Cold storage myths, debunked

Cold storage is a technical, high-stakes purchase, and the internet is full of half-truths that lead buyers to under-specify, choose the wrong refrigerant, or write off measures that would genuinely cut their bill. Here are the five we hear most, with the honest position on each.

Myth 1: "Any refrigeration engineer can size a cold store"

Fixing a fridge and designing a cold store are different disciplines. A cold store is sized on refrigeration duty — the kilowatts of cooling needed — which is the sum of product pull-down and holding heat, ingress through the insulated envelope, air infiltration through doors and docks, fan and lighting gains, defrost energy, and any process load such as blast freezing. Get that calculation wrong and you either buy plant that cannot hold temperature on a hot day or, just as costly, oversize it and pay for capacity you never use. Sizing also drives the refrigerant choice, the number of compressors for N+1 redundancy, and the panel spec. A general engineer who sizes on floor area rather than duty is guessing. Proper design pulls your half-hourly meter data and throughput first — the same discipline that separates a store that runs reliably for a decade from one that becomes a running-cost and audit problem. See how the economics follow from getting the duty right.

Myth 2: "CO2 and natural-refrigerant plant is unreliable"

This one is a decade out of date. CO2 (R744) transcritical plant is now mainstream across UK supermarket depots and industrial cold stores, and it is not only reliable — it is more efficient, with energy savings of around 19 per cent demonstrated against legacy R404A. Low-charge ammonia (R717) has been the workhorse of the largest industrial refrigeration for generations. The real reliability risk runs the other way: staying on high-GWP HFCs such as R404A and R410A, which are being squeezed hard by the GB F-gas quota (an ~80 per cent HFC cut by 2036) and are becoming scarcer and more expensive to service. A natural refrigerant is the resilient, future-proof choice, not the risky one. R410A is already not permitted in most new equipment from 2025.

Myth 3: "Solar can't help a 24/7 refrigeration load"

The opposite is true — cold storage is one of the best matches for on-site solar there is. The usual weakness of commercial solar is that generation peaks in the day while load is uneven, so a lot of the energy is exported cheaply. A cold store does not have that problem: the refrigeration load runs around the clock, so self-consumption is unusually high and almost every generated unit displaces a unit you would otherwise buy at full retail price. Solar does not replace efficient plant, and for a constant load the export earned under the Smart Export Guarantee is minor because you use nearly all of it yourself — but it directly reduces the biggest cost on site. We frame solar strictly as a running-cost offset; the array itself is sized by our sister service for solar for cold storage against your real half-hourly load.

Myth 4: "The cheapest panel is fine — insulation is insulation"

Insulation is where a false economy does the most lasting damage. The cold-store envelope is the barrier between your controlled temperature and the ambient outside, and heat ingress through an under-specified panel is a cost you pay every hour for the life of the building. Chilled rooms typically need 80 to 120mm PIR insulated panel; frozen rooms 120 to 200mm, with vapour-sealed joints and a frost-heave-protected floor on freezers. Skimping on thickness or, worse, on the sealing of the joints and vapour barrier, means the plant works harder continuously — and on a freezer, poor floor detailing can cause frost heave that physically damages the structure. The panel is not the place to save money; the door discipline, strip curtains and rapid-action doors are where the cheap wins are.

Myth 5: "A cold store is just a big fridge — monitoring is optional"

For any food-grade store, monitoring is not optional; it is the audit. BRCGS, SALSA and customer audits require documented, mapped and alarmed temperature control, and HACCP-critical steps such as blast-freeze pull-down must be validated with recorded times and core temperatures. A store commissioned without validated temperature mapping, calibrated probes and alarms may hold temperature perfectly and still fail an audit because it cannot prove it. Monitoring is also your early-warning system: it is what tells you a plant fault is developing before it becomes spoiled stock. Every store we build is commissioned audit-ready, with mapping and alarms set up from handover.

The through-line

Every one of these myths points the same way: cold storage rewards doing the engineering properly and punishes shortcuts, because the running cost and the audit risk run for the whole life of the building. Size on duty, build the envelope tight, choose a refrigerant with a future, and prove the temperature — and the store earns its keep. Guess, skimp or cling to a dying refrigerant, and it costs you every year.