this post was submitted on 07 Aug 2023
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@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Short term storage already exists. So does wind, solar, at considerable (though inadequate) scale, and cheap (bottlenecked mainly by grid connection). Dynamic demand exists to some degree and so do interconnectors.
Lithium batteries exist at reasonable scale in other countries, notably 2.5GW on California's grid. There are active trials of V2G but IMHO reasons to doubt how big a contribution it will be. Reusing EV batteries as grid storage exists at a small scale.
Nuclear power plants take forever to build, in recent experience in the UK. Even National Grid doesn't believe the government's promised 24GW of nuclear will be done for 2050.
There are uncertainties whichever way you go. So we need several strategies. However, it's worth pursuing iron-air batteries and possibly hydrogen as well as nuclear. But arguably they are only needed for the last few percent anyway. And I will *not* accept any attempt to slow down installation of renewables in favour of nuclear.
Decarbonisation, in terms of electricity in the UK, has been achieved through both nuclear and renewables. Fossil fuels are down to 40% of total units generated.
Figures for the last year in the UK:
Source GW Percent
Coal 0.32 1.1
Gas 11.30 38.3
Solar 1.38 4.7
Wind 8.82 29.9
Hydroelectric 0.34 1.2
Nuclear 4.44 15.0
Biomass 1.49 5.0
Unfortunately nuclear plants are closing rather rapidly, and it will be some time before replacements are online.
PS IIRC there are plausible sources saying that you only need renewables equal to ~3x plus short term storage. Both aspects of this are technically feasible and proven today. But obviously it means more rare earths etc. More nuclear, or more long term storage, or more interconnectors etc, reduce the cost.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis So no, nuclear is not the only proven option by a long way. Nor is it a feasible option on its own IMHO. And new designs increase risk and time. Building multiple reactors to the same design saves time and money, of course.
Nuclear is an option. It probably isn't enough on its own any more than any of the other options are. There is absolutely no reason to stop building renewables, and slowly scaling up various storage options, today.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Also on the timescale: Labour have officially said they would reach 100% clean electricity by 2030, starting in 2025. That's generally seen as challenging, but it may well be possible (albeit at a high cost in lithium and rare earths). There's no way it can be done with nuclear. In any case we need to move fast; most of the rest of the transition depends on clean electricity. My main objection to nuclear is simply that it will take another 20 years to get maybe 3 more reactors if we're very lucky.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
I'm not saying 100% nuclear would be best, but I /know/ that 100% volatiles + storage + transmission are practically impossible.
Up to around 40% volatiles can be compensated by a large grid. The rest can, with current or near-future technology, be nuclear and/or hydro. With middle-future technology, this /might/ be gradually replaced by more volatiles+storage+transmission.
@MattMastodon @matthewtoad43 @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
This is just the fact: there are, at the current state, only two energy sources that can form the backbone of a decarbonized grid, and they have proved it, hydro and nuclear.
Hydro is not available everywhere, however, as it has really large area demand, and geological requirements.
And I repeat: nuclear /is/ very capable of load following.
And I repeat: batteries at the needed scalability don't exist (yet?).
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis As I already mentioned, California has 2.5GW of batteries today. And credible half hourly models suggest that you only need hours of storage to get up to approximately 98%.
There are lots of ways to solve intermittency. Nuclear is one strategy that potentially works, but still needs short term storage - modern designs can vary load, but not quickly.
3x renewables plus a few hours storage is likely fine. So is a lot of nuclear. Hydrogen or iron-air *might* make the whole thing much cheaper, but indeed are immature technologies. More interconnectors are mature technology that always makes it easier, but are not enough on their own; dynamic demand is helpful and semi-proven.
But building "too much" renewables while we wait for nuclear is fine. Because most likely that nuclear will never be delivered. At least not in the UK. And as I understand it the supply chains don't really overlap. But above all because *it's the total carbon emitted that matters*. We're on a deadline.
I see no obvious reason to expect that the UK can build large amounts of nuclear quickly, even if there was the political will to do so. Successive governments have tried and failed. On recent progress, by 2050, if we're lucky, we might have 3 more 3GW plants running, which is nowhere near current demand, let alone future demand with electrification.
