How much do solar panels cost?

£5,500-£8,000 for a 4kW system at 0% VAT. Adding battery: +£4,000-£6,000.

How much do they save?

£580-£1,100/year depending on battery and tariff. Over 25 years: £14,500-£27,000.

How long do they last?

25-30+ years. Inverter replacement at 10-15 years (£800-£1,500). Panels keep working at 80-87% after 25 years.

Do they work in the UK?

Yes — 1.3 million homes prove it. UK receives enough sun for strong returns everywhere.

Do I need planning permission?

Usually no — permitted development for most homes. Conservation areas/listed buildings may need permission.

What is the payback period?

8-12 years. After payback: 15+ years of essentially free electricity.

Is a battery worth it?

Standalone: marginal payback (18yr). With Octopus Flux: strong payback (8-10yr). Best for evening self-consumption and tariff arbitrage.

0% VAT (everyone), SEG income (everyone), ECO4 (low-income), BUS grant (heat pump). No general grant for most.

Solar Panel FAQs UK

By Home Solar Guide Team|Updated 18 March 2026|guide

Independently written | Evidence-based | Sources cited

Solar panel FAQs — The 25 questions we hear most — all answered in plain English with evidence.

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What are the most common solar panel questions?

Top 5 solar FAQs: (1) Cost? £5,500-£8,000 for 4kW at 0% VAT. (2) Savings? £580-£1,100/year. (3) Payback? 8-12 years. (4) Do they work in UK weather? Yes — 1.3 million UK homes prove it. (5) Do I need a battery? Optional — adds £200-£400/year savings at £3,000-£7,500 cost. See all 25 FAQs below for the complete picture.

Frequently Asked Questions

Related: Home Heating Systems

Solar panels are most powerful when combined with an efficient heating system. Heat pumps use solar-generated electricity to heat your home at 300-400% efficiency — making them the ideal partner for solar.

heat pump running costs in the UK

Heat pumps use electricity at 300-400% efficiency, making them ideal partners for solar.

From our sister site Home Heat Pump Guide