Typical cost in 2025
Most homeowners pay around £6,500 for a 10-panel (3.5kWp) system, supply and fit, no battery
What affects the price?
Number of panels
A typical home uses a 10–14 panel system (3.5–5kWp). More panels = more electricity generated = higher upfront cost but better long-term return.
Battery storage
Adding a solar battery (e.g. Givenergy, Tesla Powerwall) costs an additional £2,500–£5,000. Batteries let you store excess generation for use in the evening rather than exporting it.
Roof type and access
South-facing, low-pitch roofs are ideal. East/west-facing systems still work well. Flat roofs need ballasted mounting frames (extra £500–£1,000). Slate roofs require specialist fixings.
Scaffolding
Required for most installations. Typically included in the installer's quote but adds £600–£1,200 to the overall job cost.
Inverter type
String inverters (cheapest, less flexible) vs microinverters (more expensive but better for shaded roofs). Budget £600–£1,500 for the inverter depending on type.
Typical cost breakdown
Estimates are based on UK average rates in 2025. Prices in London and the South East are typically 20–30% higher.
Frequently asked questions
How long do solar panels take to pay for themselves?
Typically 8–12 years depending on your energy usage, roof orientation, system size, and whether you have a battery. With rising energy costs, payback periods are getting shorter.
Do I need planning permission for solar panels?
In most cases no — solar panels on houses fall under permitted development. Conservation areas and listed buildings are exceptions. Always check with your local authority if unsure.
How much electricity can solar panels generate?
A 10-panel (3.5kWp) system generates approximately 3,000–3,500 kWh per year in the UK — enough to cover 70–90% of an average household's electricity use.
What is Smart Export Guarantee (SEG)?
SEG pays you for surplus electricity you export back to the grid. Rates vary by supplier (4–15p/kWh). With a battery, you export less and use more of what you generate.
Do I need MCS-certified installers?
Yes — to claim SEG payments and access certain grants, your installer must be MCS certified. Always check before hiring.