A sorption-based thermochemical storage and cooling system for cold chain transportation driven by engine waste heat.

The drastically increased demand for temperature-controlled environments for food/medical storage and transportation calls for more efficient and environment friendly cooling systems to reduce their effect on climate change. Commonly used cold chain transportation vehicles have an overall thermal efficiency of ~35%, implying that ~65% of energy input is rejected to the ambient as waste heat. Over the rejected waste heat, ~54% is through the exhaust gases (~400-500 degC) and ~46% though the water coolant circulation (~80-90 degC). In this work, we use the waste heat to drive a newly developed sorption based thermochemical energy storage and cooling system. Such a system uses the air and an absorbent as a working pair, and energy storage and cooling are released through air dehumidification using the desiccant material and evaporative cooling. A schematic diagram of the proposed energy storage and cooling system is shown in Fig. 1 with a brief description. The absorbent is regenerated using the rejected heat through either or both of the water coolant or the engine exhaust. The newly proposed storage and cooling system has the potential to improve the vehicle thermal efficiency and reduce CO2 and particulate emissions. It also provides an alternative to the vapor compression based refrigeration cycles with an eco-friendly system.