Distribution centre solar: your questions answered

It depends on roof condition, array size, grid connection and the scope of the quote, so there is no single price. Compare at least three written quotes on cost per kW; the cost guide shows how. Capital allowances apply: the Annual Investment Allowance up to £1m a year, then a 50% first-year allowance.

Array size depends on usable roof area, structural capacity, the daytime load and the grid connection, so size it from half-hourly meter data and a roof survey rather than floor area. The binding constraint is rarely roof area; it is usually the grid connection or the structural loading.

Often yes. Landlord consent is required. PPA structures shift the lease risk to a third-party owner. The BBP Green Lease Toolkit sets out lease clauses for these points.

It should, by design. The clearances come from the LPC and insurer standards for the building, with the insurer's sign-off before fabrication. The layout should be built around the sprinkler heads and access routes, not the other way around.

A proper design follows BS EN 1991-1-4 (Eurocode 1) for the specific site's wind exposure. Ballasted systems are weighted for worst-case wind uplift.

Often yes. Roof work happens above the operation, so MHE, picking and despatch can continue. The main operational impact is usually the final grid connection, which can be planned for a weekend or shutdown. Ask any supplier how it would phase the work around peak season.

A site that uses most of what it generates avoids buying at the full electricity price on more units and exports less at the lower Smart Export Guarantee tariff. A 24-hour load such as refrigeration or automation therefore tends to shorten payback. The size of the effect depends on your load, tariff and installed cost, so ask for the assumptions behind any payback or IRR figure.

Solar should not interfere, but check with the audit body, because requirements differ by standard and customer. Metered solar generation is evidence of reduced purchased electricity (Scope 2).

A site inside a designated Freeport tax site may claim a 100% first-year allowance on new plant; being in a Freeport city is not enough. Freeport eligibility should be checked for every applicable site.

Yes, it can work well for depot operations. Daytime EV charging uses solar on site rather than exporting it. Charging load and PV should be modelled together from half-hourly data.

Usually, because leases normally restrict alterations to the roof. The Better Buildings Partnership (BBP) Green Lease Toolkit sets out lease clauses for tenant-installed solar; landlords differ in what they accept. Time required: this varies by landlord, so ask early.

Own (cash or asset finance): you own the asset, claim the capital allowances that apply, and keep all kWh savings. PPA: third-party owns and operates; you pay per kWh consumed at a rate below grid retail; zero capex; off-balance-sheet. PPA is often the right choice for tenants on shorter leases, ownership for owner-occupiers.

Lease addendum should specify: (a) tenant removes the system at expiry (typical for short leases); (b) tenant transfers ownership to landlord at agreed value; or (c) PPA continues with successor tenant. The BBP toolkit covers all three.

No. The temporary 0% rate covers residential accommodation and, from 1 February 2024, buildings used solely for a relevant charitable purpose. A commercial roof pays 20% VAT, which a VAT-registered business making taxable supplies can usually reclaim. See HMRC VAT Notice 708/6 and take advice on your own position.

Because solar PV is normally special-rate plant. Full expensing is the 100% first-year allowance for main-rate plant. Solar gets the Annual Investment Allowance (100% up to £1m a year, shared with other plant spend and associated companies) and a 50% first-year allowance above that, so a project above £1m is not written off in one year. Check the position with your accountant and the HMRC capital allowances guidance.

Yes. It closed in July 2025 and no successor fund is planned; the last application window shut on 19 April 2024, and solar PV was never an eligible technology. Older guides that describe it as open are out of date.

Often not in England. Rooftop solar PV on non-domestic buildings is permitted development under Class J of Part 14 of the GPDO 2015, within limits on height above the roof and distance from the roof edge, with listed buildings and scheduled monuments excluded, and a roof array needs prior approval of its design or external appearance, in particular glare. Wales and Scotland have their own permitted development rights, which differ, and Northern Ireland has a separate system, so check the current local text.

Above 16 A per phase. A G99 application to the distribution network operator is required for generation above 16 A per phase (3.68 kW on a single phase); smaller generators use the G98 notification route. The DNO sets the connection terms, and its current timescales are on its own website.