UPDATE 1-Orsted dives 17% after US impairments; Trump adds to uncertainty

Updates throughout, adds valuation, Trump quote, detail in paragraphs 2, 6-8, 11

By Stine Jacobsen

COPENHAGEN, Jan 21 (Reuters) - Shares in Orsted ORSTED.CO plunged 17% on Tuesday after it posted an impairment charge on delays to a U.S. offshore project, a sector facing new uncertainty after President Donald Trump withdrew government support for wind power.

Orsted posted a fourth-quarter impairment charge of 12.1 billion Danish crowns ($1.69 billion) late on Monday due to factors including Sunrise Wind, which is expected to be the largest U.S. offshore wind project once completed.

"This impairment, and especially the continued construction challenges, are very disappointing," CEO Mads Nipper told investors on Tuesday.

The former oil and gas company has struggled to unleash the potential of the U.S. offshore wind market and been forced to book several impairment charges. Its shares have plunged 84% since peaking in 2021.

"It is a very new market with a completely nascent industry and supply chain," Nipper said when asked about the firm's struggles.

Once a green investor favourite, Orsted's market value stood at $15.08 billion on Tuesday, down from over $18 billion at Monday's close and a peak of $93.9 billion in Jan. 2021, according to LSEG Datastream.

Its woes reflect the changing fortunes of wind power globally as soaring costs, delays and limited supply chain investment prompt investors to reassess the speed of energy transition.

Further complicating Orsted's ambitions in the United States, U.S. President Donald Trump on Monday suspended new federal offshore wind leasing pending an environmental and economic review.

"We're not going to do the wind thing. Big, ugly wind mills. They ruin your neighbourhood," Trump said.

Orsted declined to comment on the potential impact of the U.S. review.

"We see higher risks for the U.S. offshore wind industry given President Trump's policies against the industry, including the risk of no further U.S. offshore wind development over the medium term," Barclays analysts wrote in a research note.

(Reporting by Stine Jacobsen in Copenhagen, additional reporting by Amanda Cooper in London; editing by Terje Solsvik and Jason Neely)

((stine.jacobsen@thomsonreuters.com; +45 2156 90 10;))