- Antora Energy will install a 5.8 GWh thermal battery at Pratt Energy’s Kansas biorefinery, one of the largest energy storage installations globally.
- The project will store low-cost electricity as high-temperature heat and supply continuous process energy under a long-term offtake agreement.
- Its commercial significance lies in targeting industrial heat, where thermal storage can avoid the cost and efficiency losses of converting energy back into electricity.
Antora Energy has announced a 5.8 GWh thermal battery project at Pratt Energy’s Kansas biorefinery, marking its second multi gigawatt-hour industrial heat development this year.
The system will store electricity as heat in insulated carbon blocks and deliver continuous thermal energy to the ethanol plant under a long-term heat offtake agreement. Energy deliveries are scheduled to begin next year.
Copenhagen Infrastructure Partners led the project’s third-party equity financing through its credit platform, with Australia’s Grok Ventures and University Pension Plan Ontario also participating. The project cost and power rating were not disclosed – Antora describes the system as multi-day storage, but its precise duration and thermal output remains unclear.
The development is expected to support more than 100 construction and operational jobs. Antora said it would use little additional water beyond the biorefinery’s existing requirements and would not materially increase noise for neighbouring properties.
Industrial heat as storage market
Antora’s system uses resistance heating to raise solid carbon blocks to temperatures of up to 2,400C. The stored energy is then transferred as radiant heat and used directly in industrial processes or to produce steam. The company is separately developing thermophotovoltaic cells that can convert light from the hot blocks back into electricity.
Direct heat use is commercially important because it avoids the conversion losses and additional equipment required to return stored heat to electricity. Industrial plants requiring steam or high-temperature process heat can instead use the battery as an electrically charged replacement for fossil fuel boilers.
Pratt Energy intends to use the project to improve the efficiency and carbon intensity of ethanol production. Antora said it could help the plant move towards zero carbon-intensity ethanol, although the actual emissions outcome will depend on the electricity used to charge the battery and the treatment of agricultural and supply chain emissions.
The project follows Antora’s commissioning of a 5 GWh system at Poet’s Big Stone City biorefinery in South Dakota. That development used more than 200 factory-built modules and began delivering energy less than 12 months after construction started.
The Big Stone project also required an innovative electricity tariff with Otter Tail Power. The tariff allows the battery to charge rapidly when surplus renewable power is available, while protecting other customers from the costs created by a very large new electrical load.
That commercial structure may be as important as the storage hardware. Thermal batteries are most competitive when they can access low-cost electricity during limited periods and convert it into round-the-clock industrial heat. Standard network charges or flat industrial tariffs can undermine that advantage.
Copenhagen Infrastructure Partners’ Reiner Boehning said Antora had demonstrated “sound technology, compelling economic fundamentals, and a clear path to repeatable deployment at scale”. Independent trade publication ESS News noted that the project follows a $550 million Antora fundraising and an expansion of its San Jose manufacturing facilities.
On an international level, food and drink, chemicals, paper and other steam-intensive industries could use thermal batteries to replace gas while absorbing renewable electricity that might otherwise be curtailed.
In the UK, the obstacle is the high industrial electricity price relative to gas. Successful deployment may require flexible network charging, long-term renewable contracts or tariffs that reward consumption during periods of surplus generation.
Antora’s second project suggests thermal storage is moving beyond demonstration scale. The next test is whether its economics can be replicated outside unusually favourable US electricity markets and biofuel plants, particularly in countries where policy still makes electricity an expensive way to produce heat.
