What happened

Shares of natural gas fuel specialist Clean Energy Fuels (CLNE 4.26%) rose 10.9% in August, according to data provided by S&P Global Market Intelligence, slightly outpacing the S&P 500's 7% gain. That marked the second straight month of outperformance for Clean Energy and firmly put it in positive territory for 2020. Clean Energy's stock is up about 10.7% year to date. 

So what

In early July, Clean Energy's shares got a big boost when oil major Chevron announced it was partnering with the company to promote renewable natural gas fuel in truck fleets serving the Port of Los Angeles. Clean Energy's renewable natural gas fuel, branded Redeem, has been one of its hottest products.

A semi truck fills up at a Clean Energy Fuels filling station.

Image source: Clean Energy Fuels.

Fast-forward a month: On Aug. 4, oil major BP (BP 0.82%) reported its second quarter 2020 earnings, and they were -- unsurprisingly -- dismal. In response, BP's management slashed its dividend, which ate up much of the company's earnings coverage. However, BP also outlined a strategic refocus for the company that involved cutting hydrocarbon investment by 40% by 2030 and investing $5 billion per year in renewable energy. 

When one of the world's biggest oil companies announces that even it's shifting away from oil, renewable fuel companies stand to benefit, and it looks like investors felt comfortable investing in Clean Energy Fuels.

Now what

Renewable energy fuel stocks are finally starting to get noticed by investors, but there are now so many technologies in play -- including renewable natural gas, biodiesel, hydrogen fuel cells, and, of course, batteries -- that it's tough to know if they'll all be able to coexist or if one technology will win out while the others fizzle.

The beaten-down Clean Energy is still a risky stock, but it has a lot of upside potential. Investors who can stand the risk can view this as a good time to hop on board.