An Introduction to the Current Cold Chain
What is the cold chain? For most people it is an unseen, seamless movement of produce to allow refrigerated goods to reach consumers. It requires a complex sequence of production, storage and distribution activities with interacting equipment and logistics combining to make this possible.
To keep things cold, energy is needed. Throughout the stages of the cold chain, energy is provided in a variety of ways. Typically, at the start of the process the grid is used to power cold storage where produce arrives from the farm or food processing plants.
Transport refrigeration is the link in the cold chain that allows produce to remain frozen or chilled while being moved. During this distribution phase, produce is taken from a cold storage depot and loaded onto vehicles to be taken to stores.
The cold chain – from producer to consumer (Image: Sunswap)
The vehicles used in transport refrigeration consist of trailers, rigid bodied trucks and vans. They all have a refrigerated compartment which is powered by a secondary diesel engine or by the main vehicle engine. In either of these cases the combustion of diesel is needed - to run the engine - to drive the compressor - to deliver cooling.
Trailers with diesel-powered transport refrigeration units (TRUs) mounted on the front. Stains from diesel fumes can be seen on the trailer roofs. (Image: KTZE)
There are an estimated 5.6m of these vehicles known as transport refrigeration units (TRUs) in the world, with around 150k in the UK. This leads to huge environmental impact, with our analysis suggesting that one TRU’s emissions are equivalent to approximately 50 Euro VI car emissions. To put this into perspective, the global TRU fleet emissions will equal that of the entire number of registered vehicles in the USA – around 280 million vehicles. This is leading to a detrimental effect on air quality and CO2 emissions, particularly in cities. And as the population increases across the world, the cold chain will expand, and more diesel power is required. This is reflected by the unprecedented growth seen in the UK cold chain, which was valued at £3.5bn in 2018 and is projected to reach £18.8bn billion by 2026 [Allied Market Research].
Clearly there are problems with the status quo, but what is the alternative? The automotive sector has seen a huge shift to electric, zero emission technology. Driven in part by UK government policy stating that the sale of conventional cars and vans will cease by 2040, with an expectation for 50-70% of all new cars being Ultra Low Emission Vehicles by 2030.
Making TRUs electric has challenges, particularly with cost and grid capacity when charging at a fleet level. But with the growing grid infrastructure and charging networks, and cost of lithium batteries being reduced by 87% in the last 10 years [BNEF], the cold chain can take a lead from the automotive sector.
In the next few years, as there is a greater focus on environmental issues and an appetite to change from fleet operators, facilitated by government intervention and following the example set in the automotive industry, the future could look very different with a cold chain which is free of carbon.
Co-founder & COO at Sunswap