Sectoral report

The sectroal reports on the refrigeration energy usage in Transport can be downloaded from this page, the sectoral focus page.

• Transport

The COP (Coefficient of Performance) of transport refrigeration systems is quite low, ranging for around 0.5 at -20°C space temperature to 1.5~1.75 at + 3°C space temperature and 30°C ambient temperature. Work on refrigerated transport vehicles has shown:

• Refrigeration systems in these vehicles are invariably driven by auxiliary diesel engines.
• Average fuel consumption of articulated vehicles (excluding the refrigeration auxiliary diesel engine) is 24 l/hr. Fuel consumption of auxiliary diesel engine is approximately 2 l/hr (8% of vehicle main engine consumption).
• Capacity and size of vapour compression refrigeration systems can be reduced through the use of thermal energy storage (eutectics). For small journeys the vapour compression system can be eliminated completely.
• Sufficient reject heat is available from the engine of articulated vehicles to drive sorption refrigeration systems at normal out of town driving conditions but insufficient heat will be available in town driving. This shortcoming can be overcome through the use of an auxiliary heat source or eutectic energy storage. Other issues to be addressed are the size and mounting of the sorption refrigeration system.
• Air cycle technology is quite promising for food transport applications. Main disadvantages at present are the low COP compared to that of the vapour compression system, particularly for chilled food distribution applications, and the unavailability of off the shelf components.
• Direct power generation from the heat in the exhaust of the engine to power refrigeration systems may be a promising technology for the future. Other technologies that need further investigation and consideration are Stirling cycle powered systems, magnetic refrigeration and solar energy driven systems

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Other Aspects

CO₂ in transport

Download more information on CO₂ in transport case study