Company: Suntech Power Holdings Co., LTD.

(Reuters) - Solar companies Suntech Power Holdings Co Ltd <STP.N> and Trina Solar Ltd <TSL.N> said their first-quarter margins were squeezed as they set aside money to offset anti-dumping tariffs imposed by the U.S. government on solar panel imports from China.

(Reuters) - Solar stocks slumped to fresh lows on Friday as investors continued to punish Chinese solar companies a day after the United States said it would impose new duties on imports from the world's leading solar manufacturer.

Shares of Chinese solar-panel makers fell Thursday after the U.S. Commerce Department moved to impose high tariffs on their products.

(Reuters) - Shares of silicon wafer maker MEMC Electronic Materials Inc <WFR.N> fell 10 percent to their lowest in more than five years after the company posted a bigger-than-expected quarterly loss weak demand for its solar products.

Though it posted a surprise quarterly loss on Thursday, First Solar has raised its profit outlook.

Stocks ended near session highs Tuesday, with all three major averages logging their best rally in a month, helped by a handful of positive earnings reports and as fears over Europe diminished.

A glut in solar panels has driven down prices, and the oversupply may take a while to clear, according to industry executives. At the same time, low-cost natural gas is making gas-fired plants more attractive. the New York Times reports.

Suntech Power Holdings’ chief executive said the Chinese solar company expects to return to profit, along with the entire industry, as prices stabilize.

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Investors in the solar industry have needed a strong stomach this year, and that’s unlikely to change soon.