As 2011 comes to a close, it's a great time to look back at what happened to the stocks that interest you. By making sure you know the important things that a company accomplished -- as well as the setbacks it experienced -- you can make a better decision about whether it's a smart investment for your portfolio.

Today, let's take a look at Capstone Turbine (Nasdaq: CPST). The company has been at the forefront of the microturbine business for years, as it tries to offer another energy alternative to grid-based electricity production. But historically, Capstone has struggled to become profitable. Below, I'll take a closer look at the events that moved Capstone Turbine's shares this year.

Stats on Capstone Turbine

Year-to-Date Stock Return 12.2%
Market Cap $281 million
Total Revenue, Trailing 12 Months $98.7 million
Net Loss, Trailing 12 Months ($38.6 million)
1-Year Revenue Growth 46.7%
Cash / Debt $20.3 million / $12.4 million
CAPS Rating (out of 5) ***

Sources: S&P Capital IQ, Motley Fool CAPS.

How did Capstone Turbine do this year?
Capstone Turbine makes microturbines that generate electricity independently of the power grid. With an increasing focus on alternative energy lately, Capstone seems well positioned to take advantage of investor interest in the area.

Off-grid power has come quite in handy for certain applications, especially oil and gas drilling sites where power isn't always readily available. For instance, Capstone identified the Eagle Ford shale play as a potential source of growth for the company. With players ranging from giants Chesapeake Energy (NYSE: CHK) and EOG Resources (NYSE: EOG) to smaller companies such as Magnum Hunter Resources (NYSE: MHR) and SM Energy (NYSE: SM), the Eagle Ford has plenty of potential to drive supporting companies like Capstone higher.

This year actually marked a milestone for Capstone: It made money in its most recent quarter. Granted, $1.3 million in a quarter isn't huge, but it could represent a true turning point in what has been a long series of struggles for the company to become profitable. Yet with General Electric (NYSE: GE), Caterpillar (NYSE: CAT), and other large competitors poised to take advantage of any opportunities they can, Capstone will still have to work hard to make the most of its position.

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Click here to add Capstone Turbine to My Watchlist, which can find all of our Foolish analysis on it and all your other stocks.