MacArthur is joining a number of other philanthropic donors to create a new fund to help expand energy efficiency efforts in developing countries. The fund will help support government-funded work expected as the result of a Montreal Protocol amendment to phase down hydrofluorocarbons (HFCs), which are used for cooling and refrigeration. Eliminating HFCs could prevent up to 0.5 degrees celsius of global warming by the end of the century. The 19 funders have committed a total of $53 million in addition to what supporting governments have pledged. The fund will help developing countries transition to more efficient cooling equipment and phase out use of HFCs, replacing them with newer, climate-safe coolants.