1. Residential buildings refer to single family detached and attached dwellings, buildings with 2 4 units,
and larger apartment buildings and condominium complexes, as well as mobile homes.
2. In residential buildings, improvements in energy efficiency are generally quantified in terms of energy con
sumption per household. Between 1978 and 1980 (when data were first available from the Energy Information
Administration [EIA] Residential Energy Consumption Survey), annual energy consumption per household ranged from
114 to 138 million Btu. From 1990 to 1993, this figure dropped to between 98 and 104 million Btu, and in 1997, it
stood at 101 million Btu (EIA. 2003. Annual Energy Review 2002. p. 53 table 2.5, EIA, Washington, DC. In 2001, the
most recent year of available data, annual energy consumption per household was 92 million Btu (EIA. 2004. 2001
Residential Energy Consumption Survey: Household Energy Consumption and Expenditures Tables.
http://www.eia.doe.gov/emeu/recs/recs2001/detailcetbls.html, February 4, 2005, table CE1 1c. EIA, Washington, DC.) In
commercial buildings, energy efficiency improvements are documented by examining energy consumption per square foot
of commercial building space. Between 1979 and 1983 (when data were first available from EIA's Commercial Buildings
Energy Consumption Survey), annual energy consumption per square foot ranged from 98 to 115 million Btu; between
1989 and 1992, 81 to 92 million Btu; and in 1999, (the most recent year of available data) 85.1 million Btu (EIA.
2003. op cit, p. 65, table 2.11).
3. Heavens, Alan J. 2004. Social changes affect housing market. Detroit Free Press Inc., Detroit, MI. July 2,
2004. www.freep.com, July 29, 2004.
4. Plug loads refer to electric devices that that are plugged into wall sockets.
5. R value is a measure of resistance to heat flow with units of hr F/Btu/in.
6. Low E coatings for windows reduce the flow of infrared energy from the building to the environment, effec
tively increasing the window's R value. Some of the low E coatings are also designed to reflect infrared energy from the
sun, thus reducing air conditioning loads.
7. CFCs also contribute to global warming. Thus, with the Montreal Protocol ban on CFCs, future emissions of
an important GHG were also curtailed (U.S. Climate Change Technology Program. 2003. Technology Options for the Near
and Long Term, pp. 23 24. http://www.climatetechnology.gov, February 4, 2005. National Association of Home Builders
(NAHB). 2000. Housing Facts, Figures and Trends, p. 45. NAHB, Washington, DC).
8. U.S. Census Bureau. 2004. Statistical Abstract of the United States: 2003. op cit, p. 9, table 3.
9. Nelson, A.C. 2004. The context for transportation sustainability. Presentation delivered on July 13 at the
Transportation Research Board Sustainability Workshop, http://www.trb.org/Conferences/Sustainability/Nelson.pdf,
February 4, 2005.
10. In 2001, buildings in the United States consumed 0.34 quad of wood for space heating, 0.01 quad of
geothermal energy in heat pumps, 0.05 quad of solar water heating, and less than 0.001 quad of solar photovoltaics
(Office of Energy Efficiency and Renewable Energy. 2003. 2002 Buildings Energy Databook, p. 1 11, table 1.1.4. U.S.
Department of Energy, Washington, DC.)
11. According to the U.S. Green Building Council, green products and technologies are those that offer envi
ronmental benefits (e.g., improve air and water quality), economic benefits (e.g., reduce operating costs), and health
and community benefits (e.g., enhance occupant comfort and health) http://www.usgbc.org/AboutUs/whybuildgreen.asp.
In this report, we use the terms low GHG and climate friendly synonymously to refer to those technologies and prod
ucts that result in lower greenhouse gas emissions than would the standard practice. Thus, while low GHG and climate
friendly technologies are not always green technologies and vice versa, they significantly overlap.
Towards a Climate Friendly