The EU has much higher pricing of CO2 (currently at 60 eur / tonne [0]) and yet Germany was using more coal power than expected, forced by the fact that there was a scarcity of wind. [1]
Of course, that caused the prices of electricity for households to jump up. [2]
Carbon Tracker calculates that the majority of coal plants in Europe are already cost negative.[1] They live off uncompetitive tariffs and subsidies. Germany's reverse auction for coal plants over the last year ended up accepting a lot of very low bids, as coal owners were desperate to get out from under stranded assets. Even they were widely criticized as over-priced given the state of the industry.
[1] https://carbontracker.org/cop26-a-chance-to-reset-and-elimin...