U.S. Secretary of Energy Jennifer M. Granholm today announced the U.S. Department of Energy’s (DOE) goal to reduce the cost of grid-scale, long-duration energy storage (of which pumped storage hydro is the largest source) by 90% within the decade.

The second target within DOE’s Energy Earthshot Initiative, “Long Duration Storage Shot” sets goals to accelerate breakthroughs that store clean electricity to make it available anytime, anywhere and support more abundant, affordable and reliable clean energy solutions. 

“We’re going to bring hundreds of gigawatts of clean energy onto the grid over the next few years, and we need to be able to use that energy wherever and whenever it’s needed,” said Granholm. “That’s why DOE is working aggressively toward cheaper, longer duration energy storage to reach President Biden’s goal of 100% clean electricity by 2035. This new initiative will create new manufacturing jobs right here at home and make sure clean, reliable, affordable electricity is available to everyone, including Americans living in remote and underserved communities.”

Long-duration energy storage – defined as systems that can store energy for more than 10 hours at a time – would support a low-cost, reliable, carbon-free electric grid. Cheaper and more efficient storage will make it easier to capture and store clean energy for use when energy generation is unavailable or lower than demand – for instance, so solar-generated power can be used at night.

Developing the technology and manufacturing to reach the Long Duration Storage Shot cost targets will also establish a new, U.S.-based manufacturing industry and union jobs for storage products, DOE said. And energy storage can increase local control of the power system and build resilience for communities, including by minimizing power grid disruptions.

“Energy storage technology holds great promise in the fight against climate change. Strengthening current technology and advancing next-generation energy storage will allow us to integrate more renewables, such as wind and solar, which in turn will help to reduce emissions,” said U.S. Senator Susan Collins. “That’s why I authored the Better Energy Storage Technology Act, which seeks to align U.S. research efforts to promote advancements in energy storage technologies. It is exciting to see the Department of Energy begin implementing this new law through this initiative to substantially reduce the cost of energy storage technologies, improve the efficiency of our nation’s electricity grid, and bring us closer to a clean energy future.”

The Long Duration Storage Shot will consider all types of technologies –electrochemical, mechanical, thermal, chemical carriers, or any combination that has the potential to meet the necessary duration and cost targets for grid flexibility. Pumped-storage hydropower is the largest source of long-duration energy storage on the grid, and lithium ion is the primary source of new energy storage technology deployed on the grid in the U.S., providing shorter duration storage capabilities.

DOE developed the Long Duration Storage Shot target through its Energy Storage Grand Challenge (ESGC) and stakeholder engagement activities and input from subject matter experts.