Of all the things you might be expecting on the front line of geopolitical conflict, the supermarket chiller cabinet is not an obvious contender. But since October, waves of cyberattacks across Europe have exposed the vulnerability of humble refrigeration systems and our dependency on them.

Yes, this goes far beyond attacking the frozen peas in aisle seven. From Sweden, where supermarket refrigeration controllers were set to 50C, to France where blood-storage facilities were targeted alongside food retailers, cybersecurity researcher Fredrik Blix has estimated that around 940 shops across Europe have been affected.

On a Feltham industrial estate, staff at Langridge Organics are winding down after another hectic morning of deliveries to customers, including Planet Organic.

Owner Alex Pearce started the business with his uncle in 1985 and is remarkably well hedged against emergencies, with solar panels, 48 batteries capable of running the business for 15 hours and enough renewable diesel for eight weeks of deliveries.

The only thing they hadn’t thought of was a cyberattack on their fridges. On November 2, Pearce arrived just after 5am to find defrost lights blinking. One controller displayed “150 degrees”, although the fridge itself was at 6.2C. Another unit was also defrosting. “So now I’m thinking, this is not right because these two fridges are not connected.”

Then another light came on. Six of his 10 refrigeration controllers had altered settings, including a defrost cycle set to 50 degrees. Pearce disconnected the central monitoring system.

Fourteen hours later, an email arrived from the National Cyber Security Centre warning that the business had been hacked. “I’d already figured that out,” he says.

Of course we’d all like to know who is behind this. Two pro-Russian groups claimed responsibility for the European attacks. But French officials have since accused hackers linked to Iran’s Revolutionary Guard of orchestrating the earlier French supermarket attacks.

Meanwhile, the possibility of foreign actors targeting our food supply naturally makes us feel vulnerable, especially perhaps in London. Professor Tim Lang’s 2025 Just In Case review of food preparedness warned about the vulnerability of refrigeration operating systems.

A senior logistics insider interviewed for the report described Britain’s cold-storage buildings as typically 30 to 40 years old and often run-down. Now transpose this to London’s largely invisible food network: New Covent Garden Market, Smithfield’s meat trade and New Spitalfields, with its cold rooms and specialist ripening facilities. The whole shebang depends on refrigeration.

From mid-October cybersecurity researchers were watching. At Lupovis, CEO Dr Xavier Bellekens and his team recorded 256 attempted attacks from 91 sources over 10 days, using fake refrigeration controllers called “honeypots” to lure attacks.

Attackers exploited old vulnerabilities. But what interested Bellekens was what happened next. “They put the fridges into infinite defrost cycles.”

Professor Judith Evans, a refrigeration expert at London South Bank University, explains that defrosting is routine. Ice accumulates on the evaporator and must periodically be removed. Hackers can manipulate the settings, preventing refrigeration from restarting.

Why not simply take these fridges offline? Evans points out that supermarkets depend on connected monitoring to detect faults and dispatch engineers. Disconnecting everything would be like swapping your smartphone for a landline. Only worse.

Online I examine a controller apparently removed from a French supermarket. It is an ordinary small plastic box with a digital display you might expect controls heating in a village hall. It seems incredible it could be an instrument of geopolitical disruption.

Bob Long, founder of Lancashire-based Organic Heat Exchangers, has invented the EnergiVault thermal battery, already used at a Dundee vertical farm to regulate temperature.

He is also in talks with data centres. He sees a fault line not just with cyberattacks but the way we approach conventional cold-chain infrastructure.

Conventional refrigeration can take time to recover after a failure. “In that 10, 15 minutes, you can lose temperature control and not recover for five or six hours,” says Long.

That’s too long for many perishable goods and data centres. If we can’t keep cyberattacks at bay and cold storage offline, can we at least make it quicker to reboot, and able to run on renewables?

EnergiVault stores cooling (not electricity) in tiny ice crystals suspended in water, releasing it rapidly when needed. Long’s “thermal battery” can store one megawatt-hour of cooling energy. Long likes to explain the principle with a gin and tonic. Drop an ice cube into your drink and you have what he calls “packaged cooling”: the ice absorbs heat as it melts. EnergiVault applies the same principle on an industrial scale.

There are potentially enormous gains for the electricity grid, too. Long has his eye on places like New Covent Garden Market, where fresh produce could be kept cool using energy captured when the wind is blowing and electricity is plentiful.

There’s no doubt these recent attacks have exposed an uncomfortable truth: London’s food supply depends on refrigeration systems that can be disrupted from thousands of miles away. Keeping hackers out matters.

But the next challenge is making sure that, even when they get in, they cannot bring the cold chain to its knees.