Solar Panels for Businesses — UK Buyer's Guide

Commercial solar panel installation for UK businesses, explained. Free matched installer quotes.

Why businesses are well-suited to commercial solar PV

UK businesses represent a strong commercial solar PV market on their fundamentals. A typical business site of the scale this guide covers consumes substantial daytime electricity — process loads, HVAC, lighting, refrigeration, IT — with demand profiles that map well onto solar generation curves. Unlike domestic PV, where most generation is exported, commercial sites in this sub-vertical typically self-consume the majority of generated solar electricity, dramatically improving project economics.

A typical commercial solar system for businesses is 20-200 kW, with around 60 panels covering roughly 180 sqm of usable roof area. Capital values run £25k-£220k, payback typically lands at 6 years on capital purchase, annual generation of 19,000-190,000 kWh per year, and CO2 savings of 4-39 tonnes per year.

Typical businesses system sizing

Most commercial solar PV systems for businesses sit between the lower and upper bounds of the 20-200 kW range, with the precise sizing driven by half-hourly meter data analysis rather than roof capacity alone. The right principle is to maximise self-consumption — there is no economic value in installing capacity that exports under SEG at low marginal rates when that same capital could be deployed elsewhere or saved entirely.

Three sizing dimensions matter most. First, the host's annual import volume — the aim is for the array to offset 50–90% of daytime imports without significant export. Second, the roof's useful area — accounting for plant, edge zones, fire breaks, and shadowing. Third, the DNO export agreement and any G99 connection constraints — good installers size systems to demand, not to export, and apply export limiting where required.

Cost and payback for businesses

For a typical 20-200 kW businesses commercial solar install, capital cost in 2026 ranges between £25k-£220k. Cost per kW falls as system size rises — sub-100 kW installs typically cost £900–£1,200 per kW fully installed, 100–500 kW falls to £750–£950 per kW, and systems above 500 kW can come in below £800 per kW.

Payback for businesses typically lands at 6 years on a capital purchase basis with a self-consumption ratio of around 80%. Faster payback (4–5 years) is achievable on continuous-shift sites with very high self-consumption; slower payback is typical of weekday-only sites with high export. Asset finance over 5 years is typically EBITDA-positive from month one. Power Purchase Agreement (PPA) funding removes upfront capital entirely.

For full UK-wide cost data and worked financing examples, see our commercial solar cost guide and commercial solar grants and funding overview.

Compliance and regulation for businesses

Compliance for commercial solar in this sub-vertical extends beyond the technical install scope. Every project must hold MCS contractor certification, G99 grid connection approval from the local DNO, BS 7671 18th Edition electrical compliance, full structural calculations to BS EN 1991, and CDM 2015 principal designer and principal contractor coverage. Insist on a single accountable contract — one principal contractor, one G99 application, one structural sign-off, one insurance-backed workmanship warranty.

Funding and grants applicable to businesses

Several UK funding routes apply to businesses solar projects. Annual Investment Allowance gives all UK limited companies 100% first-year capital deduction up to £1m. The Public Sector Decarbonisation Scheme historically covered up to 100% of capital for public-sector estates but has had no open window since November 2024 (Phase 4 was final). The Industrial Energy Transformation Fund (IETF) closed in July 2025 with no successor fund, so it is no longer a route for manufacturers. PPA funding requires zero capital from the host. A desk feasibility should map the right combination of these funding routes to the project.

How a businesses commercial solar project runs

Every businesses project follows the same phased approach. Phase 1 is desk-based feasibility — the installer pulls your half-hourly meter data and roof drawings, models the system in PVSyst and shares an indicative proposal, typically within a week. Phase 2, if the numbers work, is a 1-day on-site structural and electrical survey followed by a fixed-price proposal. Phase 3 is permits, DNO application, structural sign-off, and any grant paperwork — typically 6–12 weeks. Phase 4 is on-site installation — 2–10 weeks depending on system size. Phase 5 is commissioning, monitoring activation, and handover.

Typical businesses install — at a glance

• System size: 20-200 kW
• Panels: 60
• Roof area: 180 sqm
• Project value: £25k-£220k
• Payback: 6 years
• Annual generation: 19,000-190,000 kWh
• Annual CO2 saved: 4-39 tonnes