The problem is that a nuclear accident would kill a lot of people immediately with no warning.
To try and justify that statement with evidence, try and make a list of all the people in the world ever killed as a result of nuclear power.
The peak, measured in GW, is not a fundamentally important factor since renewables output is fairly predictable in the short term (hours). Certainly the UK's hydro is sufficient in that respect.
Be careful switching around hydro and "renewables" interchangeably.
Hydroelectricity is reliable, dispatchable and predictable, much more so than the other technologies that get lumped together under "renewable".
Along with nuclear power, hydro accounts for most of the dispatchable, predictable, scalable clean energy in the world.
It's generally worth considering it as its own category when looking at clean energy, rather than lumping it together under "renewable".
Anyway, "renewable" is a pointless marketing buzzword, a brand name for an ideology.
Does it mean anything, does it have a consistent definition, technically? No.
The energy content of a closed system is never "renewable" - that's the second law of thermodynamics.
It's just a brand name for an activist ideology of excluding nuclear power as well as excluding fossil fuels, it's a brand for their ideologically "acceptable" technologies.