Carbon dioxide emissions from US power generation have declined by over a quarter since 2005, according to a recent report from the US government. The largest part of this reduction is from reduced demand, with switching around among fossil fuels that are less vs more dirty and adding non carbon sources combine to make about the same difference. Like this:
The following graph shows the total generation and the total CO2 output of the US electricity generation system, comparing 2007 and 2017. Solar and wind don’t show up in 2005, but are a nice little chuck in 2017 (progress but too slow). Combined, non-carbon (still with nuclear as the largest part) went from 28% to 38% at the expense of fossil fuels. Within fossil fuel, there was a husge shift from coal towards natural gas. What we need to do now is to stop switching to methane, and start switching only to wind and solar. Right now.