One of the things the Claverton group has discussd in great detail is how quickly UK could build things. It is pretty obvious to most people that renewables can be built far more quickly than nuclear – you just take a couple of years to build a tower, turbine and blade factory, then you can churn the stuff out. One only has to look at the WW2 precedents where Liberty ships plus a whole lot of other things – tanks, heavy guns,aircraft, concrete defences were being built at a fantastic rate.
We in the Claverton Group are only too keen to look at various future scenarios but from a fact based perspective.

I am afraid your conclusions and understanding are wrong. Andrew Smith is not a moron as he and other people in the Claverton Network have modelled in detail the interaction of renewable energy with variable supply and your statement is simply not true ie that you need 100% back up. You need to read the UKERC report on intermittency to understand this, and to look up the article on wikipedia – Intermittent Energy Energy source – http://en.wikipedia.org/wiki/Intermittent_energy_source .
If you search on this site and look up what Dr Gregor Czisch has studied exhaustively, for 7 years you will see that renewables can provide continuous electric power at the same price as power is now without 1005 back up.
Look at Dr David Elliots papers, two of them at: http://www.claverton-energy.com/?dl_id=384 and you will see various scenarios renewable energy.

see also http://nottfoe.gn.apc.org/etsu.htm
http://hansard.millbanksystems.com/written_answers/1998/feb/02/renewable-technologies

Hence you do need nuclear to provide low carbon backup for low carbon intermittent systems which is a nonsense in itself. Why bother with renewables at all if you are going to be building nuclear to provide secure supplies anyway?

response from Andrew Smith

I do discuss balancing in the article, where I provide sufficient backup mechanisms, to complement the 43GWp of zero-carbon thermal plant

Britain certainly has a renewable potential that far exceeds our current energy use. Ideally, by the year 2050 we will be delivering much of our energy from renewable sources. Unfortunately, the issue now is one of time. We simple don’t have time to wait until we can produce all our energy from renewable sources.

I’m not for a minute suggesting that we should do anything other than push renewables as hard as we possibly can. But we need to take a pragmatic look at the gap between the potential and the short term practical reality.