There are functioning Thorium based Molten Salt Breeder reactors, which for ~50MW can be built in a shipping container size - they are small, so can be deployed at local sites, thus reducing transmission losses, much harder to use for weapons (thats why the world tilted towards the use of uranium reactors in the first place), dont need prior enrichment, and can use much higher percentage of the fuel - so much less waste product. Also since the whole stuff is a molten salt, you just drain it from the reactor core and the reaction simply comes to halt.
The technology works, as it was tested when they were deciding if the industry goes with uranium or thorium, but the war lobby win out unfortunately, as they wanted a source for their nuclear weapons, at which the Thorium reactors are not great.
And yes, nuclear is super clean even if we compare it with solar+wind batteries not even counted in to the equation. BTW you can use "spent" fuel rods from conventional nuclear plants in a breeder reactor, to further diminish waste and use them up. https://en.wikipedia.org/wiki/Thorium-based_nuclear_power
You can make Thorium reactors much smaller and cheaper, basically a 50MW unit is not much larger than a shipping container, while being much more safe than standard nuclear plants. The largest issue is over-regulation of the nuclear power in general.
A 50MW of solar installation is HUGE, and thats 50MW at the sunniest part of the planet: https://newsaf.cgtn.com/news/2019-12-15/Kenya-launches-Chinese-built-50MW-solar-power-plant-MqC575l6Te/index.html, We are basically talking about close to a square kilometer installation...
there is simply no way to call a 50MW solar plant cleaner than nuclear and its probably not even that much cheaper in the end. Compare that to a shipping container sized reactor... Only thing in the way, is the nuclear scare and government regulations.