Distribution Centres: Solar panels for distribution centres

Why a distribution centre is the strongest solar roof in UK logistics

A modern distribution centre is, in solar terms, close to an ideal building. The clear-span steel-portal roof runs to thousands of square metres with almost no obstruction, the structure is recent and well documented, and the daytime electrical load is large and predictable. Materials handling equipment charging, lighting across high-bay racking, conveyors, dock levellers and office and welfare loads all draw power through the working day, which is exactly when the panels are generating. That alignment matters more than anything else, because self-consumption is the single biggest driver of solar payback. A distribution centre that uses the great majority of what it generates rather than exporting it at a lower price will see a typical simple payback of around 5.5 years, and faster where shift patterns extend the day.

The pressure to act is no longer purely about the meter. Network charges, the TNUoS and BSUoS elements of an industrial bill, have risen sharply since 2022, putting a direct and growing dent in logistics P&L, and customer net-zero mandates now flow straight through to the operators and tenants who run distribution estate. When your contract counterparties include the major UK retailers, on-site generation stops being a nice-to-have and becomes auditable evidence of Scope 2 reduction that appears in their supplier scoring through schemes such as CDP Supply Chain and EcoVadis. For a logistics director or asset manager, fitting solar to a distribution centre is one of the few moves that improves the cost line, the carbon line and the contract position at the same time. The roof estate is sitting there regardless; every quarter it stays bare is generation, and tax relief, left on the table.

It is worth being honest about why these projects sometimes stall, because the obstacles are predictable and every one is now routine to clear. Many distribution centres are leased rather than owned, raising the question of consent and end-of-lease treatment; insurers have hardened their stance on large-roof PV after poor installs elsewhere in the market; and taking a live building offline feels risky to anyone responsible for despatch. None of these is a reason to do nothing, and the rest of this page is about how each is handled rather than left to chance.

What a typical install looks like and how we size it

For a distribution centre we usually design a system in the 500 to 3,000 kW range, which is roughly 920 to 5,500 panels across about 3,000 to 18,000 square metres of roof. A system that size generates in the region of 460,000 to 2.75 million kWh a year and saves somewhere between 106 and 633 tonnes of CO2 annually. To put that in building terms, a modern logistics shed of 100,000 to 500,000 square feet can typically accommodate 1 to 5 MW of rooftop PV. The thing we never do is simply fill the roof. On a distribution centre the binding constraint is rarely the roof area; it is the daytime baseload and the DNO capacity at your connection. Many warehouses retain generous existing grid capacity from past industrial heritage, but that always needs confirming rather than assuming.

We pull half-hourly meter data first, because a single-shift pick operation between order peaks can have a surprisingly low daytime baseload, while a busy multi-shift DC will carry a much higher one. MHE charging is the load that most reliably lifts daytime self-consumption, since the fleet plugs in across the working day exactly when generation peaks. We size for self-consumption against that real load curve rather than a theoretical maximum, and where the daytime profile dips between peaks we model whether a battery earns its place by shifting midday generation into the busier hours. For a 06:00 to 18:00 operation a battery is increasingly economic at scale; for a building that already runs into the evening it is often unnecessary because the load itself does the time-shifting. The sizing recommendation falls out of the data, not out of a template.

Costs, payback and tax relief

A distribution centre project typically lands between £350,000 and £2.4m depending on roof area and system size, which works out at roughly £700 to £900 per kW and falls towards £600 per kW or below on the largest schemes where scale brings the rate down. The simple payback sits near 5.5 years, and the electricity is then effectively free for the fifteen to twenty plus years after that. The largest financial lever is tax. Solar PV qualifies as plant and machinery, so the 100% Annual Investment Allowance lets a limited company write off qualifying cost up to the £1m annual cap against profit in year one, with a 50% First Year Allowance available above it under current legislation, worth up to a quarter of the project value back as tax saved in the first year. Most warehouse installs are fully expensed in year one under the AIA, and where a PPA is in play that tax shield can become a negotiating point between landlord, tenant and operator. For a 24-hour DC export is minimal because self-consumption dominates, but where the operation is closer to a daytime shift the Smart Export Guarantee pays 4 to 15p per kWh as of 2026 on any surplus you do send back to the grid. Our cost guide sets out worked numbers at different system sizes and per-kW rates.

