The American Council for an Energy-Efficient Economy estimates that up to February 2018 over 7 million homes have been weatherized, giving yearly savings of 2.6 TWh of electricity, 7.9 TWh (27 × 10 ^ Btu) of fossil gas and 3.2 million metric tons (3.5 million short tons) of reduced carbon dioxide emissions. The US Department of Energy estimates weatherization returns $2.69 for each dollar spent on the program, realized in energy and non-energy benefits. Families whose homes are weatherized are expected to save $358 on their first year's utility bills.