(Adds quotes from experts, adds background)
COPENHAGEN, Dec 21 (Reuters) - Denmark's Vestas, the world's top wind turbine maker, said on Thursday it was pleased the final U.S. tax bill retained production tax credits for wind energy projects, after concerns over the bill had sliced almost a quarter off its share price.
Earlier versions of the bill would have removed the credits, a move that the renewable energy industry said would threaten $50 billion in planned investment in wind energy projects in the United States.
The $1.5 trillion tax bill, which won final approval from Congress on Wednesday, retains a previous plan to gradually phase out the production tax credits (PTCs) by the end of 2019.
"We are pleased that the approved tax bill retains the PTC phase-out," Vestas said, adding it expected the bill would "enable further growth of the wind energy industry."
The final U.S. tax bill retains the production and investment tax credits for wind and solar energy that have spurred investment in these industries. It also eliminates the alternative minimum tax, which would have reduced the value of those credits.
The U.S. renewable energy industry has expressed relief that the compromise Republican tax bill preserves the tax credits.
The bill includes the Base Erosion Anti-Abuse Tax (BEAT), which was intended to prevent multinational companies from abusing the tax code, but has worried the renewable energy industry because it would limit the ability to claim a portion of production tax credits, which are key to raise investments.
But, the final bill made changes to a more severe Senate proposal by allowing the credits to offset up to 80 percent of the BEAT tax.
Vestas warned on Nov. 9 it faced lower future profitability and possible subsidy cuts that could hit U.S. sales, sending its shares tumbling by nearly 20 percent. The shares have recovered slightly since then, but were trading down 0.3 percent on Thursday.
Tax equity currently accounts for 50 to 60 percent of total capital invested in wind projects, according to law firm Norton Rose Fulbright, and some uncertainty still remains as to how the marketplace will react to the BEAT provision.
"Many project developers have to get back to their spreadsheets to look at how the new tax legislation impacts the project economy and safety of their pipeline of wind projects," said Sydbank analyst Jacob Pedersen in a research note.
Chief Executive Michael Rucker, of solar and wind developer Scout Clean Energy, said the BEAT provisions included in the bill would "continue to drive uncertainty in our sector, and could cost many communities crucial investments and jobs."
Vestas is the most exposed turbine maker to the U.S. market, where it overtook General Electric last year in installed capacity.
Other peers operating in the U.S. include Siemens Gamesa and Germany's Nordex.
Reporting by Stine Jacobsen and Jacob Gronholt-Pedersen; Editing by Adrian Croft