.5bn, plus options for nine more.

Fifteen C/SOVs were ordered for $800m, Clarksons said, and a further 39 crew transfer vessels were commissioned.