The widget is built for UK readers: they pick their region and system size, say whether they're adding a battery, and get three numbers back. Nothing else to fill in, no email capture, no pop-ups.
Add it to your site
Copy this and paste it into the HTML of your page — any content management system that lets you edit source or add a custom HTML block will take it.
<iframe src="https://uksolarcalc.co.uk/embed-savings-calculator" width="100%" height="520" style="border:1px solid #e5e7eb;border-radius:12px" loading="lazy" title="Solar savings calculator by uksolarcalc.co.uk"></iframe>
It is responsive: the calculator fills whatever column you put it in. In a narrow sidebar, give the iframe a bit more height (try height="620") so the results have room to stack.
Good to know
If you would rather credit us in your own text
Some publishers prefer to keep the credit in their own page copy rather than inside the widget. This line does the same job — put it under the calculator, or anywhere in the article:
<p>Solar savings calculator by <a href="https://uksolarcalc.co.uk/savings-calculator">uksolarcalc.co.uk</a></p>
Where the numbers come from
- Sun hours — PVGIS 5.2 regional averages from the European Commission's Joint Research Centre. These are net generation figures (kWh per kWp per year), so inverter, shading and temperature losses are already included — no separate derate is applied.
- Electricity price — Ofgem's default-tariff price cap, 26.32p/kWh for 1 October to 31 December 2026, reviewed every quarter.
- Export income — a typical 6p/kWh Smart Export Guarantee rate. Supplier-set and genuinely varies, so the widget quotes a mid-market figure.
- System cost — about £1,600 per kW installed, with 0% VAT on residential solar and storage in Great Britain until 31 March 2027. A 5 kWh battery is costed at £4,000 and lifts self-consumption from 45% to about 75%.
The full method, including the degradation and electricity-inflation assumptions behind the 25-year figure, is documented on our methodology page. If you want a deeper version for your own readers, our main savings calculator adds their monthly bill, a cost breakdown and a 25-year cashflow explanation.
Something not working?
Email [email protected] with the page URL and we will take a look. If you would like a different default region, a different colour scheme or a second widget, tell us — we add widgets when a publisher asks for one.