Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Tuesday was a terrible day for solar power companies in general, and Chinese ones in particular. Yingli Green Energy Holding (NYSE: YGE) was swept up in the downtrend, with a 10.2% intraday fall from last night's close.

So what: Chinese interest rates got hiked 0.25% today, kicking off rumors that Beijing might let the yuan strengthen versus the U.S. dollar and other currencies. That move would force Chinese businesses like Yingli into a conundrum: raise prices to account for the relatively higher cost of making its solar panels, or live with lower profits instead.

Now what: The Chinese government has not officially stated any intention to raise the value of its currency, so I think you still have to treat this purported threat to Yingli's profitability as a rumor. There is ample reason to believe in a strong solar market in 2011. Yingli and fellow Chinese solar power experts LDK Solar (NYSE: LDK) and JA Solar Holdings (Nasdaq: JASO) -- both of which fell harder than Yingli today -- all look like potential buy-in situations today.

Interested in more info on Yingli Green Energy? Add it to your watchlist by clicking here.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Motley Fool is investors writing for investors.