Solar-power stocks lose place in sun

— -- Solar-power stocks, among the brightest spots on Wall Street all of last year, are beginning to short-circuit.

After doubling, tripling or more in 2007, shares of leading companies that make the pieces and parts needed to generate solar power are showing serious signs of trouble.

"These (solar) stocks have had a bubble mentality with them," says Mark Bachman, analyst at Pacific Crest. "It's not the same as the Internet bubble, … but when you look at the valuations, they're frothy."

It's not that investors have given up on clean energy. Demand around the world is strong as governments have decided to subsidize the technology.

But investors are having serious second thoughts about their optimism for several other reasons:

•Falling price for crude oil.

Oil's falling price this year is scaring away solar investors, says Jonathan Hoopes, analyst at ThinkEquity Partners.

Why? Investors generally use the price of oil as a benchmark of conventional energy prices and a gauge of how viable solar is. When the price of oil surges, for instance, investors figure more homes, businesses and utilities will be willing to pay the high upfront costs to install solar-power-generation capabilities, Hoopes says.

The link between solar stocks and the price of oil is uncanny. Solar stocks soared in 2007 as the price of a barrel of oil climbed 63% from the end of 2006 to Jan. 2, the first trading day in 2008. The price of a barrel of oil closed just 38 cents a barrel below the important $100 mark on Jan. 2.

But oil has been struggling in 2008, which has prompted some investors to scurry out of solar stocks. This month, the price of oil has fallen more than 7% to $88.55 a barrel, based on electronic trading Monday, according to Bloomberg. Floor trading was closed for the Martin Luther King Jr. holiday.