Looking back, the rebound in the global economy through the course of 2009 was impressive, and perhaps nowhere more pronounced than in the solar space. One of the striking things about Canadian Solar's (Nasdaq: CSIQ) year-end report was the huge increase in sales from the first quarter ($49 million) to the fourth ($288 million).

Canadian Solar is hardly alone in this respect. JA Solar (Nasdaq: JASO) launched from $34 million to $238 million in revenue, representing a sevenfold increase. Trina Solar (NYSE: TSL) lifted to $313 million from $132 million, which looks downright subdued in comparison.

You've always needed a strong stomach to invest in this market, and 2010 will prove no different. Heck, it already has -- the Claymore/MAC Global Solar Index (NYSE: TAN) exchange-traded fund has tumbled around 20% year to date.

With Germany reining in demand with a subsidy reduction that's likely to begin midyear, the big question is whether other markets like the U.S, Italy, and the Czech Republic can step in and pick up the slack. A sharp increase in Czech demand would be great for Canadian Solar, which claims to be the market leader there. Reports that the local grid is being overwhelmed by new solar and wind projects, that new projects are no longer being authorized by the state-run power company, and that feed-in tariff reductions are being considered may put a damper on growth beyond 2010, though.

On its conference call, Canadian Solar did its best to calm investor fears regarding the second half of the year. The company characterized the pipeline as "very strong," but left its full-year shipment guidance of 600 to 700 megawatts unchanged.

Even the bullish analysts out there seem to expect solar module price declines pushing 20% this year. It won't be the easiest year for solar companies, but low-cost players like Canadian Solar and Yingli Green Energy (NYSE: YGE) ought to fare relatively well. As long as Canadian Solar corrects its recent manufacturing issues in a prompt fashion, 2010 should be a reasonably good year. I wouldn't put money on it, though. I don't have the stomach for this sector.

Fool contributor Toby Shute doesn't have a position in any company mentioned. Check out his Motley Fool CAPS profile or follow his articles using Twitter. The Fool has a disclosure policy.