Over the past decade, the demand for renewable energy has skyrocketed amid more aggressive decarbonization initiatives and the growth of the power-hungry cloud infrastructure and artificial intelligence (AI) markets. To capitalize on that secular trend, investors should take a closer look at renewable energy stocks with plenty of long-term growth potential.

Two of those stocks are CleanSpark (CLSK +1.33%) and Plug Power (PLUG +0.13%). Both stocks seem volatile today, but they might be worth holding for the next few decades.

CleanSpark

CleanSpark originally built microgrids to store wind, solar, and other renewable energy sources. Its clients could deploy those compact systems as stand-alone power sources or plug them into existing energy grids, load management systems, and backup generators.

In 2021, it acquired the Bitcoin (BTC 0.10%) miner ATL Data Centers and upgraded its miners with its own microgrids. It subsequently purchased additional Bitcoin mining companies, upgraded their operations in the same way, and mined more Bitcoins on its own. It then began selling those Bitcoins to fund the expansion of its AI infrastructure business, which provides AI-ready data centers powered by its green-energy microgrids rather than fossil fuels.

CleanSpark

Today’s Change

(1.33%) $0.21

Current Price

$15.97

That evolution turned CleanSpark into a unique company that addresses the notion that data centers for Bitcoin mining and AI processing are harmful to the environment. It also helps those companies reduce their energy costs and long-term exposure to volatile oil and gas prices.

For 2026, analysts expect its revenue to decline 16% as its adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) turn negative. That decline can be attributed to Bitcoin’s retreat from its record highs, adverse weather conditions that further reduced its mining revenue, and its transition into an AI infrastructure provider.

But in 2027, they expect its revenue to rise 17% as its adjusted EBITDA turns positive again. That recovery should be driven by the expansion of its AI infrastructure business, which aims to gain its first hyperscaler customers this year, and Bitcoin’s stabilization and potential recovery. With an enterprise value of $5.47 billion, it isn’t a bargain at nine times next year’s revenue, but its growth could accelerate significantly after it locks in its first hyperscale customers.

Plug Power

Plug Power is a leading developer of hydrogen fuel cells, electrolyzers, and storage systems. It generates most of its revenue by selling fuel cells and charging systems to Amazon and Walmart for their hydrogen-powered forklifts. Its electrolyzers are also essential for the production of “green” hydrogen — which uses a renewable energy source (like wind or solar) to split the water molecules.

Plug Power’s total number of deployed fuel cell systems rose from about 50,000 at the end of 2021 to more than 74,000 systems at the end of 2025. It expanded rapidly in 2022 and 2023, and its acquisitions of two smaller cryogenic storage companies amplified that growth.

Plug Power

Today’s Change

(0.13%) $0.01

Current Price

$3.79

In 2024, Plug’s growth stalled out after it lapped those acquisitions, and the macro headwinds drove many companies to pause their hydrogen projects. But in 2025, its growth accelerated as interest rates declined and its government clients restarted their green hydrogen projects. It also streamlined its operations and reined in spending through its “Project Quantum Leap” initiative.

From 2025 to 2028, analysts expect Plug’s revenue to grow at a 18% CAGR, with its adjusted EBITDA turning positive in the final year. With an enterprise value of $6.1 billion, it still looks reasonably valued at six times next year’s sales.

Plug’s stock still looks speculative today, but the green hydrogen market could still expand at a 30.2% CAGR from 2026 to 2033 across the industrial, transportation, and power generation sectors, according to Grand View Research. If Plug maintains its first-mover advantage in this nascent market, it could be revalued as a hypergrowth stock within the next few years.