Why solar works in Cardiff
Cardiff is the capital of Wales, with a 2021 census population of 362,756 and the largest commercial office estate in the principality. Major employers concentrated inside the central business district include Admiral Group with its FTSE 100 headquarters at Capital Tower, Legal and General, the BBC Cymru Wales headquarters at Central Square, Principality Building Society, NHS Wales at the University Hospital of Wales, Cardiff University, and the Motorpoint Arena Cardiff.
PVGIS modelling for CF10 returns typical annual yields of around 940 kWh per kWp installed for a well-oriented rooftop array at 30 to 35 degrees pitch. In practice that means a 4 kWp domestic array generates roughly 3,760 kWh per year, and a 50 kWp commercial rooftop around 47,000 kWh.
Commercial solar in Cardiff
Densest commercial office-roof stock in Wales with MEES B-by-2030 driving demand. For commercial operators, the combination of a predictable 940 kWh/kWp yield, current commercial electricity prices at 28 to 32p per kWh, and the Annual Investment Allowance tax treatment means simple payback on a well-sized Cardiff commercial array typically lands between 3.5 and 6 years.
Worked example: 100 kWp commercial installation
- Installed cost: approximately £85,000 to £95,000
- Year-one generation: 94,000 kWh
- Typical self-consumption rate against HH data: 65 to 80 percent
- Simple payback at prevailing electricity pricing: 3.6 to 4.5 years
- Post-tax payback with Annual Investment Allowance: 2.6 to 3.2 years
Typical Cardiff commercial rooftops
We have installed commercial solar across Capital Waterside, Cardiff Central Enterprise Zone, Cardiff Business Park Llanishen and other industrial estates in Cardiff. Typical system sizes range from 30 kWp on smaller trade units to 500 kWp-plus on larger warehouse and factory roofs.
Domestic solar in Cardiff
For Cardiff homeowners, a typical domestic installation is a 4 to 5 kWp array paired with a 5 to 10 kWh battery. At 940 kWh/kWp, a 4 kWp system generates around 3,760 kWh in year one, which covers a meaningful share of a three or four-bedroom household's annual consumption once battery storage smooths the time-of-use mismatch. Payback typically lands at 7 to 10 years at current pricing and Smart Export Guarantee tariffs.
Planning and grid connection
The planning authority for Cardiff is Cardiff Council. Rooftop solar PV on commercial buildings almost always falls within permitted development under the Town and Country Planning (General Permitted Development) (Wales) Order, subject to the usual 200 mm projection limit and non-listed, non-scheduled-monument conditions. Properties inside a conservation area will typically require full planning permission; we handle the application end-to-end.
For grid connection, systems above 3.68 kW per phase require a G99 application to the DNO. Typical approval timelines are 6 to 8 weeks for Type A (up to 1 MW), which we lodge concurrently with design and procurement so they do not sit on the critical path.
Why FLD for your Cardiff installation
- NICEIC Approved Contractor under a single sign-off for both solar and electrical works
- MCS certified for both PV and battery, which is essential for Smart Export Guarantee eligibility
- Swansea-based, directly employed engineers, not subcontractors, on every site
- Insurance-backed NICEIC warranty plus 25 to 30-year panel performance warranty from tier-1 manufacturers
- Remote monitoring included as standard so generation and performance are visible from day one
Start the conversation
If you own a commercial rooftop or a domestic property in Cardiff (CF10, CF24, CF11) and want a realistic assessment against your actual consumption data, call Paul direct on 01792 680611 or visit our Cardiff location page for full local detail.
