Nuclear is probably the most expensive energy source for powering a grid at present, and nuclear advocates have tried to get around this by calling for deregulation, but that's just not plausible. Given the catastrophic failure mode of nuclear power, the plants have to be over-engineered relative to all other power systems, and that greatly increases costs.<p>Let's take Fukushima as an example. If they'd just put the emergency diesel generators (very heavy) on the roof of the plant rather in the basement, there'd have been no hydrogen explosions and meltdowns, as the seawater would not have destroyed them. However, this would increase the plant's cost due to the need for greater structural stability for such a configuration.<p>Not only that, uranium fuel rods are expensive to manufacture and expensive to handle, and storing them after retirement is another long-term cost. Granted the ~21 tons of uranium fuel consumed per year in 1 GW output nuclear complex is much less that the equivalent ~4.2 million tons of coal in a 1 GW output coal plant, but the preferable option is a solar/wind/storage system that consumes no material at all (not counting battery maintenance and turnover, I suppose, but there are recycling options). On top of that, if demand is high uranium prices can fluctuate wildly as the pre-Fukushima years demonstrated.<p>So, let's agree there's no reasonable argument for cutting costs on nuclear due to the various scenarios (terrorism, accident, sabotage, cybersecurity, etc) that could lead to catastrophic failure. If the goal is to maintain a reliable electricity grid in a fossil-fuel free world (and even grow it as electricity replaces crude oil and natural gas for transportation and industry), it's hard to argue that nuclear is a better option than wind/solar/storage deployed at scale.<p>Of course, you need a lot of wind/solar/storage to equal the output of a 1 GW nuclear complex, and at present costs for reliable 24/7 year-round output from the two systems are roughly comparable. In the long run, however, the former is the far better option.