Backgrounder Google will buy the output of the Eos zinc batteries, one of the largest deployments of that chemistry built to date. Both hope it will prove zinc is now practical. Eos has taken numerous orders for zinc, which is designed to last longer than lithium. I’m reaching out to the company about what they can deliver, when, and the cost.
Part of The Battery Project, my attempt to learn and report what’s possible. Here’s Claude’s backgrounder and the announcement pr. Lightly edited; confirm any data before using.
The Deal
MN8’s Mammoth Solar project — no relation to Doral Renewables’ 1.3-GW project of the same name in Indiana — sits on a former coal mine in Kanawha County, West Virginia, and interconnects into PJM. Google is buying the energy, capacity, and clean attributes; MN8 is the developer and will own and operate the finished project, with Google coming in as offtake partner after the project was already in development. The stack, per Utility Dive: 86 MW of solar, 70 MW/280 MWh of lithium-ion storage, and 10 MW/100 MWh of Eos zinc-based long-duration storage. Solar reaches commercial operation in 2028, with storage following in 2029 and 2030 — the companies haven’t publicly specified which technology lands in which year.
The stated goal is shaping solar output to match Google’s regional data center load curve, not just adding clean megawatts to the grid. That lands at a specific moment: PJM capacity prices have hit the auction ceiling in recent cycles, and a one-time backstop auction this fall is meant to cover a roughly 7 GW shortfall. (That’s a PJM figure and probably much too high, I’m reporting. Dave)
MN8 CEO Jon Yoder credited Google for being “willing to pair next-generation storage with utility-scale solar.”
The Zinc Bet
The number that matters isn’t the solar capacity — it’s the 100 MWh of zinc storage. Per DOE, most operational zinc battery deployments run at 1 MW or less. Eos’s chemistry swaps lithium’s electrolyte for a nonflammable zinc-based one and can discharge economically past the eight-hour mark.
MN8 and Eos aren’t starting from scratch here: the two signed a supply agreement in October 2025 covering up to 750 MWh of Z3 battery modules across PJM and other U.S. markets, with the first tranche of projects pairing 200 MWh of 10-hour storage with solar. A company spokesperson has said Mammoth Solar’s zinc allocation is drawn directly from that master supply agreement — a link the companies’ own joint announcement didn’t spell out. Google is running a parallel long-duration bet with Xcel in Minnesota, a 300 MW/30 GWh Form Energy iron-air system that can discharge for up to 100 hours, suggesting the zinc buy here is one piece of a broader push to diversify past lithium-ion for turning intermittent solar into steady, dispatchable load. (Iron air appears to lose about half the initial energy load before it delivers. Dave)
edited and authored by Dave with close collaboration by Claude
Here’s the pr
MN8, Google, and Eos 10 MW of Zinc Bateries to West Virginia
Sep 2, 2026 | 4 min read
The collaboration pairs utility-scale solar with lithium-ion energy storage and American-made, zinc-based long-duration energy storage to deliver new clean energy and capacity to the PJM grid
This announcement originally appeared on BusinessWire.
NEW YORK, NY, PITTSBURGH, PA — September 2, 2026 — MN8 Energy (MN8), a scaled power platform, Eos Energy Enterprises (NASDAQ: EOSE) (Eos), a U.S. manufacturer of zinc-based long-duration energy storage systems, and Google, today announced a collaboration to deliver new, clean, around-the-clock energy resources to the PJM grid in support of growing demand in the region.
Owned and operated by MN8, the project combines 86 MW of utility-scale solar, 10 MW/100 MWh of Eos’ Z3™ zinc-based long-duration energy storage, and 70 MW/280 MWh of lithium-ion energy storage. The integrated portfolio adds new clean, dispatchable capacity to the grid serving Google’s data centers in the region, including a planned project in West Virginia. The solar project is expected to reach commercial operation in 2028, with lithium-ion storage and long-duration storage following in 2029 and 2030, respectively.
An Innovative Capacity Solution
MN8 custom-designed its Mammoth Solar project in Kanawha County, West Virginia as an integrated utility-scale solar system with short- and long-duration storage that converts intermittent renewable generation into a single, dispatchable resource. The multi-technology solution fills a critical grid need by delivering clean capacity matched to data center load profiles. It’s the first commercial-scale long-duration energy storage deployment in West Virginia.
