German solar manufacturer SolarWorld AG wants to make Europe's first "green" car company, and it's looking to snap up a unit of troubled General Motors Corp. to make it happen.

SolarWorld announced Wednesday that it is offering GM €1 billion ($1.25 billion) for its Opel unit's four German auto plants, as well as its research station in Russelheim, Germany.

GM quickly denied Opel was for sale, and analysts reacted with skepticism to the offer, which sent SolarWorld shares down sharply on the Frankfurt Stock Exchange, according to news reports.

GM, Ford and Chrysler are seeking up to $25 billion from Congress to keep them from financial disaster (see Congress Comes to Automakers' Rescue - Again), but that effort has been bogged down amidst Congressional wrangling over the $700 billion bank bailout that the carmakers' rescue money was meant to come from.

Early this month, GM reported a third-quarter operating loss of $4.2 billion and said it was burning through $2.3 billion in cash per month.

GM's cash problems led Opel to meet with German officials Monday to seek as much as 1 billion ($1.25 billion) in government guarantees in case that "financial flows from the U.S. [are] no longer would be possible," said the company in a statement.

That's a sharp turnaround from April, when GM pledged to invest €9 Billion ($11.25 billion) in Opel through 2012, €6.5 billion ($8.1 billion) of it to develop new vehicles and propulsion systems.

SolarWorld said it would offer up to €250 million ($350 million) in cash and €750 million ($945 million) in credit lines for Opel, on the condition that the division undergoes a "full separation" from GM and that GM provides a compensation payment of €40,000 for each Opel worker, or about €1 billion total.    

The solar company also told Dow Jones Newswires that it wanted to restructure Opel to make electric and hybrid vehicles. That's a first-of-its-kind proposal from a company that makes photovoltaic solar cells and panels, one that would put it in competition with auto giants and startups alike (see U.K. Mini Car Designer Looks to Asian Market).

The market reacted poorly to SolarWorld's announcement, pushing down the company's shares nearly 20 percent to €13.20 in Wednesday trading on the Frankfurt Stock Exchange. The company trades under the ticker "SWV."

SolarWorld's offer comes amid a push by GM and other major automakers to move to electric and hybrid-electric vehicles. GM plans to have its hybrid Chevy Volt on sale by the end of the decade (see Chevy Volt Cleared for 2010 Production). Toyota plans to have a plug-in version of its Prius hybrid available in 2010, and Nissan wants to have electric city cars on the market by that year as well (see Is Nissan Building a Car That Charges Itself?).

GM has also discussed a possible merger with Chrysler, which has its own ambitious plans for building electric cars (see Chrysler Eyes 2010 for Launch of One of Three Electric Cars). 

SolarWorld was founded in 1998 and has production facilities in Germany, California, Oregon and Washington, and it is creating a joint venture for module production in South Korea.

In 2006, the company bought Royal Dutch Shell's American crystalline-solar-panel operations, becoming the country's largest solar-panel maker at the time. Last month it opened what it called America's largest solar cell factory in Hillsboro, Ore., with an annual capacity of 150 megawatts, bringing its total North American capacity to about 200 megawatts.