That "source" is complete BS. It is a theoretical model that models LCOE (Levelized Cost of Electricity), pure generating cost. It does says nothing about the real world, nor does it model the cost of electricity, which has to include system costs. See
https://en.wikipedia.org/wiki/Levelized_cost_of_electricity#...
Those system costs rise dramatically with the share of intermittent renewables in a grid, making LCOE almost completely meaningless and downright misleading for such a grid. Full Levelized System Cost of Electricity is a better measure.
https://www.sciencedirect.com/science/article/abs/pii/S03605...
The discrepancy can also be seen in the real world, where despite falling generating costs for intermittent renewables, electricty prices correlated extremely strongly with the share of intermittent renewables in a grid.
The check against the Real World™ is also another item where this Fraunhofer piece of disinformation fails. They claim costs of 13-49 cents for nuclear.
However, in the Real World™, nuclear power plants profitably produce for 3-5 cents in Switzerland (world-renowned for its low, lower, lowest prices!).
So something very obviously does not add up.
When you look at the model more closely, you see exactly what doesn't add up: all their assumptions going into the model are lopsided, to the point of being absurd:
1. For construction costs, they take as the baseline not the average of current construction costs, nor the median either. They take the highest construction costs seen up to that point. As the baseline. And then increase it. This statistical malpractice even without knowing any details. And the details make it even more ridiculous: their baseline is a FOAK build (prototype), the reactor design (EPR) has been discontinued by the manufacturer, because it was too hard to build, and the country (Finland) had to rebuild its nuclear construction know how.
2. For the lifetime of the plant, they assume 40 years. Nuclear reactors in the US, for example, are all being extended to 80 years, which is also the design lifetime of modern reactors. This obviously doubles the Capex per kWh produced.
3. They assume comically low utilization down to only 20% capacity factor. For references, the US nuclear fleet has a capacity factor of over 90%, as did the German fleet. The reasoning they give is that they want nuclear to run only as a backup to the intermittent renewables. Which is ridiculous, because it allows the intermittent renewables to shift the cost for their intermittency onto nuclear.
4. They also assume much higher capital costs than they do for intermittent renewables. Not sure how they justify this, possibly with the fact that the guaranteed subsidies for intermittent renewables make them a low risk.
5. To balance things out, they assume higher utilization rates for wind and solar than have ever been achieved in the Real World™. And those utilization rates are decreasing, not increasing.
Put those components together, and you get around a factor 10. So this "study" makes assumptions that result in nuclear looking around 10x more expensive than it should be. Which, surprise surprise, pretty much matches the discrepancy between what this study shows and the evidence from the real world.
Just for LCOE.
You then have to add the system costs.
Pretty much the entire rest of the industrialized world are getting into nuclear, expanding their nuclear programs or even ditching their nuclear exits (the most recent: Belgium and Taiwan, with Switzerland on the cusp). There is a pledge to triple nuclear power endorsed by essentially all the economic powers in the world, and they are also following through.
Germany will get there in the end, but we have always been more stubborn in insisting on our mistakes. The longer it takes, the more expensive it will be.