70% is the capacity factor of the plants, not the ratio of nuclear-generated electricity in France's grid (though it's also around this value if I record well).

70% is the capacity factor of the plants, not the ratio of nuclear-generated electricity in France's grid (though it's also around this value if I record well). Nuclear can do load following: https://en.m.wikipedia.org/wiki/Load-following_power_plant#Nuclear_power_plants https://en.m.wikipedia.org/wiki/Load-following_power_plant#N... Capacity factor of 100% is not feasible because you need maintenance of the plants (probable true for every single form of electricity production). Regarding whether or not stricly 100% of nuclear in the grid is feasible, I don't now enough about grids to say whether only using load-following nuclear power plants (without hydro/gas turbines) could do the job. We have hydro in France, might as well use it rather than have only NPPs, and dams are great for load-following.