US storage developer Antora Energy announced on 1 October 2026 that it will build a 5.8 GWh multi-day thermal storage — or heat battery — project at the Pratt Energy biorefinery in Pratt, Kansas. Once complete, the installation is expected to rank among the largest battery energy storage systems in the world.
The system uses carbon blocks heated to 2,400°C to store energy for multiple days, and will supply stable, cost-competitive industrial heat to the biorefinery. That end use distinguishes it from most LDES projects, which target the power sector.
Why industrial heat is the overlooked LDES market
Industrial process heat is difficult to decarbonise because it requires high temperatures and continuous supply, and because electrification options such as resistance heating expose the plant to wholesale power prices. A thermal store that charges on cheap or curtailed renewable electricity and discharges heat on demand decouples the plant's energy cost from real-time market volatility.
Thermal storage converts an intermittent electricity input into a firm, dispatchable heat output — effectively turning a biorefinery's energy supply into a controllable asset rather than a price-taker.
Scale as a statement
At 5.8 GWh, the Antora project dwarfs most grid batteries being commissioned today, which typically deliver a few hundred megawatt-hours. Duration is the differentiator: multi-day storage is designed to bridge extended periods of low wind and solar output, a role currently filled largely by fossil gas plants.
The announcement lands in a crowded month for long-duration storage manufacturing and deployment. Italy's Energy Dome opened a new manufacturing plant in Piacenza on 8 October, focused on volume production of core carbon-dioxide storage equipment including large gas-holding domes, for projects in India, the US and Ireland. A 1 GWh iron-air system promising nearly 100 hours of discharge was also unveiled in late October.
What to watch
For Antora, the commercial test will be whether the Kansas installation delivers the promised availability and heat cost against a gas-fired baseline. For the wider sector, projects of this size provide the operating data that financiers need before underwriting thermal storage at scale — and evidence that LDES demand extends well beyond the electricity grid.
This article was assisted by AI analysis. Please refer to the original source for official information.