Cooling emissions and policy Synthesis report: Benefits of cooling efficiency and the Kigali Amendment

As we face the growing climate emergency, where the world is starting to warm itself with self-reinforcing feedbacks, and tipping points are fast approaching, it is instructive to look to the Montreal Protocol on Substances that Deplete the Ozone Layer for guidance and inspiration. The Montreal Protocol is widely acknowledged as the world’s most successful environmental treaty. It solved the first great threat to the global atmosphere from chlorofluorocarbons and other fluorinated gases that were destroying the protective stratospheric ozone shield. At the same time, the Protocol has done more to reduce the climate threat than any other agreement. This is because fluorinated gases are powerful greenhousegases, as well as ozone depleting substances. The Montreal Protocol and preceding efforts to eliminate CFCs have avoided an amount of warming that otherwise would have equaled the contribution from carbon dioxide (Velders et al. 2007).It is astounding that a single treaty has done this double duty so brilliantly. There are many lessons to be learned, including that the Montreal Protocol has always been a “start and strengthen” treaty: it started with mandatory control measures to cut fluorinated gases on a precise schedule, learned on-the-job by striving to meet the controls, and gained confidence from its initial success to do still more for the environment. The Montreal Protocol’s latest control measure is the 2016 Kigali Amendment to phase down hydrofluorocarbons, or HFCs, primarily used as refrigerants. While HFCs do not affect the ozone layer, they are potent greenhouse gases and phasing them down has the potential to avoid up to0.5°C of warming by the end of the century. The initial phasedown schedule of the Kigali Amendment ensures about 90% of this will be captured. Just minutes after the Kigali Amendment was agreed, the Parties to the Montreal Protocol passed the first of a series of decisions to improve the energy efficiency of cooling equipment in parallel with the switch from HFCs to climate-friendly refrigerants. Improving the efficiency of cooling equipment has the potential to more thandouble the climate benefits of the Kigali Amendment, with the combined potential to avoid the equivalent of up to 260 billion tons of carbon dioxide by 2050. This will save nearly $3 trillion dollars in energy generation and transmission costs, in addition to reducing consumers monthly electricity bills, while also protecting public health and agricultural productivity by reducing air pollution. This synthesis report analyzes these and other benefits, and provides more detailed support in an accompanying assessment (Dreyfus et al. 2020). We should all draw courage from the success of the Montreal Protocol and the parallel efforts to improve energy efficiency of cooling equipment, which together represent one of the most significant climate change mitigation strategies available.