Distribution Centres: Solar panels for industrial units

Why a distribution centre is the best industrial unit you can put solar on

If you run a distribution centre you are sitting on the single most valuable solar asset in the UK industrial estate: a massive, clear-span steel-portal roof with almost nothing on it. Across the country, logistics buildings hold more than 600 million square feet of roof that earns nothing today, and a regional DC is usually the largest single industrial unit in any business park. That roof is structurally sound, free of plant and rooflights across most of its span, and oriented for daytime generation, which is exactly when a busy DC draws its load. Materials handling equipment charging, dock levellers, high-bay lighting and battery rooms all pull power through the working day, so the electricity your panels make is consumed on site at retail-displacement value rather than exported for a few pence. Self-consumption is the single biggest driver of solar payback, and a well-run DC typically uses the great majority of what a roof array generates. That is the core of the case for putting solar on an industrial unit of this kind: the demand and the generation line up, and the roof was already paid for.

Network charges are the other half of the story. TNUoS and BSUoS have risen 40 to 80% since 2022, and for a logistics P&L that is a direct, uncapped hit that no amount of operational efficiency fully offsets. Solar is one of the few levers a distribution centre operator genuinely controls: a one-off investment that fixes a large slice of your import bill for two decades, immune to wholesale volatility and rising standing charges. On top of that, customer Scope 3 mandates now flow straight through to the buildings that fulfil them. Amazon's Climate Pledge, Tesco's net zero supplier programme and Unilever's CTAP all push emissions expectations down to the DC, and on-site generation is auditable evidence of Scope 2 reduction that increasingly appears in contract-winning audit packs through CDP Supply Chain, EcoVadis and contractual SLAs. For a distribution centre, solar is both an overhead cut and a commercial differentiator, and the underused roof estate means every quarter without it is leaving money on the table.

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 clear-span 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. On an industrial unit of this scale, roof area is almost never the binding constraint. Sizing is driven by your daytime baseload and your DNO connection capacity, so we never simply fill the roof. We pull your half-hourly meter data and look at the real shape of the day, because many DCs have a surprisingly low daytime baseload between order peaks, and an oversized array that exports cheaply is worse than a right-sized one that displaces import at full retail value. The M1, M6 and A1 corridor sites are our highest-priority builds because the roofs are large, the loads are real and the grid is often better provisioned.

For a distribution centre that runs on a single daytime shift, batteries are increasingly economic at scale, shifting midday generation into the early evening despatch peak and capturing more of the array on site. For 24-hour operations the case for storage is weaker, because consumption already tracks generation closely. We model both scenarios from the same half-hourly data and tell you which adds value for your operation rather than defaulting to a battery on every quote. A modern logistics building of 100,000 to 500,000 square feet can typically accommodate 1 to 5 MW of rooftop PV, so the question is rarely whether the roof can take it, but how much of it your load and your connection can sensibly use.

Costs, payback and tax relief

A distribution centre project typically lands between £350,000 and £2.4m depending on roof area and system size, at roughly £700 to £900 per kW, with a simple payback near 5.5 years and the electricity effectively free for the fifteen to twenty plus years after that. At scale, large DC roofs often reach £600 per kW or below. The biggest financial lever is tax. Solar PV qualifies as plant and machinery, so the 100% Annual Investment Allowance lets most companies write off the cost up to the annual cap against profit in year one, worth up to a quarter of the project value back as tax saved for a limited company, with a 50% First Year Allowance available on qualifying spend above the cap, subject to current legislation. For 24-hour or shift operations export is minimal and the return is driven by avoided import, which is the better position to be in. Where you do export surplus, the Smart Export Guarantee pays 4 to 15p per kWh as of 2026.

How you fund the system changes the shape of the return rather than whether it pays. Buying outright, with cash or asset finance, means you own the asset, claim the full tax allowances and keep every kilowatt-hour of saving. A power purchase agreement instead puts a third-party owner on your roof: they fund and operate the array and you pay per kWh consumed at a rate below grid retail, with zero capex and the arrangement off-balance-sheet. PPA is often the right choice for tenants on shorter leases, ownership for owner-occupiers with a long horizon. Our cost guide sets out worked numbers by system size and compares ownership against a PPA so you can see the difference for a DC at your scale.

