In most places, at most times of day, a lot less.
Why? First, because a lot of electricity is generated using wind, water, solar, and nuclear. Those don’t have that problem (ok, nuclear wastes a lot of heat, but really, who cares). The second reason is that power plants that burn stuff tend to be a lot more efficient than internal combustion engines; the best case is combined-cycle gas turbine power plants, which turn over 60% of the energy available into electricity, as compared with a gasoline engine which turns about 20% of the energy in the gas into motion.
The fuel becomes hot because the nuclear reaction in it is producing both light (eg: gamma rays) and fast-moving subatomic particles. These both interact with the rest of the fuel to heat it up.