Solar Cost Calculator
UK yield ≈ 850–1,000 kWh per kWp/year depending on region and orientation.
Result
Annual generation4,000 kWh
Bill saving£437.50/yr
SEG export income£337.50/yr
Total annual benefit£775.00/yr
Payback10.3 years
25-yr benefit£11,375.00
Solar Cost Calculator — FAQs
How many panels is 4kWp?
Roughly 9–10 modern 430W panels — about 18–20 m² of roof. UK roofs typically fit 4–6kWp on a 3-bed.
Is north-facing worth it?
Yields ~65% of south — often still pays back, but slower. East/west split arrays are the better compromise for dual-aspect roofs.
Battery worth adding?
A 5kWh battery (~£3k) lifts self-consumption from ~50% to ~80% — worth it if your usage is evening-heavy and you're on a cheap overnight tariff to charge it.
Going Solar?
We model roof generation and tariff mixes before you commit to install costs.
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