The company has also agreed to make turbines for Cape Wind, which could become the country’s first offshore wind farm. More than a decade in the making, it has faced lawsuits and stiff opposition from Cape Cod residents who say the spinning machines will spoil pristine views and raise the price of electricity.

Other companies are benefiting from the new orders, too: Vestas said on Tuesday that it would reach its second-highest peak in sales in the United States and Canada this year since it entered the market in 1981, with recently announced equipment orders for projects in Texas and Oklahoma.

Opponents of the credit campaigned against a renewal all fall. They include some fiscal watchdogs worried about the cost. But the bulk of the opponents are mostly generators of other forms of energy, who say that by subsidizing wind, the government is adding supply to the market in a way that depresses prices for electricity, cutting the revenues of other generators and, in some cases, driving them out of business.

The subsidy “is grossly distorting the marketplace,” said Don Nickles, a Republican who represented Oklahoma in the Senate from 1981 to 2005 and is now a consultant on energy policy. The problem, he said, was that the credit was very large relative to the wholesale price of electricity. It is occasionally infinitely larger. During the late-night hours when overall electric demand is low and wind production is high, the value of a kilowatt-hour on the open market is sometimes zero or below. Wind generators collect the credit regardless.

Mr. Nickles, who was a senator when the first production tax credit was passed, said that it was meant to be an incubator for a fledgling industry. Now, he said, “This child is ready to go to college.”

Some of the economic logic behind wind energy no longer exists. In most places, every additional megawatt-hour generated by a wind machine means that a plant running on natural gas could be dialed back. When natural gas prices were high, the savings could be significant. But natural gas prices have dropped with the new supplies brought on by hydraulic fracturing, or fracking. So the savings have shrunk.

The production tax credit for wind energy has passionate opponents in the nuclear industry. This is because in about half the country, electrically speaking, the wholesale price of electricity is set by auction, and when there is oversupply, prices drop. Sometimes they drop below zero.