Even if the government meets its own target of 24GW by 2050, which seems extraordinarily unlikely given the slow progress so far, that will be a lot less than the total peak demand given electrification. So you still need storage.
So I'm not going to campaign to stop building renewables on the basis that one day we *might* build more nuclear.
Having too much renewables is *NOT* a problem, especially when compared to nuclear that will probably never materialise. Worst case, switching off wind and solar farms is much easier than switching off nuclear reactors. Best case, we can export that energy, use it for intermittent energy intensive industrial processes, or store it.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis What you say about "40% volatiles" is a myth.
Currently we (UK) always run at least ~3GW of fossil fuels, as well as a surprisingly variable amount of nuclear, because of the inertia problem. That will be solved by 2025.
https://www.nationalgrideso.com/electricity-explained/how-do-we-balance-grid/what-inertia
Britain is up to 36% renewables *on average* over the last year, and still building fairly quickly. Plenty of countries have much higher proportions of renewables. But they also have other ways of dealing with it, e.g. Denmark's trick was always much more energy trading.
Iceland is 86%, Norway is 76%. It can be done, though these figures are inflated by geothermal and hydro, which may not be viable for the UK. Sweden is 63%, but that includes a fair bit of biofuels. California is already up to 59%.
Intermittency is a problem, there are lots of ways to manage it. Nuclear is one of several options.
The amount of lithium batteries needed to reach 100% is probably ecologically unreasonable, although several academic studies do talk about this. So we probably do need some nuclear, unless iron-air batteries or hydrogen pan out rapidly. Nonetheless, the idea that there's a ceiling of 40% is way out of date.
https://www.euronews.com/green/2023/01/20/which-european-countries-use-the-most-renewable-energy
https://www.govtech.com/smart-cities/california-hits-new-record-for-renewable-energy-generation
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
There are already single events of more than a few hours where sunshine and wind are lacking. But that is only the immediate perspective; you need to integrate over at least several years to see the longer-term shortages that need to be handled as well. And that is quite obviously much more than a few hours. Therefore, I have some problems regarding such studies as credible.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Interconnectors make the "long term no wind in winter" scenario much less likely, though obviously this varies depending on the country; there's less opportunity for it in Australia, but on the other hand it's just much bigger - "long range" may be within the country.
As I understand it the Australian study was based on real world data.
But let's say you're right. After all the study accepted that 2% of the time it's not sufficient. You have a few options for that last 2%. One is more nuclear - not necessarily 100% nuclear, or even 40% nuclear, but enough to prevent any freak weather events from causing serious harm. Another is hydrogen - an immature technology that is nonetheless 50+ years old.
There was a European study ... I think I lost it on X though. That specifically made the case for hours not days. But to achieve that you have to over-build.
Really one of the biggest arguments for nuclear is that over-building renewables makes a minor problem with rare earths into something much more serious.
Most likely we need either some nuclear or some long-term storage. Long term storage means immature but clearly technically feasible technologies: hydrogen or iron-air, maybe a few other candidates. Against that you have the fact that with the exception of France in the 1980s, building large amounts of nuclear power quickly has almost never happened.
Nuclear just takes too long. So use it for what it is - a modest amount of baseload power at roughly twice the cost of renewables.
Let me see if I can find some of the sources ... I already posted the study on Australia.
Here's a Scottish one, they concluded that over-building renewables is feasible. Also arguing for some more hydro. Unfortunately hydro is generally considerably dirtier than nuclear.
https://scottishscientist.wordpress.com/2015/04/03/scientific-computer-modelling-of-wind-pumped-storage-hydro/
http://re100.scienceontheweb.net/
https://scottishscientist.wordpress.com/2017/07/14/wind-storage-and-back-up-system-designer/
Here's the National Grid's view; IIRC they are skeptical about the claim of 24GW of nuclear by 2050, but their models say it won't be enough on its own anyway and bet on hydrogen.
