Big power generators like nuclear and coal plants are like seagoing tankers--difficult to turn around. As \u201cbaseload\u201d plants, they run 24\/7. When they\u2019re on, they\u2019re on. The grid doesn\u2019t need their power all the time. The California Independent System Operator\u2019s market pays generators to back off power in the wee morning hours, for instance. Nuclear power is wasted during those times because it cannot be ramped down. Last month, for instance, negative bids into the market were at a nadir of -$30\/MWh at 3 a.m. That was one major reason electric vehicles were floated a decade ago--as a way to use excess baseload power in the middle of the night to charge up car batteries. Electric vehicles still do that, but politically, they are sold to the public to use renewable generation. If nuclear plants were shut down, there would not be the same degree of overnight excess power. If utilities were to procure replacement power for Diablo Canyon and San Onofre, it would cost consumers $260 million\/year for Diablo and $753 million\/year for San Onofre, according to California Public Utilities Commission data.