Quantifying the causes of the recent decrease in US CO2 emissions

Energy Matters:

Between 2007 and 2015 total annual US CO2 emissions decreased by 740 million tons (12%). An updated analysis shows that 35% of this decrease was caused by natural gas replacing coal in electricity generation, 30% by lower fuel consumption in the transportation sector, 28% by renewables replacing coal in electricity generation and 7% by other factors. The 515-million-ton (20%) decrease in electricity sector emissions between 2007 and 2015 was 50% attributable to natural gas replacing coal, 40% to renewables replacing coal and 10% to other factors. These estimates do not allow for the impacts of the 2008-9 global recession on emissions growth, which could have resulted in annual US CO2 emissions now being as much as a billion tons less than they otherwise would have been. This estimate is, however, speculative.

In previous posts here and here Euan Mearns and I made approximate estimates of how much of the recent decrease in US emissions was caused by what. I came up with this:

Cont....