The Cambridge Energy Storage Project in Cambridge, Minnesota will deploy Form Energy’s iron-air battery technology, capable of storing energy for up to 100 hours, or several days, the company said.

Form Energy said this is the first commercial deployment of the company’s iron-air battery. The system will be manufactured at the company’s Form Factory 1 in Weirton, West Virginia, and is expected to be operational by late 2025.

Following the project’s completion, Great River Energy plans to conduct a multi-year study to evaluate the system’s performance and potential for broader deployment. 

Iron-air battery technology uses the principle of reversible rusting. The battery cells contain iron and air electrodes and are filled with a water-based, nonflammable electrolyte solution. While discharging, the battery absorbs oxygen from the air and converts iron metal to rust.

While charging, the application of an electrical current converts the rust back to iron and the battery emits oxygen. The technology has lower costs compared to lithium-ion battery production.

Form Energy has several iron-air battery projects underway across the U.S.

One plan is to deploy 10 MW/1,000 MWh systems at two retiring Xcel Energy coal plants: The Sherburne County Generating Station in Becker, Minnesota and the Comanche Generating Station in Pueblo, Colorado.

Form Energy also has an agreement with Georgia Power to deploy a 15 MW/1500 MWh iron-air battery system in Georgia. The multi-day battery system could come online as early as 2026. 

Company co-founder and CEO Mateo Jaramillo appeared on the Factor This! podcast last year, where he discussed the company’s history and its recent efforts to commercialize its 100-hour battery.

Episode 54 of the Factor This! podcast features Form Energy co-founder and CEO Mateo Jaramillo, a former Tesla executive pushing for deep decarbonization on the grid. Subscribe wherever you get your podcasts.

The projects will be located where the utility plans to retire two coal-fired plants in Minnesota and Colorado. Each will utilize Form Energy’s iron-air battery technology and have the capacity of 10 MW/1,000 MWh.

The Minnesota Public Utilities Commission has already approved the iron-air battery project at the Sherburne County Generating Station site in Becker, Minnesota. Construction is expected to begin in the second quarter of 2024. The project is to be located near one of the largest solar developments in the U.S., the upcoming 710 MW Sherco Solar project.

Pending approval from the Colorado Public Utilities Commission, work on the Colorado battery system could begin in late-2024. The battery would be located at the Comanche Generating Station site in Pueblo, Colorado. The request is part of a $15 billion utility proposal to add wind, solar, natural gas, biomass and energy storage resources to meet the state’s forecasted demand through 2028.

Xcel said the Colorado plan, which calls for 6,500 MW of new renewable energy and battery storage resources, would double the amount of renewable energy on its system in the state.

The $70 million award comes from a total of $325 million announced by DOE for 15 long-duration energy storage projects across 17 states and one tribal nation. The funding comes from the Infrastructure Investment and Jobs Act (IIJA).

Separate from the DOE funding, Xcel Energy received a $20 million grant commitment in April 2023 from the Breakthrough Energy Catalyst fund for the Minnesota and Colorado battery systems. In addition to the grants, Xcel Energy plans to use standalone storage tax credits in the federal Inflation Reduction Act to further lower the cost of the projects.

Form Energy has signed deals to deploy its battery with utilities such as Xcel Energy, Southern Company, and Great River Energy, and recently broke ground on a commercial-scale battery plant in West Virginia.

At a high level, the basic principle of Form Energy’s battery operation is reversible rusting. The battery contains an iron anode, resembling an automobile’s brake pad, and an air-breathing cathode. They are submersed in an electrolyte water bath with a permeable separation between them.

When the iron is exposed to the oxygen and air, it triggers a chemical process called oxidation – otherwise known as rusting. That oxidation process releases electrons that are separated and sent to the grid – providing electricity when demand exceeds supply.  When there is excess power on the grid, the process is reversed and electrons flow in, releasing the oxygen and causing the iron to unrust, taking it back to a metallic state.

Form Energy received the largest award of $12 million. The company plans to develop, design and construct a 10 MW/1,000 MWh iron-air battery system with a project location still to be determined. Form Energy has signed deals to deploy its battery with utilities such as Xcel Energy, Southern Company, and Great River Energy, and recently broke ground on a commercial-scale battery plant in West Virginia.

Ecolectro, Inc. received $1.08 million to scale-up the company’s polymer chemistry and materials it expects to significantly reduce the cost of producing hydrogen by electrolysis and create a drop-in replacement for current designs. This project entails scaling laboratory-proven technologies with engineering and validation prototypes to build and test 10 kW electrolysis units. The electrolyzer will be deployed in a pilot demonstration in partnership with Liberty Utilities in Massena, New York.

PolyJoule, Inc. received $1.03 million. The company plans to install a 2 MWh, 167 kW PolyJoule modular battery storage system in partnership with Eastern Generation at its Astoria Generating Station located in Queens, New York. This demonstration aims to prove the safety, technical, operational and economic merits of the PolyJoule Conductive Polymer BESS in a densely populated urban setting.

Urban Electric Power (UEP) received $703,965 to install a 100 kW/1 MWh battery storage system, anchored by the company’s rechargeable zinc alkaline battery technology. The proposed project will be designed for 10- to 24-hour applications at commercial and industrial facilities. The project is located in Pearl River, New York.

In addition to these awards, the state also opened up $8.15 million in funding to support innovative long duration energy storage solutions, devices, software, controls, and other complimentary technologies yet to be commercialized.

Officials say project submissions should advance, develop or field-test hydrogen, electric, chemical, mechanical or thermal-electric storage technologies that will address renewable integration challenges, such as grid congestion, hosting capacity constraints and siting in New York City.

New York State has a goal to install 3,000 MW of energy storage by 2030.

Georgia Power first teased the collaboration in its 2022 Integrated Resource Plan as part of an effort to shift to a cleaner resource mix and eventually introduce long-duration or multi-day storage applications.

In its IRP the utility said it planned to evaluate opportunities in the 5-15 MW range to deploy this
technology and it would return to Georgia regulators for project approval once it identified an optimal application.

Form Energy is backed by the Bill Gates-led investment fund Breakthrough Energy Ventures. The company says its first announced commercial product, the iron-air-exchange battery, can deliver 100 hours of electricity at a price of less than $20/kWh.

Form says the technology’s basic principle of operation is reversible rusting. While discharging, the battery breathes in oxygen from the air and converts iron metal to rust. While charging, the application of an electrical current converts the rust back to iron and the battery breathes out oxygen.

The companies will continue to fully evaluate that the 100-hour iron-air battery technology will strengthen Georgia’s electric grid against normal day-to-day, week-to-week, and season-to-season weather variability. This analysis includes modeling by Georgia Power and Form Energy’s operational modeling tool for power grids.