The potential for energy-efficient technologies to reduce carbon emissions in the United States: Buildings sector

Energy is used in buildings to provide a variety of services to users such as lighting, space heating and cooling, refrigeration, and electricity for electronics and other equipment. In the US building energy consumption accounts for nearly one third of total primary energy consumption and related greenhouse gas emissions. The cost for these energy services, or end-uses, was over $200 billion in 1997. This paper summarizes a detailed assessment of the achievable cost-effective potential for reducing carbon dioxide emissions in 2010 in the US residential and commercial buildings sector based on the preliminary results of a study completed by the authors for the US Department of Energy (LBNL, ORNL, ANL, NREL, and PNNL, 1997). The authors analysis shows that substantial reductions in future greenhouse gas emissions can be realized through the use of more energy-efficient technologies and processes at a net reduction in the total cost of energy services. In an efficiency scenario, in which renewed efforts are undertaken to promote energy efficiency through enhanced public and private-sector R and D and market transformation activities, energy use drops by 1.9 quadrillion Btu (5%) from business-as-usual (BAU) levels and carbon emissions decline by 25 MtC (4%) from BAU forecasted levels. This represents a savings of $18 billion in fuel costs in 2010, which is purchased with an annualized incremental cost of $7 billion in efficiency improvements. In a high efficiency/low carbon scenario, which reflects an even greater commitment to reduce carbon emissions, results in 4.0 quads (11%) less energy use and 91 MtC (16%) fewer carbon emissions than the BAU scenario in 2010. This high efficiency/low carbon scenario represents a savings of $33 billion in fuel costs in 2010 resulting from an annualized incremental expenditure of $14 billion on efficiency improvements