Toolkit

All calculators

Every assumption is editable. Results update live — no submit buttons, no installer lead forms.

Estimate simple payback and 25-year net gain from a rooftop PV system with transparent assumptions.

Size a PV array from annual consumption, target offset, and local specific yield.

Work out whether a home battery pays back by capturing more of your own solar.

Compare annual running costs using SCOP, boiler efficiency, and fuel prices.

Calculate home EV charging cost with day/night tariffs and compare to petrol.

Build a list of household appliances and see annual electricity cost by device.

Estimate payback for loft, cavity, draught-proofing and glazing with multiplicative savings.

Split usage across peak, off-peak and night bands and rank up to three tariffs.

Convert freely between kilowatt-hours, cost and CO₂ using editable grid intensity.

Tip: start with solar payback, then size and battery tools if you need them.