Wind and solar power require inexpensive, long-lasting storage to mitigate their natural intermittency caused by weather patterns. Deborah Halber, in an article for MIT News, discusses the advancement of iron-air batteries.
Iron is abundant and affordable on a global scale. These batteries have a multi-day storage capacity, but they are heavier and require more space compared to lithium-ion batteries, which is not a concern for stationary grid storage.
The target cost of $20/kWh (one-tenth of the cost of lithium-ion battery storage) could enable wind and solar power to competitively deliver consistent and reliable energy, challenging traditional fossil fuel generation.
Form Energy, the company behind this innovation, received an order from Georgia Power in the U.S. for a 15-megawatt/1,500-megawatt-hour system last year and is constructing a new large-scale battery manufacturing facility in West Virginia. Such solutions are crucial for the transition to clean energy.
Halber also references studies projecting a global need for up to 140 terawatt-hours of grid storage by 2040.
Power generation during periods of limited sunlight. Form Energy utilizes MIT research to integrate renewable energy sources into the grid with iron and air-based batteries. By Deborah Halber, MIT News.
In 2016, at the CERAWeek energy conference in Houston, MIT materials scientist Yet-Ming Chiang and a Tesla executive discussed the challenge of storing solar and wind energy output for extended periods.
Chiang, the Kyocera Professor of Materials Science and Engineering, and Mateo Jaramillo, a vice president at Tesla, recognized the need for a cost-effective storage solution for renewable energy to meet peak demand and fill gaps during days with low wind or sunlight.
They also acknowledged the necessity of addressing the limited availability of raw materials used in traditional energy storage devices if renewable energy is to replace fossil fuels on a large scale.
By 2040, the global demand for energy storage is projected to reach up to 140 TWh.
Energy storage solutions have the potential to improve the accessibility of renewable energy, enhance the stability and dependability of power networks, and ultimately expedite the transition to decarbonized grids.
The global market for these systems — essentially large batteries — is expected to grow tremendously in the coming years.
A study by the nonprofit LDES (Long Duration Energy Storage) Council pegs the long-duration energy storage market at between 80 and 140 terawatt-hours by 2040.
“That’s a really big number,” Chiang notes. “Every 10 people on the planet will need access to the equivalent of one EV [electric vehicle] battery to support their energy needs.”
In 2017, Chiang and Jaramillo, who had met in Houston a year earlier, came together to establish Form Energy in Somerville, Massachusetts.
They were joined by MIT graduates Marco Ferrara SM ’06, PhD ’08 and William Woodford PhD ’13, as well as energy storage expert Ted Wiley.
“There is a burgeoning market for electrical energy storage because we want to achieve decarbonisation as fast and as cost-effectively as possible,” says Ferrara, Form’s senior vice president in charge of software and analytics.
Investors were in agreement. Form Energy would go on to secure over $800 million in venture capital over the next six years. The company’s focus was on developing iron-air batteries that are cost-effective and have a long duration.
A basic battery is made up of an anode, a cathode, and an electrolyte. When the battery discharges, electrons move from the negative anode to the positive cathode with the assistance of the electrolyte.
When the battery charges, an external voltage reverses this process, causing the anode to become the positive terminal, the cathode to become the negative terminal, and the electrons to return to their original positions.
Materials used for the anode, cathode, and electrolyte determine the battery’s weight, power, and cost “entitlement,” which is the total cost at the component level.
In the 1980s and 1990s, the introduction of lithium brought about a significant change in batteries, making them smaller, lighter, and with longer-lasting charge.
The storage systems developed by Form Energy are rechargeable batteries based on iron, which offers various advantages over lithium, particularly in terms of cost.
Chiang, who previously expressed his fondness for lithium-ion batteries, founded two out of four MIT spinoffs focused on innovative lithium-ion technology.
However, the high cost and limited storage capacity of lithium-ion batteries made them unsuitable for Chiang’s current vision.
Chiang aimed to develop a cost-effective approach that would enhance the appeal of renewable energy.
The goal was to make solar and wind energy dependable for a large number of consumers by storing it for longer periods to bridge gaps caused by extreme weather, grid failures, and periods of low wind or cloudy days.
In order to compete with traditional power plants, Chiang’s method needed to achieve a storage cost of around $20 per kilowatt-hour, which is one-tenth of the cost of lithium-ion battery storage.
The challenge was to transition from expensive batteries with short discharge times to an undefined, affordable, longer-duration technology.
In the 1980s and 1990s, the introduction of lithium brought about a significant change in batteries, making them smaller, lighter, and with longer-lasting charge.
The storage systems developed by Form Energy are rechargeable batteries based on iron, which offers various advantages over lithium, particularly in terms of cost.
Chiang, who previously expressed his fondness for lithium-ion batteries, founded two out of four MIT spinoffs focused on innovative lithium-ion technology.
However, the high cost and limited storage capacity of lithium-ion batteries made them unsuitable for Chiang’s current vision.
Chiang aimed to develop a cost-effective approach that would enhance the appeal of renewable energy.
The goal was to make solar and wind energy dependable for a large number of consumers by storing it for longer periods to bridge gaps caused by extreme weather, grid failures, and periods of low wind or cloudy days.
In order to compete with traditional power plants, Chiang’s method needed to achieve a storage cost of around $20 per kilowatt-hour, which is one-tenth of the cost of lithium-ion battery storage.
The challenge was to transition from expensive batteries with short discharge times to an undefined, affordable, longer-duration technology.
“Iron is produced, mined, and processed on every continent,” Chiang says. “The Earth is one big ball of iron.
We wouldn’t ever have to worry about even the most ambitious projections of how much storage that the world might use by mid-century.
” If Form ever moves into the residential market, “it’ll be the safest battery you’ve ever parked at your house,” Chiang laughs. “Just iron, air, and water.”
Reversible rusting is the term used by scientists to describe the process in which a battery takes in oxygen and converts iron to rust during discharge.
When an electrical current is applied, the rusty pellets can be converted back to iron, and the battery releases oxygen as it charges.
According to Chiang, in chemical terms, the iron becomes iron hydroxide, indicating that electrons were extracted.
These electrons are then used to power the external circuit, effectively creating a battery.
Form Energy’s battery modules are similar in size to a washer-and-dryer unit and are stacked in 40-foot containers.
Multiple containers are connected with power conversion systems to create storage plants that can cover several acres.
Teaching the utilities
The modules appear different and behave differently than what utilities have previously contracted for.
One of the main challenges for Form Energy is the lack of widespread awareness about the need for new tools to support decarbonized grids.
Traditional utilities typically rely on existing tools and may not consider multi-day energy storage assets in their planning. Form Energy’s customers are mostly traditional power companies transitioning to renewable energy and seeking low-cost multi-day storage solutions.
The company’s research provides valuable data for power suppliers looking to integrate renewable energy in a cost-effective manner.
Form Energy’s technology can complement existing systems and compete with other technologies, offering a unique solution within a cost-effective range.
Thanks to a fortuitous encounter, Form Energy has a significant lead over other companies in addressing this challenge. In June 2023, the company secured its largest deal to date with Georgia Power, and is now building a new commercial-scale battery manufacturing facility in West Virginia to meet the increasing demand.
This initiative not only addresses the need for energy storage but also creates new jobs in the clean tech sector, particularly in an area that has experienced significant job losses in the steel industry.
Source Deborah Halber for MIT News.
