Stock prices for a number of solar industry companies surged Monday after LDK Solar and SunPower made major announcements.

After LDK Solar (Nasdaq:LDK), a Chinese solar photovoltaic panel manufacturer, announced that its financial earnings surpassed expectations its stock price soared more than 18 percent to $12.33 a share.

Similarly, California-based SunPower (Nasdaq:SNPWRA) stock shot up more than 8 percent to $14.62 after it announced that it would be installing more than 700 megawatts of solar photovoltaic panels with Sun Edison in Southern California by 2016.

“These stocks are really driven by the news flow that they put out there,” said Adam Krop, a stock analyst with Ardour Capital Investments.

These big pieces of good news were just what investors were waiting for, Krop said. The solar industry saw depressed stock prices through most of 2010 and investors were waiting and expecting to see the industry turn around.

“The industry was bound to begin to recover,” Krop said. “With this positive news, you’d expect to see positive movement in the market.”

While both LDK and SunPower have made numerous positive announcements over the last year, today’s news was bigger, Krop said.

SunPower announced in late November that it would work on a more than 200-megawatt solar ranch, and the announcement didn’t make much of an impact on the stock price.

But a 711-megawatt solar development, even though it’s going to be spread over the next five years, is a good indicator of the company’s financial health, Krop said. It’s a huge project.

Along with LDK and SunPower, whose share prices soared as a direct result of positive news announcements, dozens of other solar industry companies saw big gains on Wall Street Monday.

“Unfortunately, we’re still in a place where these stocks tend to move as a group,” Krop said of solar industry stocks.

SunPower’s gain was the largest in the 100-member WilderHill New Energy Global Innovation Index. But six of the 10 companies with the biggest gains in that group today are solar companies.

As the solar industry continues to grow, solar companies will be popular investments, Krop said.

“I’m sure it is going to continue, but they’re not all long-term winners,” he said. “You still have to pick the right companies.”

Image courtesy of googlestocks.