Global Climate Change: Carbon Emissions and End-use Energy Demand

Publication Date: January 1999

Publisher: Library of Congress. Congressional Research Service

Author(s):

Research Area: Environment

Type:

Abstract:

The United Nations (Kyoto) Protocol on greenhouse gas emission reductions sets a target for the United States to achieve annual emissions of six greenhouse gases, as measured in terms of their equivalency to carbon dioxide, over the 2008-2012 period that are 7% below specified baseline years. The largest contributor to greenhouse gas emissions is the combustion of fossil fuels for energy production to power a wide variety of end-uses such as automobiles, space heating, and industrial process heat. This report presents an analysis of the potential impacts of meeting the Kyoto Protocol targets on those end-uses.

Demand for each energy source is calculated using Energy Information Administration (EIA) data and forecasts for 1996, 2008, and 2012 for 27 common end-uses making up the four major sectors: residential, commercial, industrial, and transportation. Carbon emissions are then determined using carbon-emission coefficients for each fossil fuel. Finally, energy demand reduction requirements are calculated by applying the Kyoto Protocol target of a 7% reduction in carbon emissions from 1990 levels to the 2008 carbon emission levels for each end-use.

Based on EIA forecasts, by 2008, total carbon emissions from energy use by the 27 end-uses is calculated to be 1,721 million metric tons carbon-equivalent (MMTCE) compared to 1,464 MMTCE in 1996. Five end-uses -- light duty vehicles (primarily automobiles, sport utility vehicles, small trucks, and vans), freight trucks, residential miscellaneous (small appliances and outdoor machinery), industrial machine drive, and miscellaneous commercial (communications and information equipment) -- would comprise over 70% of the 1996-2008 increase in carbon emissions.

The Kyoto Protocol target would require average carbon emissions of 1,252 MMTCE from the 27 end-uses over the 2008-2012 period if it were applied uniformly to all sources of greenhouse gases. In this case, energy demand for each of the end-uses would have to decline by about 28.7% below the levels now forecast for 2008. Further, resultant energy demand for each of the end-uses would be about 20%, on average, below the actual 1996 values. Finally, on average, the required reductions from the current 2012 forecast would be about 31%.

Reductions of that magnitude would require substantial increases in energy efficiency, above those already forecast, and/or significant reductions in the services provided by a given end-use. For example, if the target were to be met solely by increases in efficiency, the average fuel economy of the light duty vehicle fleet would have to grow from the current forecast value of about 20.3 miles per gallon (mpg) to over 29 mpg by 2008. If the reduction were to be met solely by driving less, annual passenger car (passenger cars consume about 70% of the fuel used by light duty vehicles) travel would have to drop from the current forecast of 14,500 miles per car to about 10,300 miles per car. Such actions would be a substantial undertaking and consumers are likely to feel significant effects from any strategy that is used to try to meet the Kyoto Protocol targets.