Warmstone for Homes

Warmstone is the boiler replacement that makes it easy to cut your carbon. It delivers plenty of hot water, on demand and at the same temperature as the boiler it replaces, meaning no radiator upgrades or other disruptive building work is required.

Warmstone is a heat battery – it contains a core that heats up using electric elements similar to those found in a kettle. Vacuum insulation means this heat can be stored for up to 23 days.

As well as working in homes, Warmstone can also be used in other buildings such as offices and churches, where several Warmstone units can work together to provide as much thermal storage as is needed.

Cuts Carbon

Uses renewable electricity


Installed outside or in garage

Made in Britain

Built in our Hampshire factory

Heat & Hot Water

Same water volume and temperature as a boiler

Minimal Disruption

No new radiators or insulation


Non-toxic materials, recyclable at end of life

Compatible with most radiators

The Warmstone works with your current pipes, radiators or underfloor heating. As it produces water at the same temperature as your boiler there will be no change in comfort.

Heating Controls
Compatible with most controls

You can keep your existing thermostats and other heating controls. The Warmstone will work with traditional controls, or most smart thermostats.

Store your solar power

Warmstone is a great complement to solar panels (PV). Storing energy as heat means lower costs and capacities 7-10 times greater than that of a typical chemical battery. Advanced electronics mean every watt of spare solar can be used.

Many homes will have enough solar to provide free hot water throughout the summer, and Warmstone’s ultra insulation means it can smooth out dips in the weather. As a result you can enjoy a hot bath a week or more after a sunny day.

Switch from heating oil

Heating oil is expensive, inconvenient and high in carbon. We hear from many customers using heating oil, and also LPG, that they have had a quote to install a heat pump but the cost and disruption of the new heating system, insulation and radiators means it is not viable.

For these homes Warmstone is a great alternative. It can be fitted outside, and connected to the existing heating system to replace or complement a boiler. Water temperatures remain the same, so no other changes are needed.

How It Works

Icon of Warmstone core being heated
Core Heated

Electricity is used to heat the Warmstone’s core. Temperatures inside range from 200C to 500C.

Icon of heat being stored
Heat Stored

When the heating is turned on water circulates through the Warmstone and into the radiators and hot water cylinder.

Icon of heat being used
Heat Used

When the heating is turned on water circulates through the Warmstone and into the radiators and hot water cylinder.


Suitable Space

The Warmstone is large, so it is ideal for detached and semi-detached homes and is usually fitted in a garage or garden. It is fully weatherproof, and ultra insulation means cold has little impact on performance.


Hot Water Cylinder

The Warmstone is currently designed to work with a hot water cylinder. A combi boiler replacement that does not require one is planned in the coming years.

Powered by myenergi logo

Included with every Warmstone are sensors and controls provided by myenergi, a like-minded manufacturer and the makers of zappi, the best selling UK-made electric vehicle charger. The Warmstone is designed to charge as quickly as possible using all the electricity available. Intelligent controls constantly monitor how much power is being used, so if you put on the kettle while the Warmstone is charging it will turn down in a matter of milliseconds.

If you have other devices from myenergi, such as the zappi or eddi, they will be shown alongside the Warmstone in the app. This is available free from the Apple Store or Google Play.

Reserve Now

Thanks to extraordinary demand we are operating a waiting list. Register now so we can let you know when more units become available.


Warmstone Brochure

All information and specifications may change as we continue to evolve the Warmstone.