Mitsubishi Heavy Industries, Ltd. (MHI) has developed a truck refrigeration unit that enables simultaneous temperature control of two separate cargo compartments with different temperature settings entirely by heat pump. The unit marks the world's first application of a heat pump for a truck refrigeration unit, according to the manufacturer.
The heat pump enables effective transfer of thermal energy from the compartment needing a lower temperature to a cargo room requiring higher temperature, providing more than double warming capacity compared with conventional systems that use heat from a compressor, according a company statement.
The needs for a truck refrigeration unit that enables warming, chilling and freezing management in different temperature ranges within one truck has been increasing in the distribution industry in order to boost delivery efficiency in a quest to reduce energy consumption and CO2 emissions, MHI says. When chilled products and warm foods, such as rice and bread products, are carried in different compartments, the new unit can meet industry needs by accommodating seasonal ambient temperature changes flexibly and providing optimal operations: for example, cooling of both compartments in summer, heating of both in winter, and simultaneous heating and cooling in spring and autumn.
Dubbed the TDJS35HP series, the new refrigeration unit can maintain a 41 degrees F cold temperature in the front compartment and a 68 degrees F warm temperature in the rear compartment — a temperature suitable for warm rice-based foods and bread — with an ambient temperature range between minus 50 and 104 degrees F. Rated heating capacity is 5.7 kilowatts (kW).
The pre-existing TDJ301DM series, featuring 2.5 kW rated heating capacity, uses hot-gas bypass technology. Compared with the TDJ301DM, the new model achieves a 130% increase in heating capacity and 35% improvement in energy consumption, and as a result overall it realizes 3.5 times greater efficiency and 70% lower energy consumption, according to the manufacturer.
At maximum, the unit will enable a reduction in energy consumption by 75% compared with conventional systems; it will also realize significant energy savings and reduced CO2 emissions, MHI says. The company will launch sales of the new unit in April 2012, initially targeting installation in food transport trucks that require different temperature settings.
MHI and Ryoju Cold Chain Co., Ltd. will exhibit the new truck refrigeration unit at the 2011 Tokyo Truck Show from October 27 through 29. Ryoju Cold Chain is a wholly owned subsidiary of MHI, which handles domestic marketing of truck refrigeration units. Going forward, on the strength of the new model's outstanding energy-saving features, MHI said, it intends to aggressively develop the market for variable-temperature product distribution.