By last fall, Trina Solar (NYSE: TSL) had established itself as a premier player in the solar space. The company's costs were cratering, and margins were far fatter than those of Trina's fellow crystalline silicon module makers.

As of the second quarter, Trina's gross margins weighed in at a meaty 32.1%. Let's have a look at where those stand relative to some peers:

Company

Gross Margin %

SunPower (Nasdaq: SPWRA)

22.9%

Yingli Green Energy (NYSE: YGE)

33.5%

JinkoSolar (NYSE: JKS)

26.9%

Suntech Power (NYSE: STP)

18.2%

Trina still shines in this category, but no longer steals the spotlight, now that Yingli has closed the gap. Newcomer JinkoSolar isn't terribly far behind, either. Former darlings SunPower and Suntech have been left in the dust -- at least according to this metric. Gross margins don't tell the whole story when it comes to profitability, but they are a useful shorthand.

It's important to note that Trina isn't skimping on quality as it cranks out its low-cost solar wares. Discerning buyers like Southern California Edison, MEMC Electronic Materials (NYSE: WFR) subsidiary SunEdison, and Enfinity have all turned to Trina for top-performing modules.The company definitely has the "bankability" factor that we talked about in our recent look at SunPower's quarterly results.

Solar is a commoditized business, but this matter of whether a panel passes muster with project financiers does provide a bit of a buffer for the companies that are delivering the high-quality goods. Barring another collapse in the alternative energy project finance space, Trina should have no problem selling out its capacity, even in periods of industry oversupply.

Of course, that exact reasoning may lead Trina, Yingli, and other leaders to get overly comfortable with their expansion plans, and ultimately overshoot global demand. Trina is expanding cell and module capacity from 950 megawatts to 1,500 megawatts by the end of next year, in which it seeks to secure 10% to 11% global market share.

The company is clearly looking for a strong 2011, but visibility tends to be pretty limited in this business. I don't envy Trina's task of making these planning decisions. Whether or not we see continued strength in the solar sector next year, the company is definitely one of the best positioned to profit over the long haul. This stock would be near the top of my list if I were looking for solar exposure today.