In its latest hefty tome, Climate Change 2013: the Physical Science Basis, the IPCC lists the new HFO R1234yf as having a 20-year GWP of 1 and a 100-year GWP of less than 1. Its sister refrigerant R1234ze(E) is listed as having a 20-year GWP of 4 but, like yf, a 100-year GWP of less than 1.
Welcoming the report, Ken Gayer, vice president and general manager of Honeywell Fluorine Products, said “Automakers around the world are choosing HFO-1234yf not only for its environmental attributes, but because it is easy to adopt, is safe, and it performs well in all climates,”
The IPCC report suggests that the influential body, which advises governments around the world on the science of global warming, has accepted the findings of an independent, peer-reviewed paper, published last year in Reviews of Geophysics by several leading chemists and environmental scientists from Europe and the US. That study was the first to calculate the GWPs of all fluorocarbon-based refrigerants using all available atmospheric data, taking into account local atmospheric patterns. It found R1234yf to have a GWP of less than 1. CO2 is considered the baseline with a GWP equal to 1. Earlier studies had calculated the GWP for R1234yf at 4.