Energy secretary assailed for repeatedly claiming to have had no real-time knowledge of key events in firm's collapse

The US energy secretary, Steven Chu, put up a strong defence of the administration's loan to a failed solar company on Thursday, but the Nobel physics laureate's own wisdom and judgment was put under the microscope in a hostile congressional hearing.

In five and a half hours of gruelling testimony to the house energy and commerce committee, Chu was assailed for repeatedly claiming to have had no real-time knowledge of key events in the collapse of Solyndra, which went bankrupt in August after receiving $535m in government loans.

"I hope you didn't leave your brains at the door," Morgan Griffith, a Republican from Virginia, told Chu.

The energy secretary, who remained unflappable throughout the barrage, was just as unyielding on the question of an apology for the failure of Solyndra and the loss of taxpayer funds.

In his testimony Chu refused on multiple occasions to apologise for the Solyndra debacle – although he did go so far as to describe the company's collapse and the loss of US public funds as "extremely unfortunate" and "regrettable".

Asked whether he would still approve such a loan today, Chu said: "Certainly knowing what I know now, we'd say 'no', but you don't make decisions fast-forwarding two years in the future and then go back. I wish I could do that."

By the end of the day Chu had deflected Republican attempts to cast the entire clean energy industry as a pay-off for Democratic donors. "I want to be clear: I did not make any decision based on political considerations," he said. But he was left exposed on the question of his own general competence.

On question after question, to the Republicans' frustration, Chu claimed to have had knowledge of key decisions.

"I'm aware of it now" was all he could offer. It was a phrase Chu deployed more than a dozen times and it had the effect of making him the target of Republicans, rather than the White House.

Among other things, Chu claimed ignorance of documents warning Solyndra was a bad bet in early 2009 – before the loan was awarded. He said he had never heard of George Kaiser, the Democratic fundraiser who was the main investor in Solyndra.

Republicans did not buy it. "Everybody and their dog at DOE knew who he was and what he was involved in," Joe Barton of Texas said.

The cumulative effect of Chu's responses was to deflect the Republicans away from their charge that the administration gave the loan to Solyndra as a favour to Kaiser. "I don't see from today's hearing that there was a smoking gun here," Lee Terry, a Republican member of the committee from Nebraska, said in an interview.

But that put Chu in the firing line. "The main impression I got today was that he wasn't as involved in the process as we assumed he was. I don't know if he was just a figurehead, but I assumed like everybody else that he was actually involved in the decisions," Terry said. "He just seems … detatched."

Other Republicans went farther. Cliff Stearns, who has led the Republican charge on Solyndra as chair of the committee's investigations wing, told the hearing that Chu deserved to be fired.

"I just think he has failed the test," Stearns said.

Chu refused on multiple occasions to apologise for the Solyndra debacle – although he did go so far as to describe the company's collapse and the loss of US public funds as "extremely unfortunate" and "regrettable".

The five and a half hour hearing was extraordinarily long by the usual congressional standards. As a comparison, BP's Tony Hayward was grilled for just half that time at the height of the oil spill disaster in the Gulf of Mexico.

It was also ill-tempered. Republican members of the committee on several occasions cut off Chu's answers or, as he wearily complained after four hours of testimony, trod over the same old ground. "These questions are going over and over and over," he said.

The White House has supported Chu in public for the duration of the scandal. But the energy secretary has been damaged by an email released in response to demands from Stearns, which shows other administration officials expressing doubts about Solyndra's viability – even in early 2009 before the loans were finalised.

He was also hurt on Thursday by his justification for extending further loans to the company as it was failing, and his admission that he could not guarantee there would be no further collapses among the three dozen or so other clean energy companies that also got government loans. "I can't promise you there won't be another," he told reporters.

Chu also failed to squash the Republicans' charge that he broke the law with a restructuring agreement that put private investors ahead of taxpayers if Solyndra was forced into liquidation.

An aide to Chu, in an email sent out after the hearing, rebutted the claim. "Secretary Chu relied on the thoughtful, thorough legal analysis of the career lawyers in the department's loan program," Dan Leistikow, the communication chief, wrote.

Chu, meanwhile, ended the day with the same quiet defiance with which he fended off Republican attacks. At the end of his grilling, he told reporters America had no choice but to push ahead on solar energy – or else give up the field to China. "America faces a simple choice: compete or accept defeat," he said.

(By Suzanne Goldenberg, The Guardian, 18/11/2011)