Tests of the “world’s largest” thermal energy storage system have been completed

The system has an energy storage capacity of 10 MWh (electricity). It uses the heat generated by one of the gasworks blocks to heat concrete blocks that store thermal energy. This thermal energy is then returned to the power plant by converting the feed water into steam to produce electricity.

EPRI (Electric Power Research Institute) is an independent, not-for-profit organization that conducts research on the electric power system and is owned by public utilities. Southern Company is the gas and electric utility that owns the Gaston Power Plant through its subsidiary Alabama Power, and Storworks is the project supplier for the concrete thermal energy storage used in the project.

The project successfully carried out over 80 energy charging and discharging cycles, resulting in a total of over 700 hours of operation. For the purposes of the pilot, it was temporarily integrated with the installation. The project goals were exceeded by demonstrating steam production at several pressure levels.

“Advances in long-term energy storage (LDES) are key to unlocking the full potential of variable renewable energy resources on the path to net-zero energy,” said Neva Espinoza, EPRI vice president for energy supply and low-carbon resources. “As the energy sector undergoes a highly complex transformation, CTES can play an important role in efficiently delivering the reliable and affordable electricity that society depends on.”

The project received federal funding from the U.S. Department of Energy (DOE) under award DE-FE0031761.

Industrial heat accounts for a huge share of global greenhouse gas (GHG) emissions for heavy industry, which makes thermal energy storage a huge opportunity as well as a challenge for decarbonization. Thermal energy storage can either store heat for conversion back to electricity or supply this heat for industrial needs.

This week, Saudi oil giant Aramco signed a memorandum of understanding with heating brick company Rondo to decarbonize its global operations. At the end of April, a MW-scale molten salt hydroxide energy storage project was launched in Denmark, also the first of its kind in the world, according to technology supplier Hyme.

Two months earlier, Antora, a thermal energy storage startup, raised $150 million to commercialize its technology that uses heat stored in blocks of carbon material.