Eos Energy Lifts Q3 Revenue 171% to $82.7 Million on Zinc Batteries

• Eos Energy's Q3 2026 revenue rose 171% year on year to $82.7 million, from deliveries to 10 projects.
• Gross margin improved 58 percentage points to minus 53%, so the zinc battery maker still sells below cost.
• Eos kept its 2026 revenue outlook at the lower half of $300-350 million as it moves Line 1 to Thorn Hill.

Eos Energy Enterprises, a US maker of zinc-based long-duration batteries, reported third-quarter revenue of $82.7 million on Nov. 5, up 171% from a year earlier and 20% from the second quarter, on deliveries to 10 projects.

Gross margin improved 58 percentage points to minus 53%, from minus 111% a year earlier, Eos said in a statement. It still sells batteries below cost. Adjusted EBITDA, a non-GAAP measure, was a loss of $63.8 million. Net income attributable to shareholders was $125.0 million, mainly from non-cash mark-to-market gains, its SEC filing shows.

The quarter in numbers

• 216% year-on-year growth in cube shipments, and 23% from the second quarter.
• 96 percentage points of year-on-year improvement in the adjusted EBITDA margin (non-GAAP), to minus 77%.
• $765 million of backlog, representing 3.2 GWh, down 5% from the second quarter.
• About $239 of backlog per kWh, and about $8.3 million of revenue per project delivered (list.solar calculation).
• $91.5 million to $116.5 million of fourth-quarter revenue is implied by the lower half of guidance (list.solar calculation).
• 3.5 hours was the average duration of US batteries installed in the second quarter, Wood Mackenzie and the American Clean Power Association said.

In September Eos agreed with MN8 Energy and Google to supply a 10-hour, 10-MW/100-MWh Z3 system to MN8's Mammoth Solar project in West Virginia. The project also includes 86 MW of solar and 70 MW/280 MWh of lithium-ion storage; the Eos unit is due online in 2030.

In September Eos received an $87 million first advance under the second tranche of its Department of Energy loan, taking total draws to about $178 million. Cash, including restricted cash, was $344.1 million on Sept. 30.

The company is consolidating battery production at Thorn Hill in Warrendale, Pennsylvania, which moved to 24-hour operations in October. Line 1 disassembly began in late October at Turtle Creek, the plant Eos took full control of in 2021. Eos said the move lowers fourth-quarter capacity and affects the timing of some shipments.

"We remain on track to achieve the lower half of our full-year revenue outlook," CEO Joe Mastrangelo said. The range is $300 million to $350 million, narrowed in August from $300 million to $400 million.

Eos expects Line 1 to resume production near the end of the first quarter of 2027. Thorn Hill would then have about 4 GWh of annual nameplate capacity on two lines.