Our Mission
Caldera are a British manufacturing start-up. We are here to reduce the use of fossil fuels, and our ground-breaking Warmstone heat battery was created to help you do just that.
Homeowner?
Warmstone is a heat battery. It warms up using electricity, storing energy until it is needed to provide heating and hot water. Designed for retro-fit in existing homes, it is particularly well suited to homes with oil boilers or solar panels.
Steam User?
Caldera's forthcoming storage boiler will help manufacturers and food processors decarbonise process heat and steam. By maximising the use of renewables electricity they reduce exposure to fluctuating fossil fuel prices.
Future Investor?
We are proud to be backed by a community of nearly 1,300 Crowdcube investors. If you would like to join our journey to net zero heat we would love to welcome you when we next raise money. Register now so we can keep you informed.
Three Breakthroughs
Caldera's unique technology delivers breakthrough performance while using readily available and non-toxic materials.

Core Material
- Non-toxic, recyclable materials
- High energy density
- Safely heated to 500C
- Patented
Insulation System
- Stores heat for weeks
- Keeps surface cool
- Designed to last decades
- Patent pending
Heat Extraction System
- Consistent output temperature despite core varying by hundreds of degrees
- Creates hot water or steam, as desired
- Patent pending
Powered by Renewables
Warmstone uses low carbon electricity whenever the wind is blowing or the sun is shining, then stores the energy efficiently until it is needed.

Featured On:





Meet the Team