https://www.nationalgrideso.com/document/263951/download
Here are some of the numerous academic-ish sources, probably out of date. As I said, system models often assume there is infinite lithium, so doubtful IMHO.
https://web.stanford.edu/group/efmh/jacobson/Articles/I/145Country/22-145Countries.pdf
https://twitter.com/AukeHoekstra/status/1557466581185224704
https://www.helsinkitimes.fi/themes/themes/science-and-technology/22012-researchers-agree-the-world-can-reach-a-100-renewable-energy-system-by-or-before-2050.html#.YvPUxCrrWdI.twitter
https://ieeexplore.ieee.org/document/9837910
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis It is well worth reading the original Australian model.
That has 60% wind and 45% solar, with hours of storage, including some hydro, reaching 98%, using real world data (and scaling the output of existing plant). Going from 105% capacity to 170% eliminates the problem entirely - assuming no freak weather events not included in his ~ 1 year trace. Equally you could solve it with long-term storage. Long-term storage doesn't have to be cheap or efficient per kWh; it's the capital cost, the ecological cost (e.g. hydrogen leaks), and whether it's feasible at all, that's the real question.
https://reneweconomy.com.au/a-near-100-per-cent-renewables-grid-is-well-within-reach-and-with-little-storage/
If you don't have nuclear equal to your *PEAK* demand, which looks unlikely on any reasonable timescale, then either you need quite a bit of storage, or you need to accept there will occasionally be power cuts for non-essential users.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis But the fundamental thing for me is I won't wait for new nuclear.
We need to cut carbon emissions *NOW*. That might mean starting some new nuclear power projects. But both renewables and short term storage are being installed today, cheaply, and while there are some obstacles to this (e.g. grid access), balancing is not the main problem.
We can't use nuclear as an excuse any more than we can carbon capture.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
If you don't have power output from storage equal to *PEAK* demand, it's the same argument for any storage. And storage doesn't /produce/ energy, it /consumes/ it (because of conversion losses, which are significant).
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Nuclear does not avoid the need for short-term storage to cover the peaks, unless you can build vast amounts of it (equal to peak).
Nuclear *does* avoid the need for long-term storage, if you can build enough of it (equal to average).
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
You seem to argue that our /current/ fossil grid would also need more storage, but it works just fine as is. Nuclear is better at load following than fossils, so what gives?
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis The fossil fuel grid we had 20 years ago relied on gas peak plants and hydro for peaks.
Nowadays we have diesel farms (eeek!), and increasingly (thankfully!) batteries.
The actual UK grid today is only 45% fossil fuel (and some nations and states are better than that). We also have more interconnectors than we had in the past.
UK nuclear has generally been used as baseload for many decades.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Sadly it is much easier to build an extra 10GW of peak gas plant than it is to build an extra 10GW of nuclear plant. The tradeoff is of course that the gas plant is inefficient and therefore extremely expensive per unit generated (but not used very often). Not to mention destroying the planet.
But that is how we largely managed it in the past.
In the future, and even the present, fortunately we have better options.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Ah, but historically, France is not an outlier. Here are the largest 10-year deployments of clean energy sources. The green ones are nuclear.
Nuclear doesn't take long.
Here is an overview of historic build times.
The task is not fearing we might get a bad case, but creating an environment in which we get a good one.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis That graph includes some huge deployments of wind, and today, it's a mature, cheap technology (though still improving). Same with solar.
On the timescale on which the historic installs occurred, that was not the case: nuclear and hydro were the only mature options.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Can you name *one* nuclear project in the last 20 years in Europe that wasn't severely over-budget and severely delayed?
It's not just the UK. Every third gen PWR has taken way longer than expected.
The public rightly insist on the safest designs possible. And those at least have been tried once (generally only once!). However, they take a long time.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Anyway, I don't want anyone to stop building renewables, but I don't want anyone to stop building nuclear either. We need every option.
(Even if nuclear is a safer bet.)
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
And again, nuclear can load follow /just fine/.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Sure, 80s French reactors can. As I understand it, modern PWRs can vary load but relatively slowly.
