SunPower ( SPWRA) swung to a loss in the first quarter. The San Jose, Calif.-based solar panel maker lost $2.5 million, or 6 cents per share, compared with a profit of $14.7 million, or 15 cents per share, a year ago. Excluding items, the company earned 5 cents a share. Revenue fell 22% to $214 million from $274 million a year ago. Analysts polled by Thomson Reuters were expecting EPS of 24 cents on revenue of $269 million. "The first quarter of 2009 was the most challenging quarter we've seen since SunPower went public in 2005," said Tom Werner, SunPower's CEO, in a release Thursday. "Our quarterly performance was impacted by seasonality, the continuing effects of the credit crisis and difficult economic conditions. Despite these headwinds, we were able to deliver strong gross margins in our components business and positive non-GAAP net income. "We have responded to current market conditions by moving to a demand-driven manufacturing model and reducing our planned operating expenses to align with our adjusted revenue outlook," he said. "Our recent announcements with FPL Group, Exelon ( EXC) and Xcel are representative of the range of opportunities in our utility and power plant business pipeline. Looking forward, we see positive trends emerging in a number of market segments, including the rooftop, distributed power plant and utility markets that give us confidence that we are well positioned for growth in the second half of 2009, 2010 and beyond." SunPower shares were trading down 6.7% after hours to $24.20.