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 Westport Innovations (Nasdaq: WPRT). The company is in the forefront of alternative energy because of its natural-gas burning engines, which produce reduced emissions and herald the possible future of increased use of natural gas over diesel and gasoline engines. That has a lot of investors interested in the future of this innovative company.

Stats on Westport

Year-to-Date Stock Return 55.1%
Market Cap $1.42 billion
Revenue, Trailing 12 Months $207.7 million
1-Year Revenue Growth 44%
1-Year Profit Growth NM (loss of $60.5 million over past 12 months)
CAPS Rating (out of 5) *****

Source: S&P Capital IQ. NM = not meaningful.

What happened to Westport this year?
Westport is a small company, but it's made a lot of progress this year. The company has had a long-standing partnership with engine giant Cummins (NYSE: CMI), and that relationship has borne fruit recently, with revenues for the joint venture rising almost 60% in the most recent quarter.

But Westport has seen some exciting new initiatives take root this year. Caterpillar (NYSE: CAT) made an agreement with Westport to incorporate Westport technology into large heavy-duty engines. Meanwhile, General Motors (NYSE: GM) wants Westport to help design engines for lighter-duty vehicles, while Ford (NYSE: F) is working with Westport on a gasoline/natural-gas bi-fuel truck.

Also, the company joined up with Royal Dutch Shell (NYSE: RDS-A) to form a co-marketing program. Combined with natural-gas fueling stations at Shell's Flying J truck stops, Westport and Shell could create an integrated natural-gas solution for truckers that could potentially rival the efforts of Clean Energy Fuels (Nasdaq: CLNE).

The biggest problem for Westport is that its losses have continued to widen. But shareholders are still optimistic, and with the huge interest in natural gas -- especially in the U.S. -- Westport appears to have a strong position to capitalize on whatever the future brings. With oil prices still near triple digits, natural gas looks like a smart alternative.

Westport isn't the only stock that could benefit from high oil prices, though. Learn more about three other stocks that will prosper from $100 oil in the Motley Fool's latest special free report on energy. It's yours free, but only for a limited time, so take a look today.

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