This tool estimates the annual benefit of a home solar installation — electricity you don't buy, export income, and EV miles charged from your roof — and divides it into the up-front cost to give a payback year. Generation figures are regional averages derived from the EU PVGIS solar database for a well-oriented roof; your roof's pitch, direction and shading will move the answer. For the reasoning behind the EV assumptions, read our solar charging guide.

How you'll use the energy

Generation used in the home (%):

EV miles charged from solar per year:

Your daytime import rate (p/kWh):

Rate you'd otherwise charge the EV at (p/kWh):

Export rate (p/kWh):

Results

Notes: generation degrades slightly over time (panels are typically warranted to ~87% output after 25 years) and electricity prices change, so treat the payback year as an estimate, not a promise. Batteries usually carry a 10-year warranty — if your payback is longer than that, budget for a replacement. The EV line values solar-charged miles at the difference between solar charging and your night rate; if you don't have an EV tariff yet, fix that first — it's free and saves more than the panels do. See the tariff guide.

EV COST CHECKER

Solar & battery payback calculator

Results