House Energy and Commerce Chairman Fred Upton had been quietly investigating a loan guarantee to the now-bankrupt solar panel company Solyndra since February, reviewing tens of thousands of pages of documents and carefully plotting the rollout of some of the more damaging revelations.

But when the headlines started hitting in late summer, the Michigan Republican soon had company.

On Sept. 19, House Oversight and Government Reform Chairman Darrell Issa (R-Calif.) sent a letter to a top lawyer for President Barack Obama requesting internal White House communications about Solyndra all the way back to the first day of the administration.

“[T]he Committee respectfully requests that you provide … [a]ll documents and communications between and among personnel in the Executive Office of the President (EOP), including, but not limited to, the White House Office, and personnel at OMB, DOE, and the Council on Environmental Quality (CEQ), relating to the approval of the Solyndra loan guarantee,” the letter said, going on to request a similar set of documents on a series of related topics.

A little more than two weeks later, on Oct. 5, Upton and Rep. Cliff Stearns (R-Fla.), chairman of the Energy and Commerce Subcommittee on Oversight and Investigations, sent their own letter requesting essentially the same thing.

“We ask that you provide … [a]ll communications among White House staff and officials relating to the $535 million loan guarantee to Solyndra by the Department of Energy between January 20, 2009 and the present,” the letter said.

The request, a logical next step in their investigation, was expected from Upton and Stearns.

But Democrats close to the Obama administration were surprised that Issa had jumped into the fray a full seven months after Upton and Stearns started investigating.

“Issa hadn’t cared at all about Solyndra until it started raining headlines, and then suddenly it troubled him deeply,” said one Democrat familiar with the investigation.

Two sources off Capitol Hill say the incident has caused friction between Upton and Issa, and insiders call the duplicative requests unusual.

“It has caused some significant tension between the committees,” said a lawyer familiar with both panels. “Energy and Commerce is doing a great job on this investigation. Issa’s been doing a great job on Fast and Furious. You don’t need two committees working on the same investigation.”

Don Goldberg, a partner at Bluetext and a former member of President Bill Clinton’s crisis management team, said that on an investigation as high-profile as Solyndra, it is “highly unusual” for the two committees to have submitted a request for the same documents.

“It shows that they’re not really coordinating or communicating,” Goldberg said.

Publicly, both sides praise each other.

“The Energy and Commerce Committee has done groundbreaking work exposing the Solyndra scandal. Chairman Issa has praised Chairman Upton and Chairman Stearns for their committee efforts,” Issa spokesman Jeffrey Solsby said.

“There is no shortage of questions to be answered regarding the Obama administration’s bungling of Solyndra, and every single Member of Congress should be lining up to get those answers. We are working with the Oversight and Government Reform Committee to get to the bottom of this fiasco, and we believe everyone can play a constructive role examining this failed gamble from different angles as taxpayers now find themselves on the hook for this half billion dollar bust,” said Sean Bonyun, an Energy and Commerce spokesman.

The conflict doesn’t appear to have attracted the attention of GOP leaders, with a leadership aide telling Roll Call, “I guess the White House can photocopy those documents” when told of the duplicative requests.

Issa said in his Sept. 19 letter that his request relates to a broader investigation of “improper influence of political appointees on the official business of the U.S. Government.”

“The Oversight Committee’s work is focused on understanding what took place at the Department of Energy as well as other examples throughout the federal government where similar abuses may have occurred,” Solsby said.

The White House formally responded to Upton’s request in an Oct. 14 letter, saying it would continue production of communications between White House officials and three federal agencies but would not supply internal communications among White House officials — the type of documents both Issa and Upton are asking for.

Solsby said the White House separately told Issa that the administration would be providing Issa the same documents it is providing Upton.

In the 112th Congress, there are other examples of Issa becoming involved in Energy and Commerce-led investigations.

On Jan. 20, Upton and Stearns sent a letter to the Department of Health and Human Services requesting documents regarding the waiver process for the new health care law. Issa followed that with a similar request Feb. 10.

On Feb. 24, Upton and Rep. John Shimkus (R-Ill.), chairman of the Energy and Commerce Subcommittee on Environment and the Economy, sent a letter to the Energy Department asking for information about proposals to dispose of nuclear waste at Yucca Mountain, Nev. On March 11, Issa said in a letter to the chairman of the Nuclear Regulatory Commission that his panel “is conducting an investigation into the termination of the Yucca Mountain Project.”

Part of the reason for some of the overlap is the oversight panel’s jurisdiction. House rules say the committee “may at any time conduct investigations of any matter.”

A question going forward is how each chairman will respond to the White House telling Upton and Stearns that it won’t fulfill their request.

Both Issa’s Sept. 19 letter and Upton’s Oct. 5 letter are requests — not subpoenas — for documents. Either could issue a Congressional subpoena compelling their release.