Last summer, wind turbine manufacturers couldn't make parts fast enough to meet demand. Now, industry executives say, financing has all but disappeared because of the economy, causing some planned projects to be put on hold. Unless there's a robust economic rebound, or the government steps in, they say, construction of wind turbines nationwide will be set back, and the companies that make turbine parts could be forced to cut jobs.

That would be especially bad for Massachusetts, where state officials recently detailed a goal to have 2,000 megawatts of wind power capacity installed by 2020 - more than 300 times the current level. About 900 megawatts of wind power capacity are in the planning stages.

The dim outlook, included in a new report from the American Wind Energy Association, a trade group, follows a record year for wind power business. The industry now employs about 85,000 people nationwide, up from 50,000 a year ago.

According to the association, wind projects completed in 2008 add up to more than 8,300 megawatts of generating capacity - enough electricity for 2 million homes - increasing the nation's total capacity by about 50 percent.

But maintaining that momentum will be a challenge because of the recession, said the association's chief executive, Denise Bode. Some orders for wind turbines are being canceled, Bode said, and unless the economy rebounds soon, there could be a 50 percent drop in projects. That would effectively set the industry back to where it was three years ago, she said.

"I think any of these projects are in danger of being stalled if they don't have the capital to build them," Bode said.

Marty Aikens, a business agent at the International Brotherhood of Electrical Workers Local 103 in Dorchester, said union members - who often work on wind turbine projects - have reported a decline in wind power-related work.

"There are probably three or four projects that can't get off the ground because of financing," Aikens said. "People are scared to make the big commitment financially."

State officials said it would be unrealistic to expect wind projects here to be immune to the recession.

"I think that everything we do in state government has the potential to be adversely affected by the economic conditions," said Ian Bowles, secretary of the Executive Office of Energy and Environmental Affairs. Bowles said his office is still pushing for wind projects that are planned or underway to reach completion.

Local industry leaders, meanwhile, said they are monitoring the situation and making adjustments to their long- and short-term plans.

"Clearly the pace of construction and turbine acquisition is going to go to sleep for 18 months, there's no question about that," said Steve Kropper of WindPole Ventures, a wind power development firm in Boston.

Kropper said the economy recently prompted WindPole to switch its focus from lining up financing to pushing forward with existing projects that have secured financing.

Still, Kropper said he and his peers are optimistic the state's environmental goals - to reduce greenhouse gas emissions through increased renewable energy use - and an anticipated injection of aid from the federal government will help the wind industry keep growing.

"We all joke Obama gets up in the morning, he thinks, 'Wind!' and then he goes to brush his teeth," Kropper said, referencing President Obama's stated commitment to increase use of solar, wind, and water power.

Bode, of the American Wind Energy Association said, the industry hopes federal officials extend the timeline for a tax credit that pays wind project owners about 2 cents for every kilowatt hour they generate. The credit is now set to expire at the end of the year.

Also, she said, the organization wants the tax credit to be temporarily modified so that developers can seek funding from the government instead of private sources, which have largely stopped lending.

"We're hopeful," Bode said, before adding, "You never know what's going to happen."

Meanwhile, at least two Massachusetts wind projects in the works, including an upgrade to the Princeton Municipal Light Department's wind farm, remain on track.

"Financing-wise, we're set," said Jon Fitch, general manager of the light department in Princeton.

And for other projects that have financing and are about to enter the construction phase, there is good news: The slowing demand for turbines has made it easier to get one immediately, usually at a discounted price. Just last year, the wait for some turbine parts was 18 months or longer.