"And what do you do then with baseload plants? By their very nature, they are supposed never to stop generating… But what if they are no longer needed for 6, 8 or 12 hours every day for 6 to 9 months of the year? Some of the baseload plants (like French nuclear) have some flexibility to vary their generation, but definitely not from 0 to 100% every day! And their economic model will be shot to pieces if they make no money whatsoever half, or even a quarter of the time."
=> the question here is on throttling power production when production outpaces demand - generally from renewables.
Currently, when electricity prices get too low, baseload (including Nuclear) throttle their production to not lose money, with older CFDs leaving little incentive for renewable producers to do so.
But Wind throttling is very easy, and with decent contracts, there is no reason for any turbine to run when market prices are negative. I'm not too sure about solar on this topic, though.
So we could imagine a world where Wind fully throttles before Nuclear when prices get extremely low.
For Wind producers, it wouldnt matter - producing at 0€/MWh or not is the same for them. While for nuclear, marginal costs of electricity are minimal anyways, and that would enable them not to have to go through a ramp-up phase where they lose money by not being at full capacity as soon as needed.
That leaves the business model in question - but extremely high renewable penetration and CO2 costs on a continental scale with few large scale storage options could lead to some marginal nuclear production (10-20% on contienent scale, basically what is planned now in Europe) being viable mid-term IF the nuclear industry gets their shit together.
Long-term though, if storage ever becomes competitive large scale within the next 25 years, nuclear might quickly become 100% uncompetitive.
Yes, this makes sense. I would actually expect that as demand learns to use surplus production when it's available and cheap, we could end up with a floor price created by such demand - activities that will be large enough in scale to generate enough demand at a low-ish price that prices don't go below that level anymore. That could indeed help nuclear stay competitive if, as you say, they get their shit together...
Thats a good point actually, but I wonder how this surplus demand will look like.
The time where we'll have long sequences of 5-10GW (on a european country scale - more like 50GW on continent scale) of free electricity is tomorrow, and the (10+B€) investments needed are today.
Hydrogen is the obvious idea here - but it probably wont be the only one.
I'm afraid the economics of these industries has not been created yet - with extremely fluctuating (~20% of the year) production, often in the middle of the day, sometimes at nights, sometimes with weeks on end of work or not, predictible only a few days ahead - what kind of worker will accept this?
Flexibility will be needed from workers, suppliers, deliverers, locals, and so, so much more. And the companies will need to actually pay very little for this electricity (and not have some flat taxes on it).
Fair point again. I suspect that a lot of the demand side stuff are things we can't imagine yet. I expect a lot of creativity and new things - a nd a lot of many different things at relatively small scale (just like solar is quite decentralized on the generation side)
There might be latitudes where lots of solar works. But not in Northern European countries like the UK. Wind also isn't the answer because of the variability that is uncorrelated to demand.
The conclusion I came to is that nuclear is the only answer for a low carbon energy system .
New offshore wind in the UK has a CF ~50% and the fleet as a whole is about 40%. The UK nuclear fleet is 58% and is largely unthrottleable. Those numbers seem to be rather similar at first glance, although they come at the problem from opposite sides I'd love to see the math behind your conclusion, do you have a spreadsheet posted somewhere?
Current UK fleet is very old and needs maintenance. Typical load factor for nuclear is ~90%. The link I posted goes through my logic and workings.
Yes, nuclear is not yet very good at load following which is why my mix was 120GW of nuclear plus 30GW of other dispatchable sources made up from hydro, waste incineration and gas. Some of that could be phased out for Gen IV nuclear SMRs such as from Natrium or Moltex that will be able to be more flexible.
Even in Northern latitudes solar will increasingly dominate day time production for more and more of the year, the trend will be less strong but will be the same. And strong wind penetration makes the amount to fill with flexible generation smaller in winter (lots of wind, especially offshore wind which has high capacity factors in winter), and makes the issue of surplus production (and incompatibility with nuclear) even bigger.
