Antora Energy, a startup founded in 2018, has deployed a thermal battery system in South Dakota that stores energy as heat. The facility uses surplus electricity from nearby wind farms to heat carbon blocks to 2400°C. These blocks retain heat for several days, providing steam to a neighboring POET ethanol plant.
The system allows the ethanol producer to reduce natural gas consumption for its 177°C steam requirements. POET reports that the cost of steam from the Antora battery is comparable to natural gas, with the added benefit of qualifying for federal tax credits for low-carbon biofuel production.
Antora plans to scale its operations by manufacturing modules in factories for rapid on-site assembly. The company has already secured a contract to supply another thermal battery to Pratt Energy in Kansas. The technology is designed to serve various industrial processes, including cement and paper production.
Competitor Rondo Energy is also active in the sector, using firebricks heated to 1500°C. Rondo currently supplies steam to a biofuel plant in California and a cement factory in Thailand, with a future project involving a Heineken brewery in Portugal.
Despite the potential, the industry faces regulatory hurdles. Many regions lack flexible retail electricity tariffs, which are essential for charging batteries during periods of surplus, low-cost renewable energy. Companies like Antora must negotiate new rate structures with local utilities to ensure economic viability.