And in any case it is highly unlikely that we will be able to match *peak* demand with nuclear capacity.
You at least need significant intra-day storage.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis I do not understand your diagrams - which curve is the EPR on?
Realistically we'll have to build more EPRs. There isn't time to try more designs out.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Nuclear is faster at load following than everything but pumped hydro and (very dirty) gas peakers. It was even a design requirement for the german Konvoi type in the 70s and 80s.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Do you have figures for a modern PWR? Any modern PWR, and specifically EPR1000, since we're likely stuck with that?
In any case, you still need storage, because you won't be able to build capacity to peak demand.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
https://en.wikipedia.org/wiki/Load-following_power_plant#Nuclear_power_plants
For a grid of 100 GW peak demand, you either need
- 100 GW nuclear plants, or
- 100 GW storage output, plus (100 GW Γ storage loss factor) storage input (volatiles or whatever), plus additional transmission capabilities, or
- a combination of 60% nuclear plus, say 10% hydro, plus 30% volatiles
I'd say some variation on the last looks most plausible to me.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Well if we're ruling out long term storage (iron-air batteries and hydrogen), maybe 30-40% nuclear, 80% renewables (intentionally over 100%), and a fair bit of lithium storage?
Ultimately this is determined by how much we can build of each technology by the deadline (which ideally is 2030 or 2035). If we can scale up iron-air fast, that'd be great, but there's a lot of uncertainty there. But this also applies to nuclear: How much new nuclear we can build by 2035 is probably quite limited. Whether hydrogen can be significant on that timescale, and whether leaks can be managed, is another big question.
It's worth trying all the plausible technologies (i.e. other than biofuels and fossil+CCS).
PS "volatiles" *already* make up over 30% of the UK's generated kWh. π So I expect a higher figure.
IMHO the only thing that matters more than the ecological impact of the transition is the *speed* of the transition. Because that determines total carbon emitted. And it determines the carbon intensity of the rest of the transition.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Yes, but I'd like to add that we need to think about lifetimes.
Let's imagine having built all we need in 30 years, through sometimes extreme efforts.
Current solar panels, wind turbines, and batteries have a lifetime of (a bit generously) 30 years. So we'd have to immediately start again with the entire effort just to keep it up. I'm worrying that this might not be β¦ sustainable.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Fortunately we will have time to work on that. There is plenty of existing renewable plant coming to the end of its service life for us to work on recycling.
Also, hopefully longer term we move towards more rooftop solar rather than farm scale, though of course the amount of land used by solar is insignificant. Short term, farm scale is easy to install; long term, rooftop could be a requirement of construction.
Just as important, once we reach 95%+ renewable electricity, the ecological cost of building new stuff, whether recycled or not, drops dramatically.
Do we want to move towards more nuclear in the long run? Maybe so. On the other hand, the cost of renewables will continue to come down, and it's reasonable to expect the same is true of storage.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Also I expect demand to drop somewhat in the long term. Unfortunately the more serious degrowth measures will take decades, and the peak demand from heating and EVs means we will need a lot more electricity in 2040 than we have today.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis There is also the near-absolute worst case scenario where outdoor agriculture becomes untenable due to wildly inconsistent post-climate weather and the "land sharing vs land sparing" debate is forced down the land sparing route, i.e. if most food can only be grown in heated greenhouses, we'll need vast amounts of energy. In that scenario we may well need more nuclear. But if it's that bad that fast I have my doubts that civilisation can survive the transition; that sort of agriculture is very capital intensive as well as energy intensive, although it is higher yield and makes space for rewilding, and potentially could be our only option if things get really bad.
PS I am not endorsing climate controlled indoor agriculture here. I don't have a clear view on the land sharing vs land sparing thing. I know which side most "degrowth" people would take though.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
I think you do not realize how much of our population only exists because of Haber and Bosch.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis I'm not 100% sold on either view of agriculture, as I hint at above. Certainly organic farming goes too far - yields matter, because increased land use ultimately means more deforestation. However if yields are achieved through ecosystem destroying pollution and soil degradation that ultimately reduces yields, there's a problem.
