Thermal technology that targets the storage of renewable energy resources is being advanced by U.K.-based Caldera. The heat battery system developed by the startup takes renewable solar and wind energy from the grid and stores 100 kWh as heat for up to 23 days. The heat can be delivered on an as-needed basis to both central heating systems and hot water supplies in the absence of real-time energy.

Initially developed for domestic heating applications, the Warmstone heat battery is now being scaled up for industrial heat requirements and to accelerate industrial decarbonization. The storage boiler will use intelligent circuitry to enable smart switching from grid to solar or other low carbon sources. Each unit will comprise 10 solid heat cells, each of which can store 200 kWh to offer a total of 2 MWh storage. These modular units can be scaled up to deliver as much capacity as needed, providing heat as hot water or steam.

Source: Caldera

Each heat cell houses a solid core of scrap aluminum and either basalt or granite encased in vacuum insulation, which can store heat at temperatures from 200° C to 500° C. The systems can be set to charge from the grid at night when cheaper and greener electricity is available, and can use on-site renewables, such as solar or wind.