Key Points
Eos Energy Enterprises is rapidly scaling its zinc-based battery production to meet utility-scale storage demand.
Plug Power maintains a dominant footprint in the green hydrogen ecosystem through massive fuel cell deployments.
Which of these clean energy players is the better addition to your portfolio in 2026?
The clean energy transition is accelerating, but choosing the right vehicle for your capital is difficult. Should you favor Eos Energy Enterprises (NASDAQ:EOSE) or the hydrogen giant Plug Power (NASDAQ:PLUG)?
Eos focuses on zinc-based batteries designed for long-duration storage, offering an alternative to traditional lithium-ion tech. Plug Power provides a comprehensive green hydrogen ecosystem, serving massive logistics fleets with fuel cells. Both companies occupy critical niches in the evolving energy landscape, making them frequent candidates for comparison among growth-oriented investors.
The case for Eos Energy Enterprises
Eos Energy Enterprises designs and manufactures zinc-based long-duration energy storage systems. These systems target utility-scale and industrial applications, providing a non-flammable alternative to lithium-ion batteries. In its latest annual report, filed for 2025, the company highlighted its focus on the U.S. market. Customer concentration like this adds a layer of risk to the business, as two specific clients accounted for nearly 52% and 19% of total revenue.
In FY 2025, revenue reached about $114.2 million, representing a significant increase of approximately 630% over the previous year. This rapid top-line growth shows the company is scaling its production capabilities to meet demand for industrial stocks. Despite this growth, Eos reported a net loss of nearly $970 million. This loss reflects the high costs of expanding manufacturing and the early-stage nature of its commercial rollout.
As of its December 2025 balance sheet, the debt-to-equity ratio is negative 1.0x, which means total liabilities exceed shareholder equity. The so-called current ratio stands at approximately 4.9x, measuring a company's ability to pay short-term debts with its current assets. During the same period, free cash flow was negative $265 million. Free cash flow is the cash a company generates after accounting for cash outflows to support operations and maintain its capital assets.
The case for Plug Power
Plug Power operates a comprehensive green hydrogen ecosystem, producing, storing, and delivering hydrogen to power fuel cell systems. The company has deployed more than 74,000 fuel cell systems to large industrial partners. Large-scale fleet operators in material handling and logistics represent a core part of its business strategy. For the year ended Dec. 31, 2025, Walmart Inc(NASDAQ:WMT) accounted for roughly 24% of consolidated revenue, which indicates substantial customer concentration risk.
In FY 2025, revenue reached nearly $710 million, an increase of approximately 13% compared to the prior year. While revenue continues to grow, the company reported a net loss of roughly $1.6 billion. The negative net margin of approximately 230% indicates that expenses far exceed the revenue generated from its hydrogen and fuel cell sales. Management continues to focus on cost-cutting initiatives and strategic realignments to narrow these losses.
As of its December 2025 balance sheet, the debt-to-equity ratio was nearly 1.0x, indicating that the company uses an equal amount of debt and equity to finance its assets. Its current ratio was approximately 2.3x, suggesting the company has more than twice the assets needed to cover its immediate liabilities. Free cash flow for the period was negative $661.5 million. This reflects the capital-intensive nature of building out green hydrogen production facilities across multiple states.
Risk profile comparison
Eos Energy Enterprises faces significant financial risks, including a history of net losses and a heavy reliance on outside capital. If the company fails to meet loan covenants under its Department of Energy loan facility, its operations could be severely impacted. The business must also scale manufacturing at its Turtle Creek facility while navigating securities fraud class action lawsuits. Finally, Eos competes against established lithium-ion providers like Tesla Inc (NASDAQ:TSLA) and Fluence Energy (NASDAQ:FLNC) in a crowded storage market.
Plug Power deals with its own liquidity challenges, having incurred consistent negative operating cash flows that necessitate frequent capital raises. The company faces uncertainty regarding federal loan programs and potential impairments of its long-lived assets. Supply chain volatility for critical materials like iridium and hydrogen remains a constant pressure on its operating margins. Additionally, the company is involved in class action lawsuits and faces competition from large industrial players such as Acciona (OTC:ACXIF).
Valuation comparison
Neither company has a forward price-to-earnings ratio because neither is expected to post a profit in its coming fiscal year. Plug Power trades at a more reasonable price-to-sales ratio, although Eos's level is not cause for concern.
| Metric | Eos Energy Enterprises | Plug Power |
|---|---|---|
| Forward P/E | n/a | n/a |
| P/S ratio | 6.9x | 3.8x |
Valuation metrics sourced from Financial Modeling Prep (FMP) and may differ from other data providers.
The Forward P/E ratio helps investors understand how much they are paying for each dollar of future earnings estimates. The P/S ratio compares the company's market value to its sales over the past twelve months.
Which stock would I buy in 2026?
Plug Power's fuel cells run on clean-burning hydrogen, though creating hydrogen is often done in a process fueled by natural gas. Still, Plug Power sits firmly in the renewable energy niche, benefiting from many countries' moves toward green (non-fossil-fuel-derived) hydrogen. It is also benefiting from the datacenter boom and from restored tax credits that make its systems more affordable to deploy.
For fiscal 2026, revenue growth is pretty good, with Wall Street analyst consensus predicting a nearly 15% increase to $812 million. The net loss is seen narrowing to about $580 million.
Similarly, the current fiscal year, 2026, looks to be a major step forward for Eos Energy Enterprises. The business has already sold more products through the first half of the year than it did in all of 2025, shipping $126 million of gear to clients.
The longer term should be much greater. Management says it has nearly $25 billion of business pipeline, meaning proposed energy storage developments Eos could bid on, and an $807 million backlog, which are firm orders for the company's products. 2026 revenue is expected to more than double.
Recently, Eos scored a high-profile deal to support the PJM grid after joining with Alphabet Inc (NASDAQ:GOOGL) and MN8 Energy on a solar energy storage project in West Virginia.
Both businesses offer investors a way to play the rise in demand for power storage brought about by AI data center demand and the need for storage for renewable energy production. Plug Power, with its lower P/S ratio and more established customer base, seems to be the better bet for long-term investors,
Brendan Coffey has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Alphabet, Fluence Energy, Tesla, and Walmart. The Motley Fool has a disclosure policy.