Buildings consume approximately 40 percent of the energy and 70 percent of the electricity in the United States annually. Proper building "siting" - determining where a building sits, how it faces the sun, window placement and light design - will impact electric lighting and gas or oil-based heating needs. Proper insulation can reduce the use of oil or gas by ensuring that windows, doors and walls aren’t leaking heated or cooled air. Provisions in the Energy Bill relating to buildings could bring reductions in CO2 emissions of up to 647 million tons per year by 2030, equivalent to the annual emissions from 162 coal burning power plants.