Energize Weekly, September 12, 2018
Energy-related carbon dioxide emissions in the U.S. dropped slightly in 2017 due to a combination of weather conditions, energy efficiencies and the utility industry’s steady march away from burning coal, according to federal data.
Emissions of carbon dioxide (CO2) linked to energy activity in 2017 dipped by just less than 1 percent to 5.14 billion metric tons compared to 2016, the federal Energy Information Administration (EIA) said. U.S. energy-related CO2 emissions have declined in seven of the past 10 years and are now 14 percent lower than in 2005.
The cut in emissions from coal-fired power plants was the main driver in the decline, but both coal and natural gas consumption was lower in 2017 with coal emissions dropping 2.6 percent and natural gas down 1.5 percent compared with 2016.
Natural gas carbon emissions were actually higher than those from coal as natural gas has increasingly replaced coal-fired generation—even though natural gas-fired generation emits about half the CO2 as a comparable coal-fired plant.
While coal and natural gas consumption was down in 2017, petroleum use was up, leading to a 0.5 percent increase in CO2 emissions linked to the fuel.
The decline in coal and natural gas emissions lead to the electric power sector being the only economic sector in which carbon emissions decreased in 2017. The power sector’s 4.6 percent decline was big enough to offset the increases in all the other sectors.
There are multiple reasons for the sharp decline in power sector emissions. The shift to cleaner burning natural gas and the increase in carbon-free renewable energy helped cut emissions. Natural gas is also more efficient than coal, typically using less energy than coal plants to generate each kilowatt-hour of electricity.
Electricity sales also posted the largest drop since the economic recession of 2009, in large part due to mild weather. A cool summer and mild winter reduced the commercial and residential demand for air conditioning and heating, the EIA said.
Electricity sales to the industrial sector were also lower in 2017, even as overall manufacturing output increased. This again reflects an ongoing trend in increased energy efficiency in manufacturing and the economy in general.
From 2005 to 2017, the U.S. economy grew by 20 percent, while U.S. energy consumption fell by 2 percent. Energy-related CO2 emissions also decreased during that time period, dropping 14 percent between 2005 and 2017. “Compared with the levels in 2005, U.S. economic growth in 2017 was 29 percent less carbon-intensive, and overall U.S. energy consumption was 12 percent less carbon-intensive,” the EIA said.
