IIT Madras Develops Green Supermarket Refrigeration System


CO2 traps heat in the atmosphere, contributing to climate change and also leads to many respiratory diseases and with this system this issue can be solved to an extent

IIT Madras is all set to launch India’s first green supermarket refrigeration system, with all these advantages, the transcritical system is still not perfected yet. But might be closer to transcritical refrigeration.

Transcritical refrigeration

Researchers from the Department of Mechanical Engineering in the Indian Institute of Technology (IIT), Madras presented India’s first CO2 transcritical system at the Gustav Lorentzen conference in Valencia last week.

It’s a multi-faceted system with all the modes of operation, including supermarket, air conditioning and heat recovery according to the IIT Madras faculty. This is the first of its kind in India, and it’s operating successfully in very high ambient temperatures of up to 45°C.


The researchers have improved the system by adding a liquid ejector and flooding the evaporator in the system. This resulted in an improvement of the CO2 cooling stability and an overall reduction in power.

This ultimately could result in applications such as mass cooling, like in supermarkets and cold boxes, typically used in catering and medical storage fields with a green value to it. If the system is found to be operating properly and maintenance is free, then the system could benefit the Indian markets.

CO2 as a refrigerant

Transcritical CO2 systems were developed in the early 2000s. This system puts CO2 in a transcritical cycle, meaning CO2 is made to undergo different phases with varying pressures and temperatures.

One of the main advantages of the transcritical system is that CO2 is abundantly available in the environment, which it uses plentiful. Waste produced CO2 can also be used in this system reducing the overall greenhouse gases in the environment.