Shares of thin-filmsolarmanufacturer First Solar (NSDQ: FSLR) climbed more than 2 percent to close at $291.99 per share Wednesday after the company posted first-quarter earnings that beat analyst expectations and upped its sales guidance for the full year.

First Solar posted first-quarter net income of $46.6 million, or 57 cents per share, up more than ninefold from $5 million, or 7 cents per share, for the same quarter a year ago.

Quarterly revenues fell 1.94 percent to $196.9 million from $200.8 million in the fourth quarter of last year, but more than doubled from the $66.9 million in sales in the year-ago quarter.

Wall Street had expected earnings of 47 cents per share on revenue of $183.6 million, according to Thomson Financial.

Also on Wednesday, Tempe, Ariz.-based First Solar raised its revenue forecast to between $975 million and $1.05 billion for the year. Previously, the company had expected sales of between $900 and $950 million.

The company's guidance boost is largely due to the ramping up of production at its Malaysian plant, said Sanjay Shrestha, a senior analyst at Lazard Capital Markets, in a research note Wednesday.

With its cadmium-telluride films, which convert sunlight into electricity without using precious silicon, First Solar has become a Wall Street darling of sorts over the past year.

In February, the company saw its shares jump more than 30 percent after posting a fourth-quarter income that was seven times higher than the year-ago quarter (see First Solar Rides High).

One reason investors love First Solar is that it’s one of a very small group of thin-film companies to reach large volumes (see Thin Films Lead U.S. Solar Production).

First Solar's annual capacity is about 300 megawatts, according to the company's annual report, making it by far the largest thin-film manufacturer in the world. The company expects to reach 484 megawatts of capacity this year and more than 1 gigawatt next year.

But other thin-film companies certainly are trying to give First Solar some competition.

Among others, Nanosolar and Global Solar have begun producing copper-indium-gallium-diselenide films, and Heliovolt – which also is pursuing CIGS technology -- is building its first factory (see Nanosolar Begins Production, Competition for First Solar? and Heliovolt on Nanosolar’s Heels).

OptiSolar, of Hayward, Calif., also is gearing up with big solar project plans for its silicon-based thin films. On Wednesday, Greentech Media reported that the solar parks OptiSolar has planned in Ontario and California alone account for more than 700 megawatts of solar capacity (see Can OptiSolar Make Thin-Film Dreams Real?).

Yet, as companies like Moser Baer plan to invest $1.5 billion in thin-film solar, Jesse Pichel, a senior research analyst at Piper Jaffray, doesn't see any threats to First Solar, at least in the near term.

First Solar, which last year said its cells averaged 9 percent efficiency, meaning they convert 9 percent of the sunlight that hits them into electricity, told Pichel earlier this month that their cells averaged 10.6 percent at the end of the fourth quarter.

"We have reasons to believe that some of [First Solar's] panels might be measuring significantly higher," Pichel wrote in a research note Tuesday.

For comparison, Global Solar’s CIGS cells average 10 percent efficiency, while traditional crystalline cells frequently have efficiencies between 12 and 15 percent.