5 Best Renewable Energy Penny Stocks to Buy

1. Plug Power Inc. (NASDAQ:PLUG)

Number of Hedge Funds: 29

Plug Power Inc. (NASDAQ:PLUG) is one of the best renewable energy penny stocks to buy.

On March 9, 2026, Jefferies cut its price target on Plug Power Inc. (NASDAQ:PLUG) to $1.80 from $2.00 while maintaining a Hold rating, pointing to concerns about whether the company’s improving margin profile can be sustained. The note said Plug reiterated its expectation for positive EBITDA in 2026, but Jefferies still views that outlook as a “show me” story. The firm also said Plug’s fourth-quarter gross margin benefited partly from one-off items, even as it acknowledged better liquidity and expected performance support from material handling and electrolyzers in 2026.

For context, Plug reported fourth-quarter 2025 revenue of $225.2 million, up 17.6% from the prior-year quarter, while full-year 2025 revenue rose 12.9% to about $710 million. The company posted a positive fourth-quarter gross profit of $5.5 million, or 2.4% of sales, versus a gross margin loss of negative 122.5% a year earlier. Management said the improvement was driven by higher sales volume, a better mix, price increases on some offerings, fuel network enhancements, lower service cost per unit, and manufacturing efficiency gains tied to Project Quantum Leap.

Plug also ended 2025 with $368.5 million in unrestricted cash, said an asset monetization agreement is expected to generate more than $275 million, and reported that net cash used in operations fell 26.5% year over year to $535.8 million.

Plug Power Inc. (NASDAQ:PLUG) develops hydrogen fuel cell systems, electrolyzers, hydrogen production infrastructure, and related solutions for material handling, industrial, and energy markets.

While we acknowledge the potential of PLUG to grow, our conviction lies in the belief that some AI stocks hold greater promise for delivering higher returns and have limited downside risk. If you are looking for an AI stock that is more promising than PLUG and that has 100x upside potential, check out our report about this cheapest AI stock.

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