Even If you have a brand new coal plant, it doesnt run on its own and simple mistakes or lack of experience dealing with day to day operation will be expensive. IE a boiler can quickly get out of hand a 2000 psi when someone hits the wrong button or shorts the control power to the condensate pumps by accident and boiler feed is lost.
I recently read a WWII novel based on Midway. The author spent several chapters describing the utter complexity of refiring a boiler to make steam to move an aircraft carrier.
I had a nightmare the other night. I was back in a coal fired power plant when all of a sudden everything went wrong.
I retired in 2008 and still have nightmares of that place.