Commercial Solar London — FAQs

Between £750 and £1,200 per kWp fully installed, depending mainly on system size and access. A 50kW hotel or office system typically lands at £46,000–£57,000; a 250kW industrial system at £185,000–£235,000. The premium over national pricing is 5–15%, driven by access logistics rather than hardware — and offset by the capital's higher electricity rates.

Four to six years for most well-sized systems, and faster for seven-day operations. London paybacks beat the national average despite higher install costs because each generated kWh displaces more expensive grid power — many central London businesses pay 26–30p/kWh on current contracts.

Usually not — permitted development covers most commercial rooftop installs. The London exceptions are real, though: conservation areas, listed buildings and certain protected settings need case-by-case checks. Every project should start with a written planning screen; ours is included in desk feasibility.

UK Power Networks (UKPN) is London's distribution network operator. Commercial systems need a G99 application before connection: typically 4–8 weeks for smaller systems, 8–12 for larger ones needing a network study. Submitted early, it runs in parallel with surveys and procurement and never blocks the programme.

As a rough screen: every 100 square metres of clear, unshaded roof supports about 20kW, and 20kW in London generates roughly 17,000 kWh — worth £4,000+ a year at city rates with high self-consumption. Small London systems on expensive power regularly out-earn bigger systems elsewhere. Below about 15kW of viable space, the fixed costs usually outweigh the return.

Yes, with the landlord's consent, and consent is increasingly forthcoming because the EPC benefit lands on the landlord's asset. The clean routes: a licence to alter for occupier-funded systems, or a roof lease where a funder owns the array. Sort the lease paperwork before design — it changes what should be built.

Surplus generation exports to the grid and earns export income — typically 4–12p/kWh in 2026 under SEG-style arrangements. Because export is worth far less than on-site use, systems are sized so weekday consumption absorbs most generation. A five-day London office still typically self-consumes 70–85% across the year.

It works; it just covers a smaller share of the load. A tower roof might host 30–50kW against a very large building demand — high-value generation and a useful EPC contribution, but not a transformation. We model it honestly and will tell you if scaffolding costs outweigh the achievable system.

Storage costs £350–£550 per kWh installed at commercial scale and earns its keep only where export share is high or tariff spreads are steep. Most London commercial buildings self-consume so much of their generation that batteries are a phase-two question. The half-hourly model answers it definitively either way.

Minimal when planned properly. Roof work proceeds above business-as-usual; the single planned interruption is a connection shutdown of a few hours, scheduled out of hours. Hotels install in low season; offices connect at weekends; industrial sites work around shift patterns. The logistics plan handles deliveries, parking suspensions and access.

Modest but real: monitoring response, an annual electrical inspection, inverter health checks, and cleaning matched to the site — London traffic film and rail-corridor dust mean every 12–24 months for most flat-roof arrays. Budget £8–£15 per kWp per year. Inverters are the consumable: one replacement around years 10–14.

No general grant exists in 2026, from the GLA or nationally — treat anyone claiming otherwise with suspicion. The real support is tax-shaped: the Annual Investment Allowance gives a 100% year-one deduction on qualifying spend up to £1m, and solar qualifies for the 50% first-year allowance beyond that. Public-sector buildings have separate funding routes.

Indirectly but persistently. The target shapes borough planning policy, the London Plan expects renewables on major new commercial development (Policy SI 2), and the policy environment keeps tightening around building emissions — MEES being the sharpest current example. None of it compels an existing building to fit solar; all of it rewards the buildings that do.

Emphatically yes — piggybacking solar onto planned roof works is the cheapest install you will ever do. Re-roofing, plant replacement and major maintenance all put access equipment on site that solar can share. If roof works are on your 24-month plan, price the combined project; the access saving is typically five figures in London.

Three inputs: 12 months of half-hourly meter data, the building address, and roof drawings or photos. That produces a desk feasibility with system size, yield, indicative London pricing, planning screen and UKPN read — in writing, within 7 working days, without a site visit or a salesperson.