The Obama administration is cooperating with Congress in the investigation of a half-billion dollar Energy Department loan guarantee to a now-bankrupt alternative energy company, but a response to potential subpoenas is premature, a top adviser to President Obama said Sunday.

Obama adviser David Plouffe said the administration takes "very seriously" the failure of California-based solar power company Solyndra, which received $535 billion from the federal government, and has appointed a former assistant treasury secretary to Tim Geithner to review the entire loan program that permitted the arrangement. A public report on the now-defunct program is due at the end of the year. 

"I'm not going to comment on a subpoena that's not been issued," Plouffe told NBC's "Meet the Press." "We've already produced 70,000 pages of documents. We are cooperating with the congressional committees. ... We take very seriously the fact that one of these loans did not work. That's why we appointed Herb Allison who did a bunch of the investigative work on (the Troubled Assets Relief Program) part to look at this.

"By the way, this is important to look into. We'd like to see as much passion in Congress for creating jobs as we do with some of these issues," Plouffe added.

Several committees have begun investigating how Solyndra was able to get a repackaged loan guarantee earlier this year when its financial problems were already well-recognized by the Energy Department. 

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On Thursday, the House Energy and Commerce Committee will vote whether to subpoena the administration for additional information. Committee Democrats have suggested the whole investigation is aimed at merely benefiting the oil industry and trying to embarrass Obama.

But at a hearing of the House Energy and Commerce oversight subcommittee earlier this month, two Treasury Department officials testified that they'd never seen a case where private money was prioritized ahead of taxpayer money in the way the Solyndra loan was structured. 

A series of memos released in August showed Treasury officials warning that a later restructuring of the loan may be illegal. Mary Miller, an assistant treasury secretary, said she told a top White House budget official that she advised that any proposed restructuring be reviewed by the Justice Department before it was approved, but to her knowledge that never happened. 

But the Energy Department contends that the restructured loan was legal, and the White House argued that it needed to be done to save the 1,100 jobs Solyndra provided. The company closed its doors in August, releasing all of its employees.

Meanwhile, Plouffe rejected the suggestion that the loan was allowed to go through because of the connection between Solyndra and big money contributors to the Obama campaign.

"Absolutely not. These decisions about the loan program were made by career officials at the Department of Energy on the merits," Plouffe said.

At least one adviser working in the Energy Department program, however, warned the administration that the loan could be an embarrassment, and key investors in Solyndra, like George Kaiser, who was also a bundler for Obama's 2008 presidential campaign, is in line to be paid ahead of the government, according to the contingent bankruptcy terms approved by the Energy Department.

Plouffe, who said solar and other alternative energies are critical to the future, especially if they create high-paying jobs, argued that the loan program wasn't just a project of the Obama administration but was supported by President George. W. Bush as well as Republicans who are now criticizing it. 

He added that the U.S. has "to do everything we can" to compete globally in the energy sector. 

"We have to win this race. You know. We -- if we don't win the clean energy race, in terms of technology, innovation and jobs, and cede it to other countries we're not going to have the center and we need this. It would be like us ceding the automotive race or the Internet or computer race," he said.