Are solar panels worth it for my home?

How much the panels make

Each panel here is a typical modern 435-watt panel. How much electricity it makes in a year depends mainly on where you live and which way the roof faces. Southern England gets around 1,000 kWh a year for every kilowatt of panels, and northern Scotland nearer 820. A south-facing roof is best. Computer modelling with the European Commission’s PVGIS tool, reported by iHeat, puts south-east and south-west roofs at about 93 to 95% of a south-facing one, east and west at about 76 to 79%, and north at about 49%.

Where the savings come from

Electricity you use as it’s made saves you the full price, currently 26.32p per kWh under Ofgem’s price cap for October to December 2026. Spare electricity goes to the grid, and your energy company pays you for it under the Smart Export Guarantee. Being at home in the day means you use more of it yourself, and a battery stores the spare for the evening.

What it costs

The Energy Saving Trust puts a typical 3.5 kW system at around £7,000. Larger systems cost less per panel, because scaffolding and labour are shared. The estimate here is a guide; get at least three quotes from MCS-certified installers.

VAT is changing

Solar panels and batteries fitted by an installer have 0% VAT until 31 March 2027. From 1 April 2027, VAT goes up to 5%, which adds about £350 to a £7,000 system.

The 25-year figure

Panels usually last 25 years or more. The 25-year gain allows for panels producing about 0.5% less each year, a replacement inverter (around £800 after about 12 years, according to the Energy Saving Trust) and, if you add one, a replacement battery after about 12 years. It assumes today’s electricity prices; if prices rise, you save more.