Honestly, better than gas. Like, yah, natural gas has lower co2 per unit of power at the power plant, but there’s methane leaking all along the supply chain, a green house gas 40 times more potent than Co2.
between 5-10% of the methane that comes out of a well ends up leaking somewhere along the line. To make the heating effect even break even with coal the leak rate would have to be closer to 1%.
Not advocating to keep burning coal, just saying that what we’ve been replacing it with is worse. I’d rather we keep a coal plant open and wait for an opportunity to replace with with a non-carbon emitting power source than build a shiny new gas plant that’s going to be kept around for at least 20 years.