About Solar Payback Calculator

Estimate how many years home solar panels take to pay for themselves, using published electricity prices and solar generation data for the US and UK.

What it does

The calculator answers one question: if you put solar panels on your home, how long until the electricity they save you has paid back what they cost? It works for homes in the United States and the United Kingdom, in dollars or pounds, and shows a year-by-year breakdown over 25 years.

It starts from published figures for typical electricity prices, household use and local sunshine, so you get an answer straight away. Every starting figure can be replaced with your own: the numbers on your bill and on your installer’s quote will always give a better estimate than a national average.

What it leaves out

The calculator is deliberately cautious. It counts only electricity your home no longer has to buy, and values anything sent to the grid at zero. It does not include payments for exported power, grants, financing costs or maintenance. The methodology lists every simplification.

Guides

Our guides for US homeowners explain how payback is calculated, how much panels degrade over time and when a home battery pays off, with worked examples produced by the same calculator.

How the numbers work

The calculator runs entirely in your browser. It combines the figures you enter with published data. Every data point links to its source and shows the date we last checked it: see the methodology.

If we cannot verify a figure, we leave it out rather than guess.

Who runs this site

This site is run by Muneeb Tariq.

Get in touch

Spotted an error or out-of-date figure? Contact us.