I agree that it is possible to build a rational, mostly decarbonated system with nuclear (if you have enough hydro); even if the cost and the non-finance-ability was not an issue (and it is), the unavoidably growing penetration of renewables makes it a moot question today.
In Vermont, our electric utility is installing PowerWalls and other large-ish battery storage in customer homes at no upfront cost (billed via our monthly bill). We can use them during grid outages to power the refrigerator and some lights. It comes with an agreement under which the utility can draw down power during peak usage times. The intent is to smooth out that "everyone just got home from work and is cooking dinner" evening spike.
So basically, the utility is building a virtual distributed peaker plant in residential areas. Since the power source is near the point of use, it has the added benefit of reducing line losses.
They also provide a "smart" car charger for free. It has time-of-use billing, so charging overnight comes at a subsidized rate, well below the cost of charging during the day and early evening (it's equivalent to roughly $1/gallon for a gas car), and includes an agreement that the charge rate can be throttled at peak times - with an override option, in case you NEED to charge at that time. Charging during a peak comes at a cost premium. It's still cheaper than gasoline, but a significant jump from the overnight cost, providing a solid incentive to charge later whenever possible.
I think the argument is somewhat self-defeating. Deeper renewable penetration can only work if that turtle can be spread out over the whole day's demand, which means enough storage to make time of generation more or less irrelevant. But then does it actually matter that your nuclear generates all day long if it can charge the same batteries (and utilise excess energy in exactly the same way you are saying it'd be with solar), while also reducing the amount of storage needed to get you through the night (or winter)?
One counterargument is that it'd be wasteful vs cheap solar on a $/kwh basis. However, this is not a good comparison, because you'd be comparing instantaneous costs of energy sold in a market with relatively low penetration, not aggregate costs of energy for the society. As an extreme example, if you switch off all fossils tomorrow, electricity price will be nearly infinite in the night while still being low during the day, making solar "cheap" in the instant sense but extremely expensive overall. Studies quantifying this "true" cost (that would include necessary transmission and storage, including land acquisition and NIMBY lawsuits for transmission etc) are probably out there, but I haven't seen any yet. By using instant energy prices instead you're effectively comparing (a lot of) fossils+renewables vs standalone nuclear, which does not support the argument that renewables leave no place for baseload. Renewables + fossils might not, but it's not the same, is it?
It's also important to note that you're being very US-centric here. In most of Europe, solar is barely (or inversely) correlated with demand for most of the year because of the need for heating. However, this is very seasonal, and baseload (nuclear or otherwise) is well positioned to respond to those week/month-scale changes.
- where there is a difference between solar+flexible and nuclear is that the demand curve is not flat, and the bits you need to manage in (demand-solar) are not the same as in (demand-baseload) - and probably easier and cheaper to manage (and less carbon-intensive)
- the US vs Europe point is true, but that's also where wind comes in, and plays a bigger role in winter (in that case, with a different profile to "fill in", where the gaps can be longer indeed.
In any case, the reality is that there will be a lot of solar, so the daily (demand-solar) is going to be nil/low a lot of the time in any case, and we have to build the new system around that hard unavoidable fact-in-the-making, unless we forbid new solar at some point.
> the bits you need to manage in (demand-solar) are not the same as in (demand-baseload)
I don't understand this point. Why do you think it's different? If anything, it seems that baseload makes it easier. With primarily solar, you get 8-ish hour of production a day that must feed *everything*, including aluminium smelters and whatnot, which means the rest of it is batteries. With nuclear, you want to absorb the daily production peak and use it more productively elsewhere, which means using it in exactly the same way through the rest of the day, just having that base level provided without batteries?
> that's also where wind comes in
Wind is much worse than solar because it often goes down for a week or two. It has this fractal variability, varying on all scales, unlike solar. To make sure you don't get blackouts with wind you need way more storage than with solar in California.
> the daily (demand-solar) is going to be nil/low a lot of the time in any case, and we have to build the new system around that hard unavoidable fact-in-the-making, unless we forbid new solar at some point
There is no need to forbid it, it would be unprofitable to build new solar in such circumstances without subsidies forcing utilities to buy the watts (in one form or another), regardless of how cheap it is. All solar produces at the same time, so the moment you saturate the market is the moment there is no point producing more.
