The U.S. Department of Energy learned in December that Solyndra was violating its federal loan deal, but the agency changed the loan terms to allow the solar company to continue receiving taxpayer funds, federal officials confirmed Wednesday.

Executives at Solyndra, which had been awarded a $535 million government-backed loan to spur its solar-panel production, confided to the Energy Department late last fall that the Fremont, Calif., company was running out of money and at risk of liquidating.

The company was unable on Dec. 1 to make its first $5 million payment into a special reserve fund, which was required under the loan terms and designed to help protect taxpayers.

Congressional investigators have questioned why the Obama administration agreed to help the company in late 2010 when it was warned that the firm was at risk of collapse. Internal e-mails show federal reviewers initially estimated they could save the taxpayers as much as $168 million by letting the company go under in December 2010, rather than resuscitating it and allowing it to draw down more federal money.

Energy Department spokesman Damien LaVera confirmed Wednesday that the agency knew Solyndra had violated the loan terms but agreed to change the requirement to help Solyndra. The agency originally required that Solyndra make six installments of $5 million each, starting in December, to create a $30 million cash cushion for problems.

Solyndra closed its business Aug. 31, then filed for bankruptcy protection. Its closure laid off 1,100 workers without warning and left taxpayers on the hook to repay its half-billion-dollar loan. Days later, the Energy Department’s Office of Inspector General and the Justice Department executed surprise search warrants at the company’s headquarters as part of a criminal probe.

On Wednesday, the Energy Department approved two loan guarantees worth more than $1 billion for solar energy projects in Nevada and Arizona, two days before the expiration date of the program, the Associated Press reported. Energy Secretary Steven Chu said the department has completed a $737 million loan guarantee to Tonopah Solar Energy for a 110 megawatt solar tower on federal land near Tonopah, Nev., and a $337 million guarantee for Mesquite Solar 1 to develop a 150 megawatt solar plant near Phoenix.

The Solyndra matter has turned into a political issue for the Obama administration because some of the principal investors in the start-up were linked to a major Democratic Party fundraiser, Tulsa billionaire George Kaiser. Kaiser has said through a spokesman that he had no involvement in the federal loan.

LaVera said the Energy Department approved a restructuring of Solyndra’s loan terms because the agency “thought it gave Solyndra a fighting chance to survive and the taxpayers their best chance to recover their loan.”

A House subcommittee probing the loan has questioned the decision. Obama administration officials testifying at a Sept. 14 hearing did not disclose that they had removed the requirement that Solyndra create a cash reserve.

By the end of 2010, Solyndra had withdrawn an estimated $460 million of its loan, approved and guaranteed by the Energy Department. With the restructuring, which some federal officials said in internal e-mails they considered highly risky, it was able to tap an additional $67 million.

The chairman of the House Energy and Commerce investigations subcommittee, Rep. Cliff Stearns (R-Fla.), said: “Even when Solyndra was out of cash in December 2010, DOE turned a blind eye to reality, doubling down on a bad bet that further put American taxpayers at risk. . . . ”