‘Wind, hydro, and solar projects generated more electricity than gas fired power stations this winter, providing enough clean power to meet all household demand and helping to significantly reduce gas imports’. So said the Energy and Climate Intelligence Unit recently.
Dr Iain Staffell from Imperial College London also said the UK was doing very well given that ‘electricity is the only form of energy where we produce more than we consume - in comparison to our coal and gas requirements where 60-75% are still imported from abroad.’ For example, as his report for Drax indicated, on 30th December, Britain had a record of 3GW of surplus clean power produced – clean power sources produced more than 26.4GW while demand was only 23.4GW.
However, the term ‘clean power’ includes nuclear power, not just renewables, and not everyone sees that as ‘green’ or sustainable. While the likes of Boris Johnson and Grant Shapps, are very pro-nuclear, the story on the ground is more uncertain, with, as I noted in an earlier post, costs rising for new plants and project delays mounting. There is also the issue of whether it’s actually needed. In what might be seen as an extreme view, in a recent article, Prof. Wade Allison, said ‘nothing is greener than nuclear – and it is the only way to zero,’ adding that ‘investment in large scale primary renewables should cease immediately’. Dr Paul Dorfman countered with the claim that ‘nuclear isn’t just too slow and expensive to help with our climate and energy crises, it’s also too inflexible to power up and down with the swings of demand’. So he backed renewables.
It should hardly need to be pointed out that renewables are booming, while nuclear has almost flatlined in most places. And there should be little need to repeat the standard and by now familiar case against nuclear. But it’s still believed by some that we will need at least some nuclear to ‘back up’ variable renewables. It’s hard to see how this would work. Do we keep a few nuclear plants off-line for occasional start up and use when renewable supplies are lower than demand? Or run the nuclear plants throttled back, to ramp up to full power when more is needed? Either way, that would be very costly and difficult- nuclear plants need to be run flat out to pay back their high costs, and they can’t be ramped up rapidly, safely and regularly.
More flexible nuclear plants might possibly be developed (it is claimed that some small modular plants could do that), but they would be expensive to run in that mode. We could convert some surplus nuclear electricity into hydrogen and store it, ready to meet lulls in renewables, but using surplus renewables to make storable green hydrogen would arguably be more logical, and a cheaper way to meet long or short term power shortfalls. In parallel, in addition to other types of short and long term flexible storage, rather than investing in nuclear, it would also make sense to improve demand management, heat loss capture, and energy use efficiency, all of these enabling the more flexible and cost effective use of energy.
The basic point is that, as has been repeatedly argued, we have to move to a more flexible power system, which nuclear can’t deliver. For example, in the UK context, at present, in summer at night, power demand can fall to be met by around 20GW of power plant. But we already have over 50GW of renewable capacity, plus some flexible gas plant capacity and a bit of storage. Plenty enough for now for balanced output. So, although the capacity market has been tweaked to subsidise some old nuclear plants, we don’t actually need them to cope with what is sometimes called 'base-load' demand- the minimum that aways has to be met.
The total level of winter power demand will of course rise, if and when electricity takes over from gas for heating, although some green heating can be provided direct via renewables (biomass, solar, geothermal) using local heat networks and possibly some flexible co-generation of heat and power. But whatever the exact energy use type and sector mix, and the level of energy conservation consumers are willing to accept, and thus the final resultant level of winter power demand, the UK’s current plan is to have 24GW of so called base-load nuclear in place by 2050, with almost all the rest coming from renewables, maybe 250GW or more, replacing most fossil fuel plants. Many of the renewables would be variable, so there is no way 24GW of nuclear would be enough to try to meet the occasionally long shortfalls in winter. But the surplus from renewables at other times, stored as hydrogen and also in other forms, could do that. Along with demand management and energy efficiency, that should make nuclear irrelevant in terms of grid balancing.
It gets even worse in summer, when demand is lower. Although there may be an increasing air-conditioning load, PV solar output will be higher. But whatever the demand level, presumably, in 2050, all the proposed 24 GW of nuclear would have to be used, so as to justify the high nuclear plant/power costs, while much of the renewable capacity would have to be switched off, despite it being cheaper. It’s a crazy way to use assets. Though, of course, it wouldn’t have to be like this - there would be plenty of stored green power for back up, and no need for nuclear for balancing.
So what then is nuclear for, given that it would arguably be easier and cheaper to use the surplus renewables, along with flexible demand management, for grid balancing around the year? With that, we don’t need nuclear base-load. Or any sort of fixed base-load supplying plant. Although, Wade Allison suggested, you could try to run the whole system on nuclear, with some interim fossil backup. Good luck with that. And with carbon capture and storage to allow for the continued use of fossil generation. Despite all the hype, fossil CCS is going rather slowly. And even if emissions can be cut to some extent, adding CCS will add cost and reduce fossil plants operational flexibility. It does at times seem odd the lengths nuclear and fossil advocates will go to see off what increasingly looks like the answer- renewables for balancing, across the board! Though in terms of supply, the air transport sector looks a bit tough….but that’s another story.
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