The house was built in the 1930’s, but when Mary and John moved in they were determined to lower their energy footprint. Insulation in the loft and an internal wall insulation have reduced heat loss, and roof ‘lanterns’ make use of natural lighting.
A 25 kW biomass pellet stove provides hot water and cooking, and new double glazing has sustainable oak frames.
They installed solar photovoltaic panels using SolarEdge technology to optimise output when the panels are partly shaded. The electric car is charged on sunny days from the electricity generated, topped up at night using off-peak rates.
A Tesla Powerwall battery storage was installed several years ago to make use of electricity generated during the day, through the night.
Electricity to the house is provided by a 100% renewable supplier. The supply is controlled by aTesla Virtual Power Plant. This enables Tesla to choose when to buy and sell electricity to the grid, and when to charge up the car and the Powerwall battery. This reduces the energy price supplied to the house to around 12p/unit, as well as paying the same rate for excess electricity exported.
This summer a bank of solar thermal ‘tubes’ was installed reducing the energy requirement to heat the domestic water. To top this up, the immersion heater is controlled by a switch which can be turned on/off and a timing sequence set by a smart phone app.