Studies Done on Refrigerant Gas

The active threat of global warming and the Kyoto Protocol are driving the push for green technologies, including the quest for alternative refrigerant sources. Since the 1990s, according to one Japanese study, "refrigerant gases used in air conditioning equipment--CFCs and HCFCs--have been replaced by hydrofluorocarbons (HFCs). But HFCs are designated a greenhouse gas under the Kyoto Protocol and have a high global warming potential (GWP)." This study, and two others, demonstrate recent scientific work in this area.

Japan: Modeling the Effects Over Time of R-1234-YF

• A Japanese study presented in 2010 in Tokyo created a model to estimate the environmental concentrations of a next-generation refrigerant in Japan and its decomposed products over time with an atmospheric dispersion model. Scientists studied R-1234-YF, using estimates of three types of air-conditioning units--home, institutional and auto--and extrapolated the effects in Japan from 2011 through 2047. The study concluded: "The health effects caused by the direct inhalational exposure of R-1234YF in atmosphere can be ignored. Since the increases in O3 and HCHO, as compared to the control case, were estimated to be approximately 0.005 percent and 0.02 percent, respectively, for the spatially averaged concentrations, the effects of R-1234YF on oxidant formation in the troposphere in Japan appears to be very small."

  Hideo Kajihara, Kazuya Inoue, Kikuo Yoshida, Ryuichi Nagaosa

  Research Institute of Science for Safety and Sustainability (RISS)

  National Institute of Advanced Industrial Science and Technology (AIST)

  16-1 Onogawa, Tsukuba 305-8569, Japan

  beyondhfcs.org/files/studies/aist-hfo.pdf

Panasonic: Application of Low GWP Potential Refrigerants for Room Air Conditioners

• A study by Panasonic presented in 2010 analyzed the performance of various types of "low GWP" or low Global Warming Potential refrigerants, the so-called "new generation" of refrigerants. Several were tested: R-410A; HFO-12234yf; R-32 and 1234yf mixtures at 20/80 percent and 50/50 percent; and R-32. Scientists concluded in part that the performance of the HFO-12346f is "significantly lower than that of R-410A as a result of the pressure drop increasing. Cooling capacity of HFO-1234yf is only 70 percent of the rated capacity under maximum compressor speed."

  Akira Fujitaka, Tsutomu Shimizu, Shigehiro Sato, Yoshikazu Kawabe,

  Panasonic Corporation, Home Appliances Company

  Kusatsu, Shiga 525-8555, Japan

  beyondhfcs.org/files/studies/panasonic-hfo-tests.pdf

EPA: Exchange Refrigeration System With Steam

• The EPA commissioned George Washington University with a grant of $180,000 to investigate the potential of developing an environmentally friendly pressure exchange (PE) refrigeration system. The project period was Oct. 1, 2000 through June 30, 2005. The project tested steam-ejector technology as an alternative to the air-conditioning systems used presently in automobiles. Conclusions over this five-year long study were numerous, but one specific finding was that "PE ejector refrigeration is an excellent candidate for vehicular air conditioning using waste heat. Our research has shown that there is more than enough heat rejected from an automotive engine to provide adequate air conditioning for the vehicle."

  Exchange Refrigeration System With Steam

  Investigators: Charles A. Garris Jr.

  Institution: George Washington University

  EPA Project Officer: Mitch Lasat

  EPA Grant Number: R828563