Sorry Dan, but I struggle to see how it's not the same money. We wouldn't build enough generation from nuclear, and then build RE on top, or vice versa, so the roll out of capacities has to take the other into account.
Also if we look to the advice that the NIC gave to Government nearly 4yrs ago, they were absolutely looking at the same money and the best use for it, when they recommended the Gov scale back nuclear plans from 6 powerstations to 2, and look at the falling costs of RE and storage :-
Cool down nuclear plan because renewables are better bet, ministers told
Government advisers have told ministers to back only a single new nuclear power station after Hinkley Point C in the next few years, because renewable energy sources could prove a safer investment.
The National Infrastructure Commission (NIC) said the government should cool down plans for a nuclear new build programme that envisage as many as six plants being built.
The commission, launched by George Osborne in 2015, said that a decade ago it would have been unthinkable that renewables could be affordable and play a major role in electricity generation. But the sector had undergone a “quiet revolution” as costs fell, it said.
Sir John Armitt, the NIC’s chairman, said: “They [the government] say full speed. We’re suggesting it’s not necessary to rush ahead with nuclear. Because during the next 10 years we should get a lot more certainty about just how far we can rely on renewables.”
He argued that wind and solar could deliver the same generating capacity as nuclear for the same price, and would be a better choice because there was less risk. “One thing we’ve all learnt is these big nuclear programmes can be pretty challenging, quite risky – they will be to some degree on the government’s balance sheet,” he said.
Crucially this recommendation was made in 2018 after the 2017 CfD's returned offshore wind contracts as low as £68.55/MWh (today's monies), but before the 2019 auction that resulted in contracts falling as low as £45.73/MWh.
We've also seen storage developing, and whilst intraday storage is just one example, and typically batteries, they have a learning curve (Wright's Law, the drop in cost for every subsequent doubling in production) of over 20%. So the more that is spent on them, the cheaper they get. Just yesterday we learned that two 400MW/800MWh batteries are to be deployed in Scotland and operational in ~2yrs time - just those two batteries are roughly equal to 1/4 Dinorwig in power, and 1/7th in energy.
Over the last decade+ we've seen RE taking about 3.5%pa of the UK's leccy demand, that means every two years it matches a HPC or a SZC. In fact since the original HPC agreement/CfD was announced in 2012, RE has replaced about 35% (5 HPC's) of the UK's leccy generation, displacing FF's and their emissions. HPC may be commissioned in 2027/28, so potentially by then another 17-20% shift to RE if we keep deploying new capacity at the same rate.
If we had a binary choice between coal and nuclear, I'd take nuclear without a second's hesitation, but if the choice is nuclear or RE + storage*, and the RE is cheaper and faster, then I don't know what nuclear brings to the table? It actually looks like a negative/harmful move to direct investment into nuclear.
*TBF the choice is nuclear v's RE + (RE + storage). Sorry for the brackets, but some RE will be used as it's generated, but some will need storage, and those extra costs and complications need to be included in the calculations, just like the NIC appear to be doing.
Lastly, whilst I don't think we should look too much to the USA for financial advice, given they have taken capitalism 'a tad too far', it is interesting to note that they have an ageing fleet of nuclear reactors (almost 100), but only two replacements under construction, in fact down from four, but two were cancelled mid build when they realsied that they wouldn't be economic on completion, thanks to the falling cost of RE and gas generation, and crucially RE is now undercutting the economics of new gas generation too.
