September 2018U.S. Energy Information Administration | U.S. Energy-Related Carbon Dioxide Emissions, 2017 iThis report was prepared by the U.S. Energy Information Administration (EIA), the statistical andanalytical agency within the U.S. Department of Energy. By law, EIA’s data, analyses, and forecasts areindependent of approval by any other officer or employee of the United States Government. The viewsin this report therefore should not be construed as representing those of the U.S. Department of Energyor other federal agencies. September 2018U.S. Energy Information Administration | U.S. Energy-Related Carbon Dioxide Emissions, 2017 2Table of ContentsIntroduction .. 3Overview ....... 4U.S. energy-related carbon dioxide emissions decreased 0.9% in 2017 . 4Even though energy‐related CO2 emissions decreased in 2017, emissions growth was 20 million metrictons above trend ... 5Fuels .. 6Natural gas CO2 emissions continued to exceed those from coal in 2017 .......... 6End-use sectors ......... 7Of the four end‐use sectors, only transportation CO2 emissions increased in 2017........ 7The 2017 increase in energy‐related CO2 emissions from the transportation sector was led by jet anddiesel fuel—motor gasoline CO2 emissions declined ...... 8Commercial sector energy‐related CO2 emissions declined in 2017 ....... 9Residential sector energy-related CO2 the lowest since the late 1980s ........... 10Natural gas is becoming the dominant industrial emissions source ...... 11Electricity generation .......... 12Natural gas replacing coal-fired generation and increasing generation from non-carbon sources haveled to the decline in the carbon intensity of electricity generation in recent years ..... 12The increasing share of non‐carbon electricity generation has lowered the carbon intensity ofelectricity supply in recent years ........... 13Growth in wind and solar electricity generation has resulted in the decreasing carbon intensity of theelectricity supply14Table 1. Weighted factors for electricity and primary energy by sector for the energy‐related CO2emissions, percent change from 2016 to 2017 ......... 15Table 2. Carbon dioxide emissions from the generation of electricity in the commercial and industrialsectors ......... 17Future implications of the 2017 decline in CO2 emissions . 18Terms used in this analysis .. 19Methodology used in this analysis .. 20 September 2018U.S. Energy Information Administration | U.S. Energy-Related Carbon Dioxide Emissions, 2017 3IntroductionThis analysis examines the economic trends and changes in fuel mix that influence energy-relatedcarbon dioxide (CO2) emissions.Year-to-year trends can be influenced by the weather, relative prices ofprimary fuels, and planned and unplanned outages of electricity generation capacity.Longer-termtrends are influenced by policies to encourage renewable energy, reduced costs and improved efficiencyof new technologies, and demand-side efficiency gains such as vehicle miles per gallon or applianceefficiencies.Energy-related CO2 emissions result from fossil fuels combusted for their energy content orused as non-energy inputs to the petrochemical and related industries.。。。。。。