Efficiency isn't the same carbon/NO2/whatever emissions. A lot of inefficiency comes from waste heat and mechanical losses (that's true both in electrical gener

Efficiency isn't the same carbon/NO2/whatever emissions. A lot of inefficiency comes from waste heat and mechanical losses (that's true both in electrical generation AND gas/diesel engines of course) and even then fossil fuels only make up 75% of US power. Now that said the overall win is still probably smaller than marketing would be willing to admit.