Short term, hydrogen isn't a means of storing energy, it's a vital industrial ingredient, including for fertilisers, which mostly comes from fossil gas.
Cover crops could be introduced with a net increase in yields, while storing vast amounts of carbon, but generally cannot be afforded without a specific subsidy because our agricultural system is broken.
Not to mention the immense waste caused by biofuels. And by meat and dairy.
So there's lots to discuss there as well. (But not today)
@MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
It appears necessary (or inevitable) to shift our #culture towards #collectivism, which would entail radically different rates and modes of #consumption, and collection and use of #public funds. If large #states can't keep up, we need smaller ones that adapt and learn from each other. Material is abundant, we need to #distribute as it's needed. I agree with the urgency you express. Do you believe there is a path to avoid disaster?
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Sorry, but the term Β»degrowthΒ« is a red flag for me.
Sure, we are getting more efficient over time. That's why even Germany's emissions fell over the last two decades.
But cutting power that is actually needed means poverty, and that will immediately end support for long-term thinking as well as severely limit our technical options.
There are too many people for romantic visions of rural self-sufficiency.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis There are aspects of it that I disagree with.
More to the point there are implications that I disagree with. Clearly there is a need for growth in large parts of the world, and even amongst the poor in my own country.
On the other hand, there are many areas where demand reduction makes sense to speed up the transition. It is going to be many years before we have clean aviation, for instance. And a world with say 70% fewer cars in would be highly desirable for many good reasons.
Both the transition and the climate crisis will cause much suffering, requiring redistribution. Much of the work that needs to be done on efficiency can only be practically funded by the state.
And so you get degrowth: a reframing of politics and economics around a fair transition to sustainability.
Though perhaps the term isn't the ideal messaging.
I posted a relatively popular rant about how primitivism and degrowth are two very different things a while back. Can't find it right now.
Anyway, thanks for the discussion. I hope that you're right on a few things. π
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis It's also in opposition to the wider political picture of an alliance between fossil fuels, fascists, religion, the old right wing parties and so on, of course. π
That also makes it political.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
You seem to assume that only one reactor will be built at a time, and nothing learned. But that's not how you do it, and not how France already did it, obviously.
I have a little problem understanding how one can acknowledge the success of the Messmer plan and at the same time claim it unrepeatable.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Second generation reactor designs that would never be built today. Vulnerable to climate change because they were built on rivers. Also, Britain is not France.
Right now, renewables essentially build themselves. They do not require a state subsidy - the "contract for difference" level is set at roughly the wholesale price of electricity.
Whereas no nuclear is ever built without massive state involvement.
Not that that's bad. We need more state intervention in e.g. insulation. But it's slow. We can't afford to stop installing renewables now on the basis of a few reactors that may well be cancelled by a future government.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
At least Germany never had subsidies for commercial nuclear power.
On the other hand, Β»renewablesΒ« are still subsidized heavily, and there is much moaning right now because the build-out is slowing down, as the best places are taken.
And France has no /real/ problem with its riverside plants. Last year (much bemoaned) had 0.05% (one twentieth of a percent) curtailing for river temperatures.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis Farm scale solar, onshore and offshore (non-floating) wind cost approximately Β£50 per MWh in the last CfD auction. That's half the CFD agreed for Hinkley C.
Mature renewables are already cheaper than nuclear. By a factor of two, compared to first-of-a-kind over-budget new nuclear.
@matthewtoad43 @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis
Again, Β£50 per MWh is at current penetration levels of volatiles. This doesn't scale linearly.
See that you get to more-of-the-same-kind nuclear reactors. This does.
@Ardubal @MattMastodon @BrianSmith950 @Pampa @AlexisFR @Wirrvogel @Sodis What do you mean it doesn't scale linearly?
If you need to over-build by 3x, then it costs Β£150/MWh.
If you need to use Β£170/MWh storage for 10% of demand (plausible for hydrogen), you still get a very reasonable figure.
There's no obvious non-linearity here. Switching off renewables is trivial, unlike thermal plant.