Truro and Cornwall sit in the UK's highest solar yield zone — 10% above the national average. The far South West has the longest sunshine hours in mainland Britain. A 4kW system here generates around 3,740 kWh a year. Cornwall's large proportion of rural homes, many off the gas grid, make it one of the UK's strongest markets for combined solar and heat pump adoption.
Select all that apply if your panels will span multiple roof faces.
Already have a battery or thinking of adding one? Include it to see how it affects your payback.
Generation uses a UK baseline of 850 kWh per kWp installed, adjusted for your region's solar irradiance, roof orientation, pitch and shading. South-facing roofs at 30–45° hit the baseline; east/west takes a 15% hit; north loses a third.
Self-consumption defaults to 40% without a battery — the rest exports to the grid. A battery raises self-consumption progressively up to 80% at ~15 kWh capacity.
Savings = self-consumed kWh × your import rate, plus exported kWh × your SEG rate. Apply 0.5% panel degradation per year over the 25-year warranty.
Install cost reflects 2026 UK ranges with 0% VAT (in force until April 2027). Battery cost: roughly £350/kWh installed plus a £2k base.
This is an estimate. Actual generation and quotes vary — get a site survey from an MCS-certified installer before committing.
Use the official MCS register to find certified solar installers in your area. MCS certification is required for SEG payments and grant eligibility.
◐ Always get at least 3 quotes · Check reviews on Trustpilot and Google
Are you an MCS-certified installer? Get listed on Knowwatt →