Oct 30, 2020
By Mark Golden
The Precourt Institute for Energy’s Stanford StorageX Initiative is expanding its work beyond batteries to other means for storing electricity, such as in heat, carbon-neutral fuels and physical mechanisms.
Since the StorageX Initiative launched in the fall of 2019, its work focused on electrochemical cells, like lithium-ion batteries and competing rechargeable cell technologies, but the goal was always to broaden its perspective to energy storage broadly. The popular, online StorageX International Symposium series has turned its attention to non-battery technologies. On Oct. 2, its guests Prof. Thomas Jaramillo of Stanford University and Prof. Sossina Haile of Northwestern University discussed using renewable electricity to produce hydrogen and other fuels, and how fuel cells can efficiently convert those liquids back into electricity when needed. On Oct. 30, Prof. Robert Laughlin of Stanford and Andrew Ponec, ’17, discussed their technologies based on storing excess electricity in the form of heat.
This stationary fuel cell power system converts fuel into electricity, on display at an ARPA-E Innovation Summit. (Credit: Simon Edelman, U.S. DOE)
As for research, StorageX has funded early-stage projects to advance battery technologies, optimization, re-use and recycling, as well as the environmental impacts of battery production and disposal. The initiative leadership plans to provide research seed grants for some non-battery technologies next year. They will request proposals from Stanford faculty members in the late winter or early spring.
“We have always recognized that batteries will not be the energy storage solution for all applications,” said Yi Cui, co-director with Will Chueh of the StorageX Initiative. Both are professors in Stanford’s Department of Materials Science & Engineering.
“This is especially true for large-scale, long-duration energy storage to support the electric grid, where production costs are even more important than they are for mobile applications like electric vehicles and consumer devices,” said Cui.
Grid-scale storage of excess solar and wind power requires cost to be as low as possible to keep people’s electricity bills low, but the size and weight of such stationary systems are not as important as they are for EVs. Stationary storage has been one of StorageX’s nine focus areas since its inception. In addition to hydrogen production and fuel cells, the initiative’s work may focus on pumped hydro storage, compressed air and massive liquid-metal flow batteries to support the grid.
“One can think about using hydrogen as an energy storage medium, where an electrolyzer is used to make hydrogen from water, and running the electrolyzer in reverse then converts the hydrogen back to electricity,” said Chueh. “Like batteries, that’s a research area of real strength here at Stanford.”
Another of the initiative’s focus areas is understanding how energy storage integrates into energy infrastructures. StorageX will use technical, economic and life cycle analyses, as well as environmental impact assessments to discern what types of technologies may be most promising for various energy storage needs.
The Bath County Pumped Storage Station in Virginia is described as the “largest battery in the world.” It can generate 3,000 megawatts, enough electricity for about 2 million homes, for eight hours at full capacity.
One of the initiative’s grand challenges is long-duration energy storage. The requirements for success in addressing grid-scale storage, for example, vary a lot based on duration: whether saving from day to night or from summer to winter, or having enough storage to power a metropolitan area hit by a hurricane for several days or a week. This research and discussion could help guide research agendas at Stanford and elsewhere.
“For all the researchers out there, I think it’s really worthwhile to think about the economics,” said Chueh during the Oct. 2 StorageX Symposium. Laughlin strongly echoed that advice during the Oct. 30 symposium.
At a Stanford Global Energy Dialogue in June, Stanford professor and former U.S. secretary of energy Steven Chu predicted that a combination of new mechanical and thermal technologies could provide enough energy storage to enable electric grids to handle a broad reliance on intermittent solar and wind power. Small, modular pumped-hydro technologies under development could avoid the high hurdles for permits faced by large pumped-hydro facilities. Compressed-air energy storage technologies using hollowed-out salt caverns with isothermal energy transfer also are being seriously considered, Chu said.
Stanford StorageX Initiative brings together Stanford researchers and global industrial, government and academic collaborators. It is supported by its affiliate and sponsored research members.