Dive Brief:

• The U.S. Department of Energy's Office of Fossil Energy and Carbon Management is investing $2.4 million in three projects that are exploring the potential of energy storage technologies to shrink the carbon footprint of existing fossil fuel plants.
• The technologies — including high-temperature thermal energy storage and hydrogen storage — could help bolster grid reliability and affordability, while also potentially supporting the Biden administration's goal to decarbonize the electric grid by 2035, according to DOE.
• As the grid is increasingly powered by non-emitting resources, storage will play a role in matching variable generation with load, Haresh Kamath, the Electric Power Research Institute's program manager for energy storage, said. "This [effort] puts it in place in locations already connected up to the grid" and creates a pathway for these assets to be transitioned from fossil fuels to storage, he added.

Dive Insight:

The Office of Fossil Energy and Carbon Management's energy storage program is aimed at including energy storage technology research into the office's current portfolio in an effort to get the most out of the country's fossil fuel facilities. The DOE in early 2020 also launched its Energy Storage Grand Challenge, an effort to "accelerate the development, commercialization, and utilization of next-generation energy storage technologies and sustain American global leadership in energy storage."

Storage technologies can play a key role in helping the power sector use its existing assets more efficiently, as well as establish a good pattern for the grid as it becomes increasingly powered by non-emitting resources, Kamath said. 

The DOE's broader investment includes nearly $800,000 in funding for a sand thermal energy storage pilot design in which EPRI will participate. The pilot includes putting together a pre-front end engineering design study for a 10 MWh sand thermal energy storage system at a natural gas and coal plant in Alabama. 

EPRI's pilot is based on a thermal storage mechanism that can be either integrated into a conventional fossil fuel plant or operated independently, Kamath said. It works by using the heat from a thermal plant to heat water, and then running the steam through a fluidized sand bed, in an insulated area, that stores the heat for a long time. This system offers the advantage of being a fraction of the cost of conventional batteries, Kamath said. Moreover, it can be integrated directly into a fossil fuel plant, and lower its carbon footprint in both the near and longer term.

"In the near term, we can operate the plant at its most efficient point," thereby reducing the carbon generated per kilowatt-hour, Kamath said. 

In the longer term, the system can also be heated using renewable electricity rather than fossil fuels, Kamath said. 

"The nice thing about this is… you're basically building off of the existing infrastructure of the coal plant, so you don't have to build a whole new apparatus," he said.

The agency is also earmarking roughly $800,000 apiece for two other pilots: a study of a steel-concrete composite hydrogen energy storage prototype that can be integrated into coal and gas-powered electricity plants, as well as a hydrogen storage demonstration, based on producing hydrogen using natural gas coupled with carbon capture and storage.