Market turmoil makes it easy, perhaps too easy, to justify selling a stock these days. And while making off-the-cuff decisions isn't going to help your portfolio, it's still a good idea to play devil's advocate with investments.

Consider solar module supplier Canadian Solar (NASDAQ:CSIQ). Though there's strong momentum behind the global push for alternative energy, you'll find plenty of the 1,114 Motley Fool CAPS members who have weighed in on the company offering reasons to be bearish.

At The Motley Fool, we like to consider both the good and bad sides of an investment. Here, I've highlighted three of the main bearish arguments on two-star Canadian Solar. Be sure to read the bullish side as well, and then weigh in with your own comments below or rate Canadian Solar in CAPS.             

1. Supply issues looking ugly
A recent iSuppli report highlighted the current glut in solar supply, and solar sector analyst Gordon Johnson with Hapoalim Securities recently said solar faces a big supply/demand imbalance through next year. He expects next year's industry supply to be about 10.8 gigawatts, with demand coming in at just 6 gigawatts, a disparity that could have a major effect on Canadian Solar and others like SunPower (NASDAQ:SPWRA). He also said that investors' hopes that China will be a big driver of demand are "overblown."

2. Bearish sentiment
Similar to others such as China Sunergy (NASDAQ:CSUN), First Solar (NASDAQ:FSLR), and Trina Solar (NYSE:TSL), Canadian Solar sports a lowly two-star rating in CAPS, as members anticipate it will underperform the market. Add in a stock price that has almost tripled this year and some recent downgrades throughout the sector, and Canadian Solar may not be a good bet.        

3. Waning support
High levels of financing and government subsidies are two very important drivers of sales of solar products; both are increasingly difficult to come by. The recession tightened up credit and some investors anticipate further incentive cuts in European countries. And China's delayed introduction of a feed-in tariff may throw a very wet blanket on projects for companies like Canadian Solar as well as peers Yingli Green Energy (NYSE:YGE) and Suntech Power (NYSE:STP).

To see details of what CAPS members are saying now about Canadian Solar, just click on over to Motley Fool CAPS and have a look. Or add your own thoughts directly to this story in the comments box below.

And don't forget to click over and get the sunny side of the argument on Canadian Solar.

Always looking ahead, the Motley Fool Rule Breakers service has already recommended several alternative energy stocks poised to prosper. To see what other rule-breaking stocks David Gardner is picking today, take a free 30-day trial.

Fool contributor Dave Mock takes each day as it comes and owns no shares of companies mentioned here. First Solar and Suntech Power Holdings are Rule Breakers selections. The Fool's disclosure policy is preparing for a long vacation that will bring it back refreshed and ready to take on the world once again.