TRANSPORT REFRIGERATION RECENT DEVELOPMENTS TO REDUCE EMISSIONS AND ENERGY CONSUMPTION
Transport refrigeration in the EU has already implemented measures to reduce refrigerant emissions, through the use of R-513A and R-452A as lower GWP replacements for R-134a and R-404A. Companies are working to adopt refrigerants with GWPs considerably lower than R-452A. Electric drive compressors, for last mile delivery, hermetic module systems for refrigerated trailers and improved control systems to reduce energy consumption are improving environmental performance. As truck manufacturers and suppliers begin to move toward electric-powered vehicles and components, the same trend is emerging for trailer refrigeration. The benefit of transport refrigeration is emphasised by the food losses that occur in its absence. A recent article states that new partnerships, technologies, government efforts and better cold chain infrastructure, temperature-controlled supply chains are being implemented in Africa to address losses due lack of refrigeration and other related factors Annual food losses for fruits and vegetables are an estimated 40 to 50 percent.
A Swedish company offers a new electric integrated lightweight compact cooling system uses HFC-134a designed for small commercial vehicles with tight engine compartments used for last mile deliveries. The compact compressor/condenser unit fits in the spare wheel compartment underneath the vehicle, while the evaporator is fitted to the ceiling of the cargo compartment. The innovative variable speed inverter compressor with smart derating function saves energy prevents excessive battery discharging, ensures reliable cooling and prolongs service life. Stationary cooling can be used to boost efficiency and save vehicle battery power by connecting the vehicle cooling system to a mains socket a few hours before delivery to provide a pre-cooled cargo compartment.
Source and manufacturer’s information
A new generation design of refrigeration systems for trailers uses hermetic modules to maximise reliability. The refrigerant used is R-452A a non-flammable HFC/HFO blend with a GWP of 2140 (compared to 3922 for R-404A). Conventional trailer cooling units have a central refrigeration circuit. The new system has three identical ‘plug & play’ refrigeration modules that are less susceptible to faults with each module having a separate, hermetically sealed refrigerant circuit. The hermetic cooling modules can be exchanged in the event of failure which would not require a certified refrigeration technician. The modules are upgradable to meet future refrigerant requirements, such as legal standards. Instead of investing in an entirely new system, it should be possible in the future to use modules with an appropriate refrigerant.
Source and manufacturer’s information
Reducing energy consumption has been a major focus for reefer manufacturers for many years, but now there is an increased focus on reefer energy consumption, in part due to the increased cost of low sulphur fuel for shipping lines. Energy consumption reduction means a reduction in fuel consumption which means a cost reduction in general. Power management control software and systems can reduce energy consumption by over 50%. Intelligent cycling of the refrigeration unit compressor and fans provides energy savings in the range from 10% to 65%, dependent on the commodity carried and the refrigeration unit model.
Electric trailer refrigeration source Reefer energy saving source
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