Calculate your solar panel cost
Solar panel cost by system size in Cardiff
Terraced home · UK solar £6,000£5,850
2–3 bed / semi-detached · UK solar £8,000£7,800
Small detached · UK solar £9,000£8,800
Large detached · UK solar £10,000£9,800
Solar plus battery examples
Battery benchmark £4,500£10,350
Battery benchmark £8,000£15,800
Battery benchmark £9,000£17,800
Battery benchmark £10,000£19,800
How the moderated solar factor works
What can change a real Cardiff quote?
- Solar PV capacity in kW
- Panel and inverter specification
- Roof orientation, pitch and usable area
- Scaffolding and access
- Battery capacity in kWh
- Electrical upgrades and monitoring
- Roof condition and structural suitability
Local planning considerations
For grants and energy schemes, verify the current Wales-specific eligibility rules before relying on any support assumption.
- Use Wales-specific planning, building-control and energy-scheme information where the rules differ from England.
- Terraced or constrained urban properties can add access, waste and scaffold costs that are not captured by the regional factor.
- Drainage, roof and external-work scopes should be based on the property condition rather than a generic city assumption.
How the regional model works
The broad Wales factor is 0.91×, but solar uses a moderated 0.978× factor to match the live calculator. Only one quarter of the regional difference is applied to the solar-only benchmark, while battery storage remains at the national equipment benchmark.
Sources
Solar Panel Installation: Cost Breakdown 2026
Published / checked: June 2026
Used for: 3–6 kW solar PV and battery storage benchmarks
Frequently asked questions
How much do solar panels cost in Cardiff in 2026?
Current UK solar-only benchmarks are £6,000 for 3 kW, £8,000 for 4 kW, £9,000 for 5 kW and £10,000 for 6 kW. The model gives about £7,800 for 4 kW in Cardiff.
How much is a 4 kW solar system with an 8 kWh battery in Cardiff?
The national example is £8,000 solar plus £8,000 battery. The model adjusts only the solar component, giving about £15,800.
Why is the solar regional adjustment smaller than the general Wales factor?
Solar contains a large equipment component that is less locally variable than labour-heavy building work, so the calculator applies only one quarter of the broad regional difference.
What can make a solar installation more expensive?
Roof access, scaffolding, electrical upgrades, inverter specification, battery capacity, roof condition, structural work and complex panel layouts can increase the total.