Building a long-life grid battery
We’ll need to increase renewable energy use by 430% this decade to get on track to net zero. But the sun sets and the wind stops blowing, so we’ll also need battery storage to keep up with demand — and in fact, we need new kinds of batteries, Protocol’s Lisa Martine Jenkins writes.
What’s wrong with lithium-ion grid storage? Utility-scale versions of those ubiquitous batteries can only discharge energy for up to four hours at a time, meaning that systems can falter when the grid needs to provide widespread power for a long period of time.
- To free the grid from fossil fuels that currently provide a baseload of energy, we need long-duration batteries that provide power for at least several days at a time.
- In reality, of course, we’ll need both: fast-reacting batteries such as lithium-ion, as well as something that can discharge over a longer period.
A potential solution uses alternative chemistry. A company called Form Energy is developing batteries that use an iron-air technology, its CEO, Mateo Jaramillo, told Lisa.
- These batteries work by harnessing the power of rust: They submerge a piece of porous iron in an electrolyte solution, using the metal’s rusting process to charge and discharge energy over the course of several days.
- This technology has been around for decades and was the subject of a 1970s Department of Energy study. But in Jaramillo’s view, it is only now ready for commercialization because the technology is particularly well-suited to the demands of today’s — and tomorrow’s — grid.
The new batteries are now being tested: Form Energy signed a partnership with Georgia Power, its first with an investor-owned utility, earlier this year. The duo will work to deploy up to 15 megawatts of storage capacity. (In 2020, it announced a much smaller 1 megawatt pilot project with the Minnesota cooperative Great River Energy.)
- The company recently closed a $450 million Series E funding round, bringing its total pot of funding to $800 million. It counts high-profile VCs like Bill Gates’ Breakthrough Energy Ventures and Energy Impact Partners among its investors.
But even if they work, the batteries face obstacles to deployment. Markets need to be redesigned to reflect “where we really are today and where we want to go,” Jaramillo said. “Grid operators and markets were designed with an entirely different and largely combustion-driven grid in mind.”
