Free solar panel calculator.Will solar pay off for your roof?
Type your address and see what panels on your roof would generate, save and pay back: sunshine data for your exact location, your country's electricity and export prices, and the incentives you can actually claim.
Always free for homeowners. No sign-up, no email wall, no sales calls.
Free, no sign-up, no email wall. Payback, NPV, IRR and CO₂ on real PVGIS data.
What the calculator tells you
One address, six answers. Everything below comes from a single calculation for your roof.
How much power your roof makes
Yearly and month-by-month generation in kWh for your system size, tilt and direction, so you can see the winter dip as well as the summer peak.
What it saves you each year
Year-one savings from the power you use yourself and the surplus you send to the grid, each priced at your country's electricity and export rates.
When it pays for itself
Simple payback in years, plus a 25-year cashflow that includes electricity price rises and panel ageing, not just a single optimistic number.
Whether it beats leaving the money in the bank
Net present value and internal rate of return, the same measures an investor uses, so you can compare solar with other uses of your savings.
Which incentives apply
National grants, tax credits and VAT relief are applied where they exist, and named in the result, so you can see what moved the number.
Whether a battery is worth it
Compare the same roof with and without storage side by side. A battery raises how much solar you use yourself, and we count what it costs.
Where the numbers come from
A solar estimate is only as good as its inputs. These are ours.
Sunshine for your exact location
Generation comes from PVGIS, the European Commission's Joint Research Centre solar model, for your coordinates, including shading from surrounding terrain. NASA POWER data fills the few places PVGIS does not cover.
Your country's real prices
Electricity prices, export and feed-in rates and installed cost per kWp are researched per country from regulators and national statistics, and dated so they can be re-checked.
Incentives you can actually claim
Only current schemes are applied. Where a scheme has ended, we remove it rather than keep a flattering number.
Stated as an estimate
Every result shows its assumptions. It is a careful estimate for deciding whether to get quotes, not a quote: an installer who sees your roof will be exact.
Want the detail? Read what payback, NPV and IRR really mean or how to read a solar quote.
Not a lead form in disguise
Many solar calculators exist to collect your phone number. This one exists to answer the question.
If you do want quotes, there is an optional form under your result. Leaving it empty changes nothing.
Solar calculator by country
Prices, export rules and incentives differ a lot between countries. Each page shows what a typical home system produces, saves and costs there in 2026.
For installers and developers
The same engine is available as a calculator widget for your own website, with quote requests sent to you, and as a REST API for building it into your product.
Check your own roof in a minute
Your address, your system size, your country's prices. Free, and nothing to sign up for.