Solar for chilled distribution centres: refrigeration load and self-consumption

Why a cold store suits rooftop solar

If you operate a refrigerated distribution centre or cold store, you have one of the most constant daytime loads of any building, and the reason is simple. Refrigeration never stops. Compressors, condensers, fans and controls run 24 hours a day, every day, which means the electricity your panels generate is consumed on site at almost the moment it is made. Self-consumption on a cold chain facility is typically high, and because grid electricity is the largest single operating cost in temperature-controlled distribution, every kWh the panels displace lands directly on the bottom line. That combination of relentless demand and high power intensity gives cold storage a high share of self-consumption, which helps its payback.

There is a regulatory tailwind as well. The F-gas Regulations are pushing operators towards heat-pump and lower-GWP refrigeration retrofits, and solar pairs naturally with that shift because an electrified, more efficient cold chain has an even larger and steadier daytime electrical appetite for the panels to feed. For operators whose energy bill is the largest controllable line on the P&L, the return is worth modelling carefully against the board's payback test.

It is also worth naming the network-charge angle, because it bites hardest here. The TNUoS and BSUoS elements of an industrial electricity bill apply to every unit imported, and a cold store importing power around the clock feels that more than almost any other building. Every kWh the panels generate is a kWh not imported at those inflated rates, so the saving is larger per unit than on a daytime-only operation. That is the mechanism behind the sector's exceptional returns: it is not just that cold stores use a lot of electricity, it is that they use it continuously and at a moment when the cost of importing it has never been higher.

What a typical install looks like and how it is sized

Array size depends on usable roof area, structural capacity, the daytime load and the grid connection; PVGIS gives roughly 886 to 1,042 kWh per kWp per year across the cities we have checked, so annual generation is about that figure multiplied by the kWp the roof can take. Because the refrigeration load is constant and high, the sizing question is unusually clean: high self-consumption is comfortably achievable and frequently far higher, so the system can be sized aggressively against the around-the-clock baseload with confidence that almost everything generated will be used rather than exported at a lower price.

Still begin with half-hourly meter data to confirm the precise load shape, because even within cold chain there is variation, a blast-freeze operation behaves differently from a chilled ambient store, but on a cold store the daytime baseload rarely disappoints, which is exactly why these projects pay back so quickly. The roof area is almost never the constraint; the DNO connection capacity is the item to confirm, and many cold stores carry generous capacity from their refrigeration plant history. Where the operator is also planning an F-gas-driven plant upgrade, the future electrical load should be factored into the sizing so the array is not undersized against the building the cold store is about to become.

Costs, payback and tax relief

Payback depends on the installed cost and on how much of the output is used on site, so compare written quotes and ask for the assumptions behind any figure; the cost guide sets out the method. Cold-chain operators tend to self-consume most of what they generate because the avoided import is so large and so constant, which helps the return. Tax is the largest lever, as with any commercial install. Solar PV is plant and machinery and is normally special-rate plant, so the Annual Investment Allowance covers the first £1m a year of qualifying spend (a limit shared with other plant spend and associated companies), spend above it attracts a 50% first-year allowance, and full expensing does not apply. Because self-consumption on a 24-hour cold store is so high, export and therefore the Smart Export Guarantee play only a minor role, but the return is driven by avoided import, which is the stronger and more durable position. Our cost guide sets out how to read a quote.

Funding routes in detail

Cold chain operators have one funding route that other logistics buildings often do not, and it is worth real money. SIC-code eligibility should be checked as part of the project finance review rather than discovered later.

Owner-operators usually buy outright or via asset finance and claim capital allowances: the Annual Investment Allowance up to its £1m a year limit, then a 50% first-year allowance, so a project above £1m is not written off in one year. Tenants can fund through a Power Purchase Agreement with the lease enabled by the Green Lease Clause route and the BBP toolkit addendum. A site inside a designated Freeport or Investment Zone tax site may claim a 100% first-year allowance on new, unused plant used primarily in the site, with end dates set by HMRC, so check the site against the official designation before relying on it. The Smart Export Guarantee exists but plays only a minor role here, because a 24-hour cold store exports very little; the return is built on avoided import rather than export income, which is the more durable position. The funding guide explains which combinations stack for your circumstances.

Compliance and sector considerations

Two compliance points are specific to cold storage and the design should address both from the start. First, the F-gas Regulation 2014/517 governs the refrigeration plant, and because solar so often accompanies a refrigeration upgrade the PV is best coordinated with any F-gas-driven retrofit rather than treated as a separate job, so the electrical infrastructure is sized once for the combined future load. Second, roof penetration design must respect insulated panel integrity; a cold store roof is a structural insulated envelope, and any fixing detail has to preserve the thermal and moisture performance of that envelope, so mounting designs that minimise penetration and protect the insulation are favoured, because a compromised cold roof is far more costly than the saving from a cheaper fixing.

On top of these sector-specific points, the standard logistics framework applies: LPC sprinkler clearances with the array laid around the heads, insurer pre-design sign-off before fabrication, wind loading to BS EN 1991-1-4 for the site exposure, and a G99 grid application above 16 A (3.68 kW) per phase; BS 5839-1 applies where fire detection is integrated. Crucially for a cold-chain operator, solar supports rather than threatens the food-safety audits that govern the business. Customer and audit requirements differ, so check with the audit body; metered solar generation is evidence of reduced purchased electricity (Scope 2).

How to approach this kind of project

The cold-chain approach centres on protecting the envelope and the operation while capturing the exceptional economics. Start with half-hourly meter data to confirm the refrigeration baseload, then design a fixing and layout strategy that respects the insulated panel construction and minimises penetration of the cold roof. The sprinkler and insurer position should be resolved before fabrication, the G99 grid application submitted early so the DNO process runs alongside the build, and any F-gas-driven plant works coordinated so the two upgrades complement each other rather than competing for the same shutdown window.

A good proposal is fixed-price rather than open-ended, the workmanship should carry an insurance-backed warranty, and the install should proceed above the operation so the cold store keeps running at temperature throughout. The main outage is usually the final grid connection, which can be scheduled for a planned window. Where the operation qualifies, a project finance review should check Freeport tax-site status, and on a leased site the BBP-aligned landlord consent runs in parallel. The combination of a constant load and the same funding routes as other sites makes cold storage a strong solar case, provided the stock and the audit position are never put at risk.

If your estate also includes ambient distribution or automated fulfilment, see distribution centre solar and fulfilment centre solar. When you are ready, request a quote from your meter data, see the cost guide or read the cold storage solar FAQs first.