“At Google, we’re committed to backing solutions that both serve our data center capacity needs and accelerate progress toward cleaner, more affordable energy systems,” said Lucia Tian, Director, Advanced Energy Technologies at Google. “This collaboration with MN8 and Eos aims to deploy a smart portfolio of round-the-clock technology solutions to help power our digital infrastructure, while creating meaningful economic benefits for West Virginia.”
Under the agreement, Google will purchase the energy, capacity, and clean energy attributes of the project, advancing the company’s commitment to bring new capacity to the grids where it operates. The project is part of Google’s broader efforts to accelerate LDES technology commercialization with the aim to rapidly bring its potential to communities everywhere — making reliable, affordable electricity available around the clock and supporting the resilience of grids as they integrate growing amounts of renewable energy sources.
“This project reflects what MN8 does best: understanding a customer’s unique energy profile and building a solution around it,” said Jon Yoder, President and CEO of MN8 Energy. “Because Google was willing to pair next-generation storage with utility-scale solar, we could engineer proven and emerging technologies into one dispatchable resource – and deliver clean, around-the-clock power where the grid needs it most.”
Deploying American-made Long-Duration Energy Storage
The project marks Google’s first project that uses Eos’ American-made Z3 technology and the first project under the previously announced MN8-Eos Master Supply Agreement. The 10 MW/100 MWh system is designed to provide 10 hours of storage, extending the availability of solar generation beyond the shorter-duration energy storage resources and enabling the combined portfolio to deliver dependable capacity across more hours of the day. This project will prove how Eos’ aqueous zinc chemistry can support critical grid infrastructure.
“The grid needs more from every megawatt of new generation,” said Nathan Kroeker, Chief Commercial Officer at Eos. “Our work with Google is focused on deploying American-made long-duration storage where it solves real grid reliability challenges. Z3 extends the value of clean generation across more hours, strengthens the overall portfolio, and delivers more dependable capacity when it’s needed most.”
Creating Economic Benefits in West Virginia and Across the Region
Built on a reclaimed coal mine in West Virginia, this project is expected to create economic opportunity in a community with a long energy history. Based on MN8’s estimates, it represents up to $350 million in capital investment and is expected to generate approximately $4 million in property tax revenue for the county and local schools over the first 20 years of operations, with millions more in the 15-20 years that follow. Construction is expected to create approximately 200 jobs, with additional full- and part-time roles supporting the project throughout its operating life.
The project’s impact also extends across the PJM interconnection, connecting new energy infrastructure in West Virginia with American manufacturing and regional innovation. MN8 and Eos maintain significant operations and workforces across the Mid-Atlantic and Northeast, from MN8 projects spanning the region to Eos headquarters and manufacturing in Pittsburgh, Pennsylvania. Together, the companies support domestic supply chains and regional economies.
About MN8
MN8 is a scaled power platform that develops, owns and operates energy assets for the enterprises driving the new American economy. We help customers secure scaled power to support growth, resiliency and long-term energy goals. With more than 4 gigawatts of operating and under-construction assets across 29 states, MN8 is one of the largest independent power producers in the United States, serving more than 200 customers — including leading AI and hyperscale technology companies, Fortune 500 corporations and government agencies. Our integrated platform spans utility-scale solar, battery storage, EV and electrification infrastructure, and powered land capabilities. Founded within Goldman Sachs and operating independently since 2022, MN8 pairs institutional-grade financial discipline with full-lifecycle execution capabilities. MN8 is headquartered in New York, with offices in South Florida, Dallas and Madrid, Spain. Learn more at mn8.com.
About Eos Energy Enterprises
Eos is accelerating the shift to American energy independence with positively ingenious solutions that transform how the world stores power. The Company’s BESS features the innovative Znyth™ technology, a proven chemistry with readily available non-precious earth components, that is the pre-eminent safe, non-flammable, secure, stable, and scalable alternative to conventional technology. The Company’s BESS is ideal for utility-scale, microgrid, commercial, and industrial long-duration energy storage applications (i.e., 4 to 16+ hours) and provides customers with significant operational flexibility to cost effectively address current and future increased grid demand and complexity. For more information about Eos (NASDAQ: EOSE), visit eose.com.