Funding routes in detail

Most distribution centre installs are fully expensed in year one under the Annual Investment Allowance, and combined with PPA finance the tax shield can become a negotiation point with tenants or operators. If your building sits within a designated Freeport or Investment Zone, such as Freeport East at Felixstowe and Harwich, Liverpool City Region, Teesside, Solent, Thames, Humber or East Midlands, it may qualify for 100% Enhanced Capital Allowances on new plant and machinery, so we check Freeport eligibility for every applicable site because the prize is effective full first-year tax relief on qualifying capex. For tenant-occupied DCs, the Green Lease route matters more than any grant: it is not money, but it unlocks your ability to install solar on a leased building at all. We work to the Building Better Partnership Green Lease Toolkit, the industry standard, and provide the lease addendum template aligned with it, then engage your landlord directly to obtain consent.

Timescales for that consent vary: typically four to eight weeks for institutional landlords such as Prologis, Tritax, Blackstone and GLP, who mostly hold standard green-lease addenda, and one to four weeks for owner-occupied or family-owned property. Pure logistics 3PL generally falls outside the Industrial Energy Transformation Fund, but food-warehouse operations within scope should still check, since the IETF runs a 30 to 50% intervention rate on a £100k to £30m band through DESNZ. The full picture, including how these routes stack, is on our funding page.

Compliance and sector considerations

On a distribution centre, sprinkler clearances are mandatory and non-negotiable: we design to LPC clearance standards, 1m to the deflector and 0.6m at high-bay, and the PV layout is built around your sprinkler heads and emergency access routes, not the other way around. Insurer engagement is essential, and the large-roof PV risk profile is now well defined, so we obtain insurer pre-design review and sign-off before anything is fabricated, working to the specific PV criteria that the major insurers all now publish. Most warehouse PV proceeds under permitted development through Class A Part 14 of the GPDO 2015, listed building and conservation issues are rare for logistics, and a G99 grid application applies above 17 kW per phase, with installs over 1 MW often needing a bespoke DNO study and contestable connection works.

Wind loading is the other technical point on a tall DC roof. Every install is designed to BS EN 1991-1-4, Eurocode 1, for the specific site's wind exposure and terrain category, and ballasted systems are weighted for worst-case uplift, so a high roof is a design input rather than an obstacle. Tenant capital improvement clauses in the lease also need addressing early, which is where the green-lease work begins, and fire detection integration to BS 5839-1 is coordinated where the PV ties into existing alarms. None of this is exotic on a logistics building; it is simply the standard envelope, and we work inside it as a matter of course.

How we approach this kind of project

We start with your half-hourly meter data, not a roof drawing, because on an industrial unit the load curve tells us the right size far better than the square metres do. We size for self-consumption first, model export and any battery only on the surplus, and we submit the G99 grid application early so the connection clock starts while the structural and roof survey runs. We check the roof build-up, fixings and any plant penetrations before we commit to a fixed-price proposal, so the number you sign is the number you pay, with no day-of-install surprises. For tenant-occupied buildings we engage the landlord directly with the BBP addendum and manage the consent process for you.

Every install is delivered above your live operations, so picking and despatch continue normally throughout, and the only outage is the final grid synchronisation of four to eight hours, scheduled for a weekend or planned shutdown. We have delivered installs through peak season with zero operational impact where clients have asked. The workmanship is covered by a ten-year insurance-backed warranty, and the whole programme runs through MCS, NICEIC, RECC and TrustMark certified delivery. The aim throughout is a roof that quietly cuts your overhead and stands up in a customer audit without ever interrupting the despatch schedule.

An illustrative example

As an illustrative composite based on typical UK distribution centre projects: a national 3PL operating a 280,000 square foot distribution centre near Daventry, serving major UK retail chains, was paying around £620,000 a year for power and held a 15-year FRI lease with green-lease provisions. The design came in at about 1.18 MW, roughly 2,170 panels, generating in the region of 1,090,000 kWh a year. Funded through a PPA with zero capex, self-consumption sat near 84%, the saving was around £245,000 a year for a payback close to 5.1 years, and the customer audit pack now included auditable Scope 2 reduction, with a phase two across two further DCs in scoping. The figures are illustrative and depend on your roof, tariff, lease and load profile.

If your estate also includes shared-customer or shift sites, our pages on solar for fulfilment centres and cold storage warehouse solar may also apply. When you are ready, see the cost guide and funding routes, then request a free feasibility from your meter data, or read the industrial unit solar FAQs first.