Focus on the chart showing tons of greenhouse gas emissions per megawatt-hour. 1913 was still in a period of rapid technological development, but the curve necks around 1930. From 1930 to 2000, GHG emissions per megawatt hour dropped from around 1.5 tons/MWh to 1.0 tons/MWh.
This is what technological progress looks like. You have periods of rapid improvement followed by a plateau with extremely gradual improvements.
Focus on the chart showing tons of greenhouse gas emissions per megawatt-hour. 1913 was still in a period of rapid technological development, but the curve necks around 1930. From 1930 to 2000, GHG emissions per megawatt hour dropped from around 1.5 tons/MWh to 1.0 tons/MWh.
This is what technological progress looks like. You have periods of rapid improvement followed by a plateau with extremely gradual improvements.