A new University of Michigan analysis of U.S. government data shows the transportation sector will likely surpass the electric power industry as the largest source of carbon dioxide emissions, MIT Technology Review reports.
As natural gas and renewable resources have displaced coal-fired generation, power sector CO2 emissions have dropped on average 2.8% a year between 2007 and 2015.
CO2 emissions from the transport sector have increased at an average rate of 1.8% per year over the past four years as increased travel and shipping have outpaced efficiency gains.
The 2008 financial crisis coincided with low natural gas prices that resulted in a shift away from coal fired generation in favor of gas alongside a drop in power generation, especially among industrials. As the economy recovered, the shift away from coal persisted, bringing continued reductions in power sector CO2 emissions.
The economic downturn also depressed transportation activity, but continued low oil and gasoline prices combined with the economic recovery has resulted in brisker sales of trucks and SUVs and miles driven.
The shift is a reversal of a decades long trend, noted John DeCicco of the University of Michigan Energy Center. Power sector CO2 emissions have been greater than those from transportation since 1979, DeCicco wrote in the report. Emissions from both sectors peaked in 2007, and then declined as a result of the financial crisis. But while the trend in power sector emissions continued to trend downward, transport sector emissions have resumed rising, he noted.
If the Obama Administration’s Clean Power Plan (CPP), aimed at curbing CO2 emissions from power plants, is put into effect, that would hasten CO2 reductions in the power sector, widening the gap with transportation, DeCicco says.
DeCicco concludes that “existing policies will not suffice to reduce transportation CO2 emissions as much as electric sector CO2 emissions are likely to be reduced by the CPP.” Therefore, he argues, “additional measures will be needed to address transportation in the decades ahead” such as greater vehicle efficiency and carbon offset measures such as afforestation."