Conservation and Efficiency - Energy Policy Analysis: A Conceptual Framework - page 172

The National Highway Traffic Safety Administration (NHTSA) introduced new CAFE standards
for model year 2011 light-duty vehicles in 2009, and in 2010 NHTSA and the U.S. Environmental
Protection Agency jointly announced CAFE and greenhouse gas emissions standards for model
years 2012 to 2016. Light-duty vehicles are required to reach an average fuel economy of 35 mpg
by model year 2020 (USEIA 2011b).
Market adoption of advanced technologies in conventional vehicles is expected to improve
fuel economy through model year 2020 and reduce fuel costs thereafter, due in part to greater
penetration of unconventionally fueled (electric, hybrid, natural gas, hydrogen) vehicles and
in part to the addition of new technologies in conventional vehicles. These advanced tech-
nologies include advanced drag reduction, which provides fuel economy improvements by
reducing vehicle air resistance at higher speeds; adoption of lightweight materials through
material substitution; advanced transmission technologies, including aggressive shift logic,
continuously variable, automated manual, and six-speed transmissions; cylinder deactivation
and turbocharging; and electrification of accessories such as pumps and power steering (USEIA
2011b). It is both technically feasible and cost-effective to raise the average fuel economy of
new passenger cars and light trucks even if gas drops back to $2.50 a gallon. Using continuously
evolving conventional technologies, automakers could produce a fleet of cars and light trucks
that achieve over 35 mpg by 2020. Hybrid, fuel cell, and other advanced technologies could be
used to make vehicles even more efficient while maintaining, if not improving, vehicle safety
and performance (UCS 2007).
RESIDENTIAL SECTOR
The residential sector includes all private residences, including single-family homes, apartments,
manufactured homes, and condominiums, accounting for about 23 percent of total U.S. energy
consumption in 2010 (USEIA 2011a, 38). Energy use in this sector varies significantly across
the country, due to regional climate differences and different regulations. On average, about 60
percent of the energy used in U.S. homes is expended on space conditioning (heating and cool-
ing) (USEIA 2011b, 34).
How energy is used in American homes has changed substantially over the past three
decades. U.S. homes on average have become larger, have fewer occupants, and are more
energy-efficient, due in part to building code and appliance standards with strict efficiency
requirements. In 2005 energy use per household was 95 million British thermal units (Btu) of
energy compared with 138 million Btu per household in 1978, a drop of 31 percent. In 2009, 58
percent of housing units had energy-efficient, multipane windows, up from 36 percent in 1993.
Multipane windows are much more prevalent in newer homes. About 80 percent of houses built
since 2000 have double- or triple-pane energy-efficient windows, up from only 52 percent of
homes constructed before 1990. Over 40 million householders have used caulking or weather-
stripping to seal cracks and air leakages around their home, 26 million have added insulation,
and 68 million have at least some energy-efficient compact fluorescent (CFL) or light-emitting
diode (LED) lights. Appliances (refrigerators, freezers, ovens, stoves, dishwashers, clothes
washers, and clothes dryers), heating, and cooling equipment now use less energy. In addition,
less heat passes through the walls, roofs, and windows of homes because of better insulation
and construction. At the same time, however, many homes contain more energy-consuming
devices. The type and number of home electronics have increased significantly over the past
thirty years (USEIA 2011b).