NEC and NTT develop energy-saving cooling system using greener HFO refrigerant

System is the first to use more environmentally-friendly HFO refrigerant

Japan-based NEC and NTT Communications have developed an air cooling system which they claim significantly reduces air conditioning power consumption in data centres.

The energy-saving system is the first to use a new low-pressure refrigerant called R1224yd, developed by Japanese manufacturer AGC and originally designed for centrifugal chillers, which in addition to being more energy-efficient is more environmentally friendly than other commonly used refrigerants.

Refrigerants in air cooling systems enable heat to be removed from unwanted locations and have been subject to increasing regulation due to their negative environmental effects, typically measured in Ozone Layer Depletion Potential (ODP) and Global Warming Potential (GWP).

The worst offenders are hydrofluorocarbons (HFCs) which will be phased out of cooling systems by 2025 in Europe in accordance with the EU’s 2015 F-Gas Regulation. AGC’s refrigerant is an A1 non-flammable hydrofluoroolefin (HFO) refrigerant, a new class of refrigerant with virtually-zero ODP and very low GWP.

The R1224yd refrigerant obtained ASHRAE certification in 2017 and NEC published a proof-of-concept cooling system based on the refrigerant the following year which demonstrated considerable power efficiency gains.

Based on initial tests at an NTT data centre, the companies claim their latest system’s air conditioning power consumption is half that of conventional water cooling systems. The system, which can be easily retrofitted, will go to market in 2022 and NTT plans to begin installing it in its own data centres.

“In the future, the two companies will consider providing not only communication equipment but also customers who need large-scale cooling equipment such as hospitals and commercial facilities,” the companies announced (translated).

“In addition, we plan to use the exhaust heat for a secondary use to further enhance the effect of suppressing global warming. As a result, we will be able to create new business models such as hot water that uses exhaust heat, power generation, and agriculture, aiming to be a system that contributes to society in both environmental and economic aspects.”