WASHINGTON — Republican Sen. David Vitter calls the Obama administration "reckless" for awarding billions of dollars in taxpayer subsidies for renewable-energy projects, including a $528 million loan to a now-bankrupt California solar-panel maker. But Vitter was not always so critical of the loan program.

Documents obtained by The Associated Press show that the Louisiana Republican wrote to the Energy Department at least seven times since 2009 seeking money for projects that would benefit his home state.

One of the projects he backed — for a company that makes activated carbon to reduce pollution at coal-fired power plants — has received preliminary approval for a $245 million loan guarantee.

In April 2009, Vitter urged Energy Secretary Steven Chu to approve a loan for Red River Environmental Products, saying the Coushatta, La., company could help meet a growing demand for products that help power plants comply with stricter federal regulation of mercury emissions.

"I understand the importance of accessing the domestic energy resources we have, like coal, in an environmentally conscious manner," wrote Vitter, who also backed projects for nuclear power, renewable diesel fuel and a company that makes fuel-efficient cars.

Vitter and other Republicans have pounced on the bankruptcy of Fremont, Calif.-based Solyndra, saying the White House rushed to approve a loan guarantee to the politically connected company without adequate oversight

Solyndra filed for Chapter 11 bankruptcy protection earlier this month and laid off its 1,100 employees. The Silicon Valley company was the first renewable-energy company to receive a loan guarantee under a stimulus-law program to encourage green energy and was frequently touted by the Obama administration as a model.

Vitter said in a statement Monday that he has "always pushed for an 'all of the above' energy policy, which certainly includes renewables," but added: "In the age of Solyndra, we need full transparency and accountability."

Rep. Cliff Stearns, R-Fla., who chairs a subcommittee investigating the Solyndra deal, also has backed projects promoting green jobs.

Stearns, who heads the House Energy and Commerce subcommittee on oversight and investigations, endorsed a plant that makes batteries in Jacksonville. The Saft America plant makes lithium-ion battery cells for military hybrid vehicles and solar and wind energy storage. The plant received a $95.5 million grant from the Energy Department.

Stearns and other lawmakers from Florida also backed a Florida company's bid to win a loan guarantee for biofuel refinery plant in central Florida. New Planet BioEnergy received $50 million from the Energy Department and a $75 million loan guarantee from the Agriculture Department.

Stearns said in a statement Monday that he supports clean and renewable energy and the jobs they produce, nationally and in Florida, "as long as taxpayer dollars are not put at risk."

In response to the Solyndra debacle, Vitter has co-sponsored a bill that would require an inspector-general investigation into any company that receives federal money for renewable energy and then goes bankrupt.

Republican Rep. Lamar Smith of Texas, chairman of the House Judiciary Committee, wrote to Attorney General Eric Holder on Monday that an outside lawyer is needed to probe the loan approved for Solyndra.