and on the new and updated standards adopted for a number of products since 2000, the energy savings are expected to grow to about 268 TWh (6.9 percent) in 2010 and to 394 TWh (9.1 percent) by 2020 (Nadel et al., 2006). These projections are underestimates, as they consider only the savings from standards adopted as of 2007. Federal law requires dozens of additional standards to take effect before 2020, and some states are setting standards for appliances not covered by the federal standards.

Additional appliance efficiency standards were included in the 2007 federal energy legislation. Most noteworthy are efficiency standards for general service lamps, standards that will make it illegal to sell ordinary incandescent lamps after the standards take effect. In phase one, which takes effect in three stages during 2012–2014, manufacturers will be able to produce and sell improved incandescent lamps as well as CFLs and LED lamps that meet the efficacy requirements, namely, the minimum lumens of light output per watt of power consumption. In phase two, which takes effect in 2020, only CFLs and LED lamps will qualify unless manufacturers are able to roughly triple the efficacy of incandescent lamps. It is estimated that these new standards will save 59 TWh per year by 2020, additive to the savings from standards for other products (ACEEE, 2007).

Most state and local authorities have adopted mandatory energy codes for new houses and commercial buildings, often following models such as the International Energy Conservation Code, although some state or local codes are more stringent. Building energy codes for new homes and commercial structures built during the 1990s are estimated to have reduced U.S. energy use by 0.54 quads in 2000. The DOE estimates that if all states adopted the model commercial building energy code approved in 1999 by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, owners and occupants would save about 0.8 quads over 10 years (DOE, 2007a). Building energy codes are enforced at the local level, however, and there is evidence that enforcement and compliance are weak in many jurisdictions.

The DOE spent more than $7 billion (in 1999 dollars) on energy efficiency research, development, and demonstration (RD&D) programs during 1978–2000 (NRC, 2001). The resulting efforts contributed to the evolution and commercial-