Suntech Power Holdings Co. (NYSE: STP), which saw its stock surge some 150% in 2007, didn't have such a good 2008 so far with its stock plunging about 44% year-to-date. But since setting a 52-week low of $28.19 on March 22, the stock has rebounded nicely, up over 55%. Roller coaster or what?!

Well, today, the maker of photovoltaic cells and modules said first-quarter earnings more than doubled on 76% higher revenue. Earnings reached $55.8 million, or 33 cents an American depositary share, beating analysts estimates of 28 cents. Revenue reached $434.5 million. Gross margins also expanded nicely and Suntech reiterated revenue estimates for 2008.

Early in the morning, STP shares jumped over 7% in premarket trading in response to the report but have not kept this up. Shares are now trading at $45.73, down over 1%, probably declining with the rest of the sector following Goldman Sachs's downgrade of Solarfun (NASDAQ: SOLF) to Sell from Neutral. SOLF shares are down over 18% taking LDK Solar (NYSE: LDK), Trina Solar (NYSE: TSL) and Canadian Solar (NASDAQ: CSIQ) down with it -- 5%, 8% and 13% respectively, to name but a few.

Suntech Power has long been a favorite of mine in a sector that has new companies popping up like mushrooms after the rain. With very little barrier to entry and with rising cost of raw materials -- mainly polysilicon, which was also in short supply -- being one of the largest companies in the sector can have its advantages. Besides, I'm always more skeptical when a sector is so hot. Of course, anyone who doesn't think alternative energy, and solar in particular, isn't going to take a larger share in our lives as oil prices move up, they live in a different reality. Therefore, a solid solar company would be the play for me.

Despite delivering solid results, Suntech said its solar cell production capacity doubled to 540 megawatts at the end of the first quarter, and it predicts it will reach 1 gigawatt of capacity by the end of the year. I hope the new output will grow enough to satisfy the surging demand, as STP would certainly want to capitalize on the rising prices and demand for its product.