WASHINGTON — Four Democratic senators Wednesday implored the Obama administration to stop spending federal stimulus dollars on renewable energy projects whenever the bulk of solar cell and wind turbine manufacturing is done overseas.

The group — led by Sen. Charles Schumer, D-N.Y., — also is pushing legislation to ensure that future stimulus spending flows only to renewable power projects that create mostly U.S. jobs.

"It is a no-brainer that stimulus funds should only go to projects that create jobs in the United States rather than overseas," Schumer said. "These wind projects have a lot of merit, but the manufacturing should be happening here, not in China."

At issue is a $3 billion grant program created by last year's stimulus bill that aims to spur deployment of wind farms, solar power installations and other renewable energy facilities. The grant program allows developers who forgo investment tax credits to apply for Energy Department grants covering 30 percent of the total project cost.

Schumer is angry about a planned wind farm in West Texas — a $1.5 billion collaboration involving Austin-based Cielo Wind Power LP, China's Shenyang Power Group and the private equity firm U.S. Renewable Energy Group. Schumer said it made his "blood boil" that developers may seek federal tax credits that would defray 30 percent of the project cost, even though the 600-megawatt facility is expected to rely on Chinese-made turbines.

Cappy McGarr, a managing partner of U.S. Renewable Energy Group, insisted that at least 70 percent of the wind turbines in the project would be made domestically with American steel.

"The vast majority of jobs created as a result of the 600-megawatt wind farm will be located in the United States and done by American workers," McGarr said.

Schumer was joined by Sens. Robert Casey, D-Pa., Sherrod Brown, D-Ohio, and Jon Tester, D-Mont., in asking Treasury Secretary Timothy Geithner for a moratorium on clean-energy grants until Congress passes legislation that would require recipients to do most of their work within the U.S. Any suspension in the program "would cause immediate layoffs of American workers at American manufacturing plants," said Energy Department spokeswoman Stephanie Mueller, adding that the program has "put Americans to work" by luring $10 billion in foreign investments in U.S. projects.

"The best way to stimulate our manufacturing base is to stimulate demand for wind turbines in America, since manufacturers tend to locate where the demand is," Mueller said.

Wind industry leaders warned that suspending the grants would jeopardize projects nationwide and could cause developers to cancel other ventures. The grants at issue only apply to projects under construction by the end of the year.

The nonpartisan Investigative Reporting Workshop at American University reported recently that foreign companies have secured 79 percent of the $2 billion in grants that have been committed under the renewable power program, even though related manufacturing may be done in the U.S.

The Obama administration points to the example of Iberdola, a Spanish firm, which began construction on a stalled wind farm project in Pontiac, Ill., thanks to stimulus grants. The turbines come from another Spanish firm, Gamesa, which is using an abandoned U.S. Steel plant in Pennsylvania to make them. Administration officials say Iberdola has committed to investing an additional $6 billion in U.S. projects as a result.