> I mean, it cannot be that wind and solar plus a few batteries are actually more expensive, could it?
Nope. The TL;DR version: It would actually be cheaper to build wind/solar and batteries, if not for the fact that the cost of building the plant was covered fifty years ago and they're getting another $1.9B in free money for it.
But of course this was never about you "missing something" - this is about you having an agenda. At least I hope it's about having an agenda, because the economics of the situation are so plainly evident you'd have to be an incredible moron to genuinely be "missing something."
For one, the plant is not owned or operated by Google. It's owned by NextEra Energy - a multibillion dollar, multinational energy company. Google's name only appears on this story in so far as they want to build data centers and that gives NextEra Energy a reason to get the plant going again. NextEra also does wind and solar power and if they had local projects that were on hold instead of a mothballed nuclear plant the story would probably be about them resuming those projects instead.
For two, the lion's share of the capital costs for the plant have already been spent long ago. The Duane Arnold Energy Center started operating in 1975. It makes a lot more sense to revive the plant that is actively losing money every day it's not operating (because NextEra still has expenses to pay on it) than to keep paying the upkeep and spend even more money building new infrastructure elsewhere.
For three, there's a lot more federal money available for NON-wind/solar power under the current administration, which is openly hostile to those technologies. $1.9B worth in this case. For the equivalent ~615MW the existing nuclear plant is expected to produce, that would be about $700M in new wind construction even if you triple it to add 24 hours worth of battery storage at 615MW (an absurd amount) you're still comparable at about $2.1B. That versus, $1.9B in basically free taxpayer loans, is not a hard decision to make.
So basically the only time it financially makes sense to go with nuclear power is when you already have the nuclear power plant and you can get a bunch of free money to put a fresh coat of paint on it.
=Smidge=