KIMM opens new era of eco-friendly refrigerants by developing an inexpensive refrigeration system that uses water

• KIMM develops a 350-kW vapor compression refrigeration system that utilizes water, which has an environmental pollution index of “zero” and is cheaper than conventional refrigerants by up to 100 times, as a refrigerant
• As the government aims to reduce the usage of some refrigerants by 80 percent before 2045, “water” will likely replace other eco-friendly refrigerants
  

International regulations on refrigerants are becoming increasingly stronger to achieve carbon neutrality. In this context, the Korea Institute of Machinery and Materials (President Seog-Hyeon Ryu, hereinafter referred to as KIMM), an institute under the jurisdiction of the Ministry of Science and ICT, has developed a cooling technology that utilizes water with an environmental pollution index of “zero” as a refrigerant* for the first time in the country. This innovative technology is economically efficient as it is cheaper to use compared with existing technologies that rely on chemical refrigerants. The newly developed technology will likely contribute to the realization of carbon neutrality by allowing eco-friendly refrigerants to be applied to air conditioners and industrial chiller/heat pump systems in the future.

*Refrigerant: A refrigerant is a chemical used for lowering the temperature within a system by absorbing the heat through a circulation process.

• Senior Researcher Jungchul Kim, Heat Pump Research Center of KIMM, has succeeded in developing, for the first time in the country, the core technology for producing an environment-friendly refrigeration system capable of cooling or transporting heat by using water as a refrigerant.
• The newly developed system, which uses water as a refrigerant in lieu of chemicals, is eco-friendly and inexpensive. Hence, it is expected to not only reduce the costs required for procuring refrigerants but also significantly enhance the efficiency of system maintenance and operation. Previously, this technology was developed only in advanced nations such as Germany and Japan, and the KIMM has managed to secure a competitive edge in this sector by successfully developing the core technology for the first time in Korea.
  
• The KIMM has developed a centrifugal compressor that uses water as the refrigerant, unlike conventional compressors that utilize synthetic refrigerants, as well as an evaporator and a condenser. This system is designed to suit the unique characteristics of water, which is generally difficult to compress, and is capable of optimizing the advantageous features of water throughout the cooling process while at the same time maintaining functionality parallel to that of conventional systems. Korea Institute of Industrial Technology(KITECH) and Jinsol Turbo Machinery participated in the development of the system.
  
• Environment-friendly refrigerants such as ammonia and propane are often flammable or toxic. Therefore, under the High-pressure Gas Safety Control Act, separate safety devices must be installed within the refrigeration system when using these refrigerants. On the other hand, systems that use water as a refrigerant have the advantage of not requiring separate safety equipment, as water is non-toxic and non-flammable.
  
• Due to stronger environmental regulations, refrigerants that are currently being used in the market must either be disposed of or reduced by up to 80 percent depending on the type of refrigerant by 2045. Meanwhile, the problems associated with eco-friendly synthetic refrigerants that are being sold for development purposes are that they are relatively expensive and that the market is monopolized by corporations specializing in the production of these refrigerants. Therefore, there is a pressing need for an alternative to conventional refrigerants.
  
• One of the major advantages of the cooling system newly developed by the KIMM is that it can save system maintenance costs as it uses water as a refrigerant, which costs up to 100 times less than conventional refrigerants. Moreover, by using water as a refrigerant, heat can be absorbed and released in a more efficient manner, thereby producing the same cooling effect as conventional refrigerants while reducing energy consumption and electricity expenses.
  
• Senior Researcher Jeong-Cheol Kim of the KIMM remarked, “For the first time in Korea, we have developed an industrial chiller and heat pump system that uses water as a refrigerant, which used to be developed mainly in a small number of advanced countries.” Senior Researcher Kim added, “Following the introduction of stronger regulations on refrigerants, there is a growing demand for the development of environment-friendly chiller and heat pump technologies. We will make all-out efforts so that these technologies can be systematically developed and commercialized within the country.”
  
• Meanwhile, this research was conducted with the support of the project for the “development of a 350-kW compression-type cooling technology using natural refrigerants (R-718),” a project subsidized by the Ministry of Trade, Industry and Energy.
  

President Seog-Hyeon Ryu of the KIMM remarked, “This research is substantially meaningful in that the KIMM has successfully commercialized its technology jointly with a research institute spin-off company established through the KIMM’s investment of its original patented technology.” President Ryu also said, “We will continue to devote ourselves to the development of technologies that can contribute to the development of national strategic technologies and also to the revitalization of local economies.”