With current technology, nuclear is significantly less efficient than solar and wind in one very important metric: cost. Or to put it another way, a dollar invested in solar or wind will produce more energy and offset more carbon emissions more quickly than if that dollar was invested in nuclear.
This may change when we're chasing after the last 10-20% of grid emissions, but for now there's still a lot of low-hanging fruit.
And once you install enough storage to make the 9's comparable, the solar/wind is quite a bit more expensive than the nuclear.
But power stations are contracted/paid on the basis of the energy (ie MWh) they generate. And solar and wind can produce each MWh significantly cheaper than new-build nuclear can.
But will they be continue to be paid by the solidified alumunium smelter and the gunged-up paper mill the week after the cloudy weather?
That said, in interesting innovation that may deal with dispatch-ratio limitations of renewable energy has become popular here in Africa for domestic lighting.
As you know, we have 'moved on' from electricity to candles and bush-fires for reasons relating to what is euphemistically called a skills-shortage.
Many of us are now using LED light bulbs with batteries in them. They charge when the power is available (Deo Volente) and offer ~4 hours light.
And we get to see the stars now.
https://www.energy-storage.news/news/developer-8minute-says-...
https://www.energy.gov/ne/articles/nuclear-power-most-reliab...
Building nuclear in 2021 is like buying UltraSPARC in 2021. Sure, it's more reliable than a single PC, but a cluster of PC's is way cheaper and more reliable in aggregate.
As an example, the large solar facility in Arizona produces 15% of the power in January, as it does in June. The batteries or overbuild needed to compensate for this tremendous imbalance in power production can only be offset with absolutely staggering scaled batteries.
...something that never seems to be modeled in the articles pushing renewables.
Rolling blackouts are incredibly abnormal, but would be extremely common with solar/wind based power.
A diversified power grid would still be subject to weather - which is common across the entire local grid.
This is not at all clear, especially going forward. The key is to shave off the last 10% or so with hydrogen and combined cycle, not batteries.
https://model.energy/ for actual model results
How long do you think it takes to "recycle" a nuclear power plant after it finishes operation? Decommissioning an old nuclear power plant can take more than 100 years and costs billions.
Decommissioning and clean-up of the UK's fleet of 17 retired Magnox reactors, built between the 1950s and 1970s, is estimated to cost in excess of £100 billion, and will still be ongoing well into the 22nd century:
https://www.world-nuclear-news.org/WR-UK-nuclear-clean-up-co...
Is it really fair for us to keep offloading these costs and problems onto future generations?
Have a look at France - they get over 70% of their electricity from nuclear just fine. And it is much cleaner and cheaper than in Germany which opts for Russian gas instead.
That either means a gargantuan cost to build new plants (making germany's recent renewables building spree look cheap) or trying to make a plant that was designed for 80 years last 100 with all of the exciting safety concerns which go with it.
Even France has cooled on nuclear due to the high costs involved. As old reactors are decommissioned, they plan to replace them mainly with renewables:
https://www.power-technology.com/comment/renewable-energy-to...