U.S. Power Sector Carbon Emissions Fell  2.1% in 2008

Carbon dioxide emissions from the power sector decreased by about 2.1% as power generation declined by 1% last year, according to preliminary estimates released last week by the Energy Information Administration (EIA). The decrease reflected, among other factors, falling emissions from fossil fuel generation and an increase in wind-powered generation, the agency said.

The EIA’s preliminary estimates showed that, on the whole, U.S. carbon emissions from fossil fuels decreased by 2.8%, from 5,967 million metric tons of carbon dioxide (MMTCO2) in 2007 to 5,802 MMTCO2— the largest annual decline in energy-related carbon dioxide emissions since the administration began annual reporting on greenhouse gas emissions.

Power sector emissions—considered as a whole, rather than being allocated to end-use sectors that consume electricity—are the largest single source of U.S. carbon dioxide emissions, representing about 41% of total emissions, the EIA said. In 2008, emissions from the electric power sector decreased by about 50 MMTCO2 or 2.1%. The decrease was tagged primarily to a decline in emissions from fossil fuel generation. Natural gas–related emissions decreased 9.7 MMTCO2 (2.6%), while coal emissions decreased 24.7 MMTCO2 (1.3%).

Non-carbon generation rose by 18.6 billion kWh (1.7%) as the non-carbon share of generation rose from 27.8% in 2007 to 28.5% in 2008, the EIA said.

The economy, as measured by Gross Domestic Product (GDP), grew by 1.1% in 2008, notwithstanding the economic downturn at the end of the year. Energy demand declined by 2.2%, indicating that indicating that energy intensity (energy use per unit of GDP) fell by 3.3% in 2008. Carbon dioxide intensity (carbon dioxide emission per unit of GDP) fell by about 3.8%.

Factors that influenced the emissions decrease included record-high oil prices and a decline in economic activity in the second half of the year. Oil-related emissions declined by 6%, accounting for the bulk of overall reduction in energy-related carbon dioxide emissions.

Total U.S. energy-related carbon dioxide emissions have grown by 15.9% since 1990. Energy-related carbon dioxide emissions account for over 80% of U.S. greenhouse gas emissions.

According to the EIA, from 1990 to 2008, the carbon dioxide intensity of the economy fell by 29.3% or 1.9% per year. From 1990 to 2007 (the latest year of data for all greenhouse gases), carbon dioxide intensity had fallen by 26.4% and emissions of total greenhouse gases per dollar of GDP had fallen by 28.0%.

Source: EIA