Nuclear power works 90+% at full power base loads. The typical plant runs at 100% output for 18 months then shuts down for two weeks to refuel and shuffle rods around 1/3 are replaced the other 2/3 are moved around to even the burn out. Nuclear power is 100% renewable every year more uranium than humanity can burn up is washed into the oceans where it is in equilibrium with the subsea sediments at aleast 4ppm concentration. The USA and Japan both have technology that can extract uranium is commercial rates the reason we do not is cost. Seawater uranium is $250 lb of yellow cake , Australian mined uranium is $80 simple economics. But when the cheap easy to mine stuff runs out and the need for $250 lb uranium takes off there’s an unlimited supply in the oceans enough for billions of years of use even at a consumption rate of thousands of times what humans use every year in total energy. As humans use seawater uranium lowering the concentration in the water more leaches out of the sediments and off the land in runoff from rivers replacing what we take out. There simply is no way possible for man to deplete the uranium levels in the oceans they are too massive. As for waste I’m a geologist I can name at least 5 places in north America that have geologically stable rocks of over a billion years of stability. Deep bore hole disposal in bentonite lined holes at 4,000 meters depth with 2000 meters of concrete plug is the answer to waste disposal. Waste is a political problem not a scientific one. That’s even without going to fast breeder or transmutation reactors for deep buring the wastes before deep geological disposal. Nuclear is the only truly renewable energy source that can provide the constant and also the volume needed for modern society. Nuclear power can also make seawater into drinking water at a fraction of the cost of buring hydrocarbons to dp it let alone solar or wind. The fuel costs of nuclear are less than 1% of the total cost per megawatt hour even going from $80lb uranium to $500 the upper limit for seawater recovery only raises the cost by a few percents. This is because the raw uranium cost is only a small fraction of the cost to make nuclear fuel, even a 6x increase in raw uranium is only 1/3 the input cost of making new fuel.
Right now the economics favor terrestrial mining and once-through fuel use. But higher demand may make reprocessing and seawater extraction economically viable. Jimmy Carter implemented a national policy discouraging reprocessing. Supposedly Reagan issued an EO cancelling Carter's EO-based ban on reprocessing, but I cannot find a copy of it that has words to that effect in it. Still, it doesn't matter, the die was cast. Nobody will build a reprocessing plant worth billions of dollars if some political hack can shut down your business with the stroke of a pen.