I work at a company that makes the main parts for powerplants... gas turbines, generators, and steam turbines... the base load units operate constantly for thousands of hours continuously, and when they are shut down for maintenance, usually have lots of work to be accomplished, inspections to be made, parts to be replaces, and all on a very tight schedule to minimize the time not making power. And these machines are enormous... the gas turbine (which is basically a jet engine) alone is the size of a locomotive car... these would be HUGE fixes!