Have you heard this one before? A solar power company posts some dreary news after a slumping demand in the first-quarter for its product. Well, now you've heard it again, this time regarding Yingli Green Energy ( YGE). The company, a China-based photovoltaic product manufacturer, missed Street estimates by a wide margin. This morning, it reported a loss of $20.7 million, or 16 cents per ADS, compared with income of $31.9 million, or 25 cents, in the year-ago period. After excluding certain items, the net loss came to $11.3 million, or 9 cents per ADS. Because of declining PV prices, revenue fell to $146.3 million. Analysts' consensus centered on the company losing only a penny per share on $194.4 million in revenues. The stock was changing hands in red territory today, with the share price at $9.72, down 39 cents, or nearly 4%, during midday trading. "Due to weakened macroeconomic conditions globally, including tighter credit for PV system project financing, worse than normal winter weather conditions in Germany and changes in the feed-in tariff policy in Spain, we experienced a tough quarter," Chairman and CEO Liansheng Miao said in a release. He went on to say, "we believe that the first quarter marked a low point for the entire solar industry this year, Yingli Green Energy included." For the full year, the company said it expects gross margins to land between 23% and 25% when taking into account currency exchange rates and a downturn in prices for PV modules. Suntech Power ( STP), another PV maker, and ReneSola ( SOL - Get Report), manufacturer of wafers for solar panels, both announced revenue slides during their earnings posts yesterday.