How heatwaves affect cold chain storage: summary
- Heatwaves increase temperature differences, forcing cold stores to work harder
- Refrigeration systems consume more energy as external heat levels rise
- Peak electricity demand during heatwaves can increase operational risks
- Cold chain transport and storage face greater pressure in extreme heat
- Better insulation, automation and air curtains help reduce heat intrusion
Heatwaves have scorched Europe for weeks now, with temperature records being consistently broken across the continent.
Perishable goods need to be kept out of this heat to be safe for consumers to eat, but transporting and storing them is challenging, even at the best of times.
During a heatwave, those challenges become even greater. Extreme temperatures place additional strain on cold chain storage, making it harder to maintain the consistent conditions needed to preserve food quality and safety.
What is cold chain storage?
Cold chain or cool chain is the combination of technology and business practices that allows the storage and transportation of perishable goods.
This can involve a number of methods to keep temperatures low, explains Richard Russell, managing director of the UK branch of logistics company New Cold.
These include extensive refrigeration systems that remove heat from storage areas, sensors to carry out real-time monitoring, and insulated buildings to minimise the entrance of heat.
“The objective is to maintain an uninterrupted cold chain from manufacturer to retailer, ensuring food safety, product quality and shelf life,” says Russell.
How do heatwaves increase pressure on cold chains?
Heatwaves increase the difference in temperature between the inside and the outside of a cold store, Russell explains.
More heat enters the building through walls, doors, roofs and loading docks than usual, and every time a door opens, heat will enter the building, forcing the equipment to work harder.
Cold chain systems tend to use more energy than usual in a heatwave, Russell explains, as they must remove a greater amount of heat that is entering the facility in question.
This can be exacerbated by the fact that heatwaves often coincide with peak electricity demand, meaning the grid may be more unstable. As facilities are already using more energy, the instability of the grid could make things even more difficult.
All this can have a knock-on effect on how much it actually costs to store food. Higher energy use during heatwaves can lead to much steeper costs.
How can these issues be mitigated?
There are a number of ways to mitigate the worst effects of the heat.
For example, reducing the loads of products that are used can help make cold chains more resilient, one study suggests. Moving products at night, when it is cooler, also helps protect them from the heat.
Techniques from hotter regions such as Australia, the Middle East and Southern Europe are increasingly becoming relevant in Northern Europe, explains New Cold’s Russell.
Reflective roofing systems, air curtains and rapidly closing doors can help keep out heat, as can better insulation. Facilities themselves should be designed “to anticipate 35°C or even 40°C”, says Russell.
According to investment firm CBRE, much of the UK’s cold chain stock is outdated.
Automation can also help to keep heat out, reducing the amount of people that have to go in and out of a given facility, and therefore meaning doors stay closed as much as possible.
Overall, the pressure exerted on cold chain by heatwaves is very real, causing equipment to work harder and energy use to tick up. Food companies must do everything they can to mitigate this impact, and to protect food from the pressures exerted on it by heat.
