My main take away from the study is that nuclear has a role in peak and intermediate as well as base load supply, and in that sense it is a direct competitor to coal/gas rather than wind.  (The charts show extended nuclear replacing coal/gas, not wind/solar.)

The second point is that the bigger the grid the more opportunities to reduce the speed of fluctuation of both demand and supply because of the sheer scale of production consumption (which has a smoothing effect), the greater predictability of variable demand and supply (intermediate load), and as wind is less variable the greater the geographic area it is sourced from.

The main problem seems to be financial/economic rather than technical.  How do you appropriately reward providers of intermediate and peak supply which must run their plants at much less than optimal capacity and constancy.  Below capacity production and rapid variation in output have capital, maintenance and operational cost implications.  Everyone wants the highly constant high capacity utilisation demand.  

If the state as regulator and guarantor of reliability and resilience can design an appropriate tariff system to encourage maximum sustainability whilst at the same time providing adequate incentives for intermediate and peak load providers to maintain often idle capacity and expensive fast response technologies then I am sure the technical constraints (especially for new plants) can be overcome.

And on the other (demand) side of the coin, the key technology is the development of smart grids which can smooth and regulate demand (e.g. for storage heating and overnight charging of plug in electric cars) in order to optimise the use of off peak supply.  This is where incentives for consumers to utilise night rate and even more time sensitive metering to optimise  smoothing and use of base load in return for lower charges may have a role.

It is interesting that the German Nuclear industry is now advertising its capabilities in intermediate and peak load generation - presumably to bolster their case to be allowed to extend their lifespans.  They are now therefore arguing their case against coal and gas as their direct competitors and conceding that their case against wind has been lost.

notes from no w here