5 Best Renewable Energy Penny Stocks to Buy

4. Clean Energy Fuels Corp. (NASDAQ:CLNE)

Number of Hedge Fund Holders: 21

Clean Energy Fuels Corp. (NASDAQ:CLNE) is one of the best renewable energy penny stocks to buy.

On March 4, 2026, Clean Energy Fuels Corp. said it signed and extended a series of renewable natural gas-related agreements across trucking, refuse, transit, municipal, and airport fleets in the U.S. The company said the deals cover both RNG supply and fueling infrastructure services, reflecting continued adoption of the fuel across multiple end markets.

Among the announced agreements, Ecology Transportation Services will fuel its 150-vehicle RNG trucking fleet through Clean Energy under a deal expected to cover about 2.1 million gallons annually across California, Arizona, and Nevada. WMATA also extended its relationship with the company under a new operations and maintenance contract tied to five million gallons of fuel for more than 400 buses.

The release also said Clean Energy will provide RNG to 78 Arlington Transit buses, totaling roughly 750,000 gallons annually, while Phoenix-area transit infrastructure maintained by the company supports 335 natural gas buses and dispenses about 4.7 million gallons per year. Other agreements mentioned Recology, Scottsdale, Nashville International Airport, and Fort Smith. Senior Vice President Chad Lindholm said fleets are choosing RNG because it is clean, affordable, domestically produced, and supported by an established fueling network.

Clean Energy Fuels Corp. (NASDAQ:CLNE) is a U.S. provider of renewable natural gas and fueling solutions for transportation fleets. The company operates fueling stations across the U.S. and Canada and also develops RNG production facilities at dairy farms.