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Development of Technology and Assessment Techniques for Next-Generation Refrigerants with a Low GWP Value

Project overview

Project period: FY2018 to FY2022, FY2022 budget: JPY 550 million
PL: HIHARA Eiji (Professor, Graduate School of Frontier Sciences, University of Tokyo)
SPL: SAITO Kiyoshi (Director, Interdisciplinary Institute for Thermal Energy Conversion Engineering and Mathematics, Organization for University Research Initiatives, Waseda University)

For refrigerants used in refrigeration and air conditioning equipment, there is an ongoing shift from specified fluorocarbons*1 (i.e. CFCs*2 and HCFCs*3 that destroy the ozone layer) to alternative fluorocarbons*4 known as HFCs*5, but there is a problem in that HFCs have high greenhouse impacts. Therefore, given the increase in HFC emissions resulting from the above shift, international HFC regulations are currently being tightened. In particular, the 2016 amendment to the Montreal Protocol*6 mandates the phased reduction of HFC production and consumption. As a result, developed countries must reduce their use of HFCs by 85% compared to the base year by 2036, and there is an urgent need to convert to refrigerants that have much lower greenhouse impacts.

At the same time, technologically speaking, it is extremely difficult for many green and other next-generation refrigerants—which have extremely low global warming impacts--to realize equipment performance rivaling that of conventional HFC refrigerants. Such refrigerants also have safety issues (e.g., flammability, chemical instability), so it has not yet been possible to globally achieve the practical application of refrigeration and air conditioning equipment that uses next-generation refrigerants. One major cause of this is that no standard methods have been established for evaluations of the basic characteristics of next-generation refrigerants or for safety evaluations and risk assessments performed when using such refrigerants. Furthermore, in the refrigeration and air conditioning equipment field, although next-generation refrigerants have been applied in some cases, technical issues have prevented their widespread diffusion.

The goal of this project is to set up a development infrastructure for green and other next-generation refrigerants as well as for energy-saving refrigeration and air conditioning equipment that use such refrigerants. Therefore, this project involves implementing research and development aimed at establishing safety and risk assessment methods for next-generation refrigerants used for commercial freezing/refrigeration equipment as well as for small and medium-scale refrigeration/air conditioning equipment, including household air conditioning equipment in particular. This project also aims to achieve the practical application and diffusion of next-generation refrigerants and refrigeration/air conditioning equipment that use such refrigerants by developing new technology and resolving technical issues hindering their diffusion.

  • *1 Freon (or fluorocarbons)

    Freon is a brand name for various refrigerants. It is also used as a generic name for fluoride-based refrigerants and industrial gases.

  • *2 CFCs

    An abbreviation for chlorofluorocarbons. An artificial compound resulting from the replacement of all the hydrogen in low-molecular-weight organic matter with fluorine/chlorine. A type of fluorocarbon.

  • *3 HCFCs

    An abbreviation for hydrochlorofluorocarbons. An artificial compound resulting from the replacement of some of the hydrogen in low-molecular-weight organic matter with fluorine/chlorine. A type of fluorocarbon.

  • *4 Alternative fluorocarbons

    HFCs (hydrofluorocarbons) and other compounds that do not contain chlorine, which causes destruction of the ozone layer.

  • *5 HFCs

    An abbreviation for hydrofluorocarbons. Although HFCs do not destroy the ozone layer, they are potent greenhouse gases, and the Paris Agreement calls for reduced HFC emissions.

  • *6 2016 amendment to the Montreal Protocol

    Adopted as a result of the 28th Meeting of the Parties to the Montreal Protocol (MOP28) held in Kigali, Rwanda, in October 2016. Also called the Kigali Amendment.

Basic information

Technical field
  • Fluorocarbon countermeasures
Project code P18005
Department in charge
  • Environment Department (TEL: +81-44-520-5248)

Last Updated : April 13, 2022