Zero Carbon Boiler

Our Warmstone Zero Carbon Boiler has sufficient power and energy to heat your home and provide hot water with the same level of comfort and convenience as an existing oil or gas boiler.

Zero Carbon Boiler

A Zero Carbon Boiler consists of two elements. The first is a Warmstone Heat Battery located externally to the property. The second is a Heat Interface Unit that replaces the existing boiler.

The heat battery can be charged with low cost electricity from the grid. In the UK today there are three electricity suppliers offering 5p/kWh off-peak tariffs.

You can store and use electricity from your own solar PV panels to reduce or eliminate your hot water bills during the summer months. 7kW of additional PV can be fed directly to the unit without restrictions.

Warmstone Heat Battery

The heat battery is located externally or in a garage, preferably near to the current boiler location.

It weighs 1.5 tonnes and holds enough energy to heat a standard home for 24 hours in winter.

Charging is achieved with electric resistance heaters to store the energy as heat, which can be supplied to your home on demand.

We use high quality insulation to minimise losses with a target of less than 10% energy lost over the year.

Heat Interface Unit

The Heat Interface Unit replaces the boiler with the same functionality.

It can be installed as a straight boiler ‘swap out’.

The system delivers the same level of thermal power (30kW) and comfort as your existing boiler.

Installation can be carried out by your existing plumber without having to upgrade the radiators or change the piping runs within your home.

Journey to Zero Carbon:

Renewable electricity has significantly depressed wholesale electricity pricing in the first 6 months of 2020 while lowering the carbon intensity of electricity to just 165g CO2/kWh. This compares against heating oil (320g CO2/kWh) or natural gas (210g CO2/kWh). A carbon intensity of 34g CO2/kWh was achieved on the UK grid on 23rd May 2020. Most importantly low electricity prices always tend to occur when the electricity is also low carbon.

The Zero Carbon Boiler can move heating and hot water demand to match the periods when renewables are generating (low carbon and low prices). This supports the roll out of renewables by providing essential flexible demand and balancing services to the grid. It also means that the carbon intensity of the electricity used to provide heat will approach zero over time.