Danfoss introduces CO2 Adaptive Liquid Management (CALM) and improves CO2 efficiency by as much as 10%

Thursday, December 5, 2019

The Danfoss CO2 Adaptive Liquid Management fully utilizes all of an evaporator's surface area, improving the energy efficiency of transcritical CO2 refrigeration systems by as much as a 10%. CALM achieves these great savings by combining Danfoss' Liquid Ejector with the Adaptive Liquid Control (ALC) case controller algorithm and Danfoss ADAP-KOOL® system controls.


CALM is a complete solution, with an intelligent system manager, smart pack, and case controllers, featuring two groundbreaking Danfoss innovations: the ALC case controller algorithm and the Liquid Ejector. The Liquid Ejector uses expansion energy from the gas cooler to efficiently remove liquid from the suction side. The ALC case controller algorithm then safely injects more refrigerant into the evaporator, increasing evaporation temperature and controlling superheat to close to zero. Together, these components optimize evaporator performance, increase suction pressure, and decrease compressor energy consumption in display cases and cold rooms.

Increasing the evaporating temperature increases suction pressure, which in turn reduces both the load on the compressor and energy consumption. In fact, the ALC algorithm can typically achieve energy savings of 5% better than minimum competitive active superheat management systems and 10% better than fixed superheat solutions.

Thousands of CO2 refrigeration installations prove that Danfoss components are already helping customers make the transition to low-GWP refrigerants while saving energy, maintaining system reliability, and ensuring food safety. With CALM, Danfoss offers a cutting-edge CO2 solution for all climate zones and store sizes, helping food retailers all over the world transition to CO2 as a refrigerant.