Funding routes in detail

Most distribution centre installs are funded one of three ways, and the right one depends on whether you own or lease the building. Owner-occupiers usually buy outright or via asset finance and claim the full Capital Allowances (100% AIA up to the cap, 50% FYA above), which on a large DC can fully expense the capex in year one. Tenants on a lease more often choose a Power Purchase Agreement: a third party funds, owns and operates the array and you pay per kWh consumed at a rate below grid retail, with zero capex and the asset kept off your balance sheet, which is frequently the right answer for an operator on a shorter lease who does not want the building's solar on their own books.

The lease itself is unlocked through the Green Lease Clause and Tenant Capital Recovery route. Tenant-installed solar is now standard practice on UK logistics leases; the lease requires landlord consent, but most institutional landlords have standard green-lease addenda, and the Building Better Partnership Green Lease Toolkit is the industry standard. We provide the addendum template aligned to it and engage the landlord directly, so consent does not become your problem to project-manage; it typically takes four to eight weeks for an institutional landlord and one to four weeks for owner-occupied property. The addendum also settles the end-of-lease position up front, whether that is removal at expiry, transfer at agreed value, or continuation of a PPA with a successor tenant. Where the building sits inside a designated Freeport or Investment Zone, Enhanced Capital Allowances can give effective 100% first-year relief on qualifying plant, so we always check zone eligibility. The funding guide walks through each route in full.

Compliance and sector considerations

The compliance points that matter on a distribution centre are well defined and we design to them from the start rather than discovering them on site. Sprinkler clearances are mandatory, so the PV layout is built around your sprinkler heads to LPC clearance standards, one metre to the deflector and 0.6 metres at high-bay, not the other way around, with emergency access routes maintained per the fire risk assessment. Insurer engagement is essential; the large-roof PV risk profile is now well understood by the major insurers, several of whom operate their own specific PV criteria, and we obtain insurer pre-design sign-off before anything is fabricated rather than presenting them with a finished design after the fact. Where the building is leased, tenant capital improvements clauses in the lease govern what you may install, which is why the green-lease addendum is part of our standard package.

Beyond the sector-specific points, every install carries the usual structural and grid framework. Wind loading is designed to BS EN 1991-1-4, Eurocode 1, for the specific terrain category and exposure of your site, and ballasted systems are weighted for worst-case uplift rather than an average; most warehouse roofs sit comfortably inside the standard design envelope. A G99 grid application is required for connections above 17 kW per phase, and on a large warehouse the DNO study is something we treat as a programme item in its own right. Where fire detection is integrated we work to BS 5839-1 and SPF1981 v3 fire safety design, with BAFE SP203 certification where relevant. The work is delivered under MCS commercial certification, NICEIC, RECC and TrustMark, by a contractor running ISO 9001, 14001 and 45001. Most distribution centre PV falls under Permitted Development through Class A Part 14 of the GPDO 2015, and listed-building or conservation-area constraints are rare for logistics buildings.

How we approach this kind of project

Our approach is built to remove the things that usually stall a distribution centre project. We start with your half-hourly meter data so the system is sized to your genuine daytime baseload and self-consumption rather than to an optimistic roof-fill figure. We run roof and structural checks, including any historic roof penetration and condition questions, before we commit to a layout, and we resolve the sprinkler and insurer position in parallel so there are no surprises at fabrication. We submit the G99 grid application early, because on larger installs above 1 MW the DNO study and any contestable works are often the longest pole in the programme, and starting the clock at the survey stage protects your timeline.

You receive a fixed-price proposal rather than an open estimate, the workmanship is covered by an insurance-backed warranty, and the build itself happens above your operations so picking, despatch and MHE activity continue as normal. We do not take the building offline to install. The only outage required is the final grid synchronisation, typically four to eight hours, which we schedule for a planned shutdown or a weekend. The whole sequence is designed so that the decision to install never has to compete with the decision to keep despatching.

An illustrative example

As an illustrative composite based on typical UK distribution centre projects: a national operator running a 280,000 square foot distribution centre on the M1 corridor near Daventry, serving major UK retail chains and paying around £620,000 a year for power, fitted roughly 1.18 MW across the main roof, about 2,170 panels generating in the region of 1.09 million kWh a year. The scheme was funded through a PPA with zero capex, self-consumption sat near 84% against the daytime baseload, and the saving came to around £245,000 a year for a payback close to 5.1 years. The result fed straight into the customer audit pack as auditable Scope 2 reduction, and a phase two across two further sites went into scoping. The figures are illustrative and depend on your roof, load profile, tariff and funding route.

If your estate mixes pure distribution with third-party logistics or temperature-controlled storage, our pages on solar for fulfilment centres and cold chain warehouses may also apply. When you are ready, request a free feasibility from your meter data, see the cost guide or read the distribution centre solar FAQs first.