Commercial solar panel installation — FAQs

UK commercial solar installation costs range from £700/kW for very large (1MW+) ground-mount projects to £1,200/kW for smaller (50-100kW) rooftop installs. A typical 100 kW commercial system costs £80,000-£120,000 fully installed including DNO application, structural design, MCS sign-off, and 25-year warranty. Battery storage adds approximately £700 per kWh of storage. Most projects are funded outright via capital purchase, asset finance over 5 years, or zero-capital PPA.

From signed contract to energised system typically takes 8-16 weeks for a roof-mounted commercial install. The phases are: design and DNO application (3-5 weeks), procurement and lead times (4-6 weeks), on-site install (2-4 weeks for a 100-300 kW system), and commissioning (1 week). Larger projects above 500 kW or those requiring planning permission can take 4-6 months end to end.

Payback periods on commercial solar in the UK range from 4 to 9 years, depending on self-consumption ratio, DNO export agreement, and capital cost route. A factory or hospital with continuous shift demand and 90%+ self-consumption typically pays back in 4-6 years. A warehouse or office with weekday-only demand and 50% self-consumption pays back in 7-9 years. Battery storage shortens payback for sites with high evening or weekend demand.

Most commercial roof-mounted solar installations are permitted development under Class J of the General Permitted Development Order, provided the panels do not project more than 200mm above the roof slope. Ground-mounted arrays above 50 kW require full planning permission. Listed buildings require listed building consent regardless of size; a conservation area alone does not. Your installer should handle any planning applications as part of the standard service.

Size commercial solar to consumption rather than to roof. A typical UK business uses around 50,000-200,000 kWh per year and needs a 50-200 kW solar system to offset 60-80% of grid imports during daylight hours. A good installer pulls your half-hourly meter data, models the system against actual demand, and recommends the size that maximises self-consumption rather than the largest system the roof can support.

The main UK commercial solar incentives are: the Annual Investment Allowance (100% first-year capital deduction up to £1m on solar PV as plant and machinery) and Smart Export Guarantee income for exported electricity. Farm solar grants in England have closed: round 2 of the Improving Farm Productivity grant (25%) closed in July 2025 and FETF 2026 closed on 12 May 2026. The Industrial Energy Transformation Fund (IETF) closed in July 2025 with no successor. The Public Sector Decarbonisation Scheme (PSDS) has had no open application window since November 2024 — Phase 4 was its final phase — so public bodies now rely on capital budgets, PPAs or leases. A Power Purchase Agreement removes the upfront cost entirely.

Solar panels are warranted for 25-30 years and typically retain 87%+ of rated output at year 25. End-of-life recycling is governed by WEEE regulations — PV Cycle UK and the European PV CYCLE programme manage commercial panel take-back. Panel glass and aluminium frames are recycled at 95%+ rates. Check whether PV CYCLE collection is included in the installation contract.

Yes — single-skin or composite metal roofs are the most common UK commercial substrate and pose no installation barrier. Installers use non-penetrating clamp systems (S-5! or RBR rail) to avoid roof penetrations and preserve membrane warranty. Standing seam, trapezoidal, and Kalzip profiles all have proven mounting solutions. Older corroded metal roofs may need refurbishment first — a good installer flags this at the desk feasibility stage.

The guides cover factories, warehouses, schools, hotels, hospitals, churches, farms, data centres, offices, retail showrooms and mixed-use commercial buildings. Each property type has its own guide with system sizing, payback models, grants and worked examples. Typical projects sit between £30,000 and £1m in capital cost.

Battery storage is increasingly common in UK commercial solar projects, particularly where the demand profile doesn't match generation (weekday-only sites, 9-5 offices, retail with evening peaks). Adding a battery typically costs £700-£900 per kWh of storage and shortens payback by 1-2 years for sites where time-of-use tariff arbitrage and resilience are valued. For sites with continuous demand (factories, data centres, hospitals), batteries are often unnecessary.

Look for MCS (Microgeneration Certification Scheme) Contractor accreditation as the baseline. Above that, NICEIC or NAPIT for electrical work, RECC (Renewable Energy Consumer Code) membership, TrustMark Government Endorsed, and the IWA (Insurance-Backed Warranty Authority) backed warranty. For larger commercial projects, ISO 9001 quality and ISO 14001 environmental management are standard. Our partner installer network holds all of the above.

Start with a desk-based feasibility. An installer needs three things: your half-hourly meter data (your supplier will email it on request), roof drawings or a recent satellite view, and an indicative demand profile. From those they produce a sized system, indicative cost, payback model and recommended finance route — usually within a week, with no fee or commitment. Use the quote form on this site and we reply by email.

South-facing roofs are optimal but east, west, and even due-north arrays are commercially viable in the UK. North-facing arrays produce around 65% of south-facing yield — still profitable on long-life systems where the marginal panel cost is low. East-west splits are common on flat roofs as they double the installable capacity and flatten the daily generation curve, often producing better payback than south-only arrays of half the size.