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Energy Future Fact Sheet

Science Background from the APS Energy Efficiency Report

U.S. Energy Use

  • The United States accounts for 20% of the world’s annual energy consumption, but only has 5% of the world’s population.
  • The United States holds less than 2% of the world’s known oil reserves.
  • Americans pay about $700,000 each minute to foreign countries supplying the oil from which their gasoline is produced.
  • More than half of the electricity U.S. buildings consume is generated from coal, the single largest producer of CO2 emissions among fossil fuels.

Light-duty Vehicles

  • Light-duty vehicles account for nearly half of all U.S. oil consumption and contribute about 20% of all CO2 emissions.
  • Fuel economy standards have been effective. In 1975, the first year of the federal government’s fuel economy standards for U.S. light-vehicles, the average fuel economy was 14 miles per gallon. By 1987, the fuel economy was 28 mpg for new cars and 22 mpg for new pickup trucks, minivans and SUVs.

Future Light-weight Vehicle R&D

  • Each 10% reduction in vehicle weight translates to a 6% to 7% increase in fuel economy.
  • Greater use of high-strength steel, aluminum and composite materials could improve fuel economy by reducing weight without compromising safety.
  • Thirty percent of all miles traveled are in vehicles that go fewer than 40 miles per day. If plug-in electric vehicles had batteries that could run 40 miles without being recharged, as many as 30% of vehicle-miles per day would not require any gasoline.

Energy Use in Buildings

  • Buildings account for 36% of U.S. greenhouse gas emissions related to energy use and consume 72% of the nation’s electricity.

Residential and Commercial Buildings

  • The largest "end-uses" of primary energy in residential buildings in 2005 were space heating (32%), air conditioning or space cooling (13%), water heating (13%) and lighting (12%).
  • The largest "end-uses" of primary energy in commercial buildings in 2005 were lighting (27%), space heating (15%), space cooling (14%) and water heating (7%). These four end uses account for 63% of primary energy consumption.

Reducing Residential and Commercial Energy Use

  • The energy consumption of existing residential buildings can be reduced 15% to 35% when they undergo full energy-upgrade renovations such as more efficient insulation, windows and light; elimination of infiltration and duct leakage; upgraded furnaces, boiler and air conditioners; new power supplies that waste less electricity in stand-by or low-power modes; and energy-efficient appliances.
  • Energy codes adopted in California since 1975 have resulted in energy savings of more than $30 billion, more than $2,000 per household. The energy needed to cool a new home has declined by two-thirds, to 800 kWh per year, although homes are about 50% larger than in 1975.
  • Between 1990 and 2000, appliance and automobile fuel economy standards reduced consumer energy bills by approximately $50 billion.

Building Research and Funding

  • Energy efficiency research programs have paid off. The National Academy of Science estimated in 2001 that the economic benefits from two federally funded energy efficiency R&D efforts alone were far greater than the cost of the two programs. The programs on advanced window coatings and electronic fluorescent ballasts had saved consumers $23 billion.