Let's see...

2024100 MW (2018) of coal power would translate to roughly 1,76 Gt of CO2 emissions (ballparking an average of 870g CO2 / kW produced). That's 1,76 billion tonnes of CO2 - a hefty environmental price for electricity.

If the same power was produced in nuclear power plants that figure would be something like 0,02 Gt of CO2 (calculating at 0,012 kg CO2/kW) a 98.6% reduction of emissions.

Sure nuclear is more expensive, but what is a global ecosystem worth?

Food for thought.