" the bits you need to manage in (demand-solar) are not the same as in (demand-baseload)"
With nuclear (and any baseload) - you need on a daily basis, for several hours, to generate, reliably, the difference between your baseload production and your demand. That means, unless you ave a lot of hydro, a lot of gas-fired plants that run many hours each day.
With solar, you have just the morning and evening peaks to manage - much shorter
I agree that wind brings another dimension - "fractal variability" is a pretty way to describe it! but it's not impossible to manage - it's actually almost never down to zero (and also never at full power), it's easy to curtail, and it does produce at good times (in particular offshore wind)
As to solar, it will continue to be profitable "behind the meter" so will continue to be installed by households and small entreprises - individual projects will be small but cumulatively they will matter, unless they are actually forbidden. Utility-scale PV can be regulated by the absence of tariffs, or permitting/grid gates, but small scale solar cannot.
With solar, you still need power at night (even if less of it), which means batteries or fossils. So in a theoretical solar-first scenario you have to have enough power to eat the day peak (we're already here), enough batteries to cover morning/evening/night (the toughest part), and again enough power to charge those batteries (let's say x2-3 to daily load, not that big of a deal already). If you throw nuclear into the mix, you get power at night and more excess power during the day, which you can just store in the batteries in exactly the same way and discharge during the night, covering the shortfall of your baseload generation not covering the peaks. Then the balance between the number of batteries and nuclear is just an optimisation problem (taking into account transmission infra etc etc), and I'm not convinced that the optimal solution is zero nuclear.
Small scale relies on the same market forces, doesn't it? If you don't have a battery at home, residential solar is useless when electricity is free during the day, and if you do, you might just as well skip panels altogether and charge from the grid, it's free/negative anyway. This of course relies on utility providers being able to meter that correctly, but that's a solved problem. For example Octopus in the UK can charge with half an hour granularity, passing negative prices through.
Ultimately, I'm skeptical of nuclear because it's more expensive than the alternatives, and not financeable by the private sector. No country these days (other than China, maybe?) can push for such a momentous economic strategy as France did in the 70s with its first nuclear plan - it's not in th spirit of the times. One can regret it, but it will be hard to fight.
I agree completely that it's hard, I just think we should consider what'd be required for alternatives. No (western) country these days can build enough storage to go through a week or two of overcast, quiet weather (a regular occasion in Europe), or to build enough pylons across fields against local NIMBY opposition.
It's just hard either way, no two ways around it, we're just in the honeymoon phase of renewables, with low penetration and deep reliance on fossil fuels.
AREVA went bankrupt to a decent extent because of the nasty fights between AREVA and EDF in the 2000s - and its fights with Alstom or Bouygues who wanted to take it over, and its careless decision to try to build the Finalnd plant on its own when it had never done that (EDF had built plants, not Framatome)
Been trying to explain this dynamic, that is killing baseload coal, in South Australia just 40% RE wa enough for Alina to shutdown both of the last coalers, even with no price on carbon emissions. How can new build nuclear compete with RE when existing coal at probably a fifth of the costs overheads (including finance debt) can’t stay alive. But nuclear advocates just go into special pleading and concocting falsehoods about system costs of a 90% or 100% RE or 300% (including fuel switching to electricity in transport, buildings, industrial processes and land sector/farming) system.
Indeed. People are not often aware of the Australian examples, thanks for your input!
(Note that in France, EDF puts the price of power from refurbished and extended existing nuclear plants at 50-60 EUR/MWh - so even extending existing plants is acknowledged to be more expensive than new offshore wind)
You say: "Some of the base load plants (like French nuclear) have some flexibility to vary their generation, but definitely not from 0 to 100% every day! And their economic model will be shot to pieces if they make no money whatsoever half, or even a quarter of the time."
Ok, so far ... but French nuclear power platns don't have - and don't need - an 'economic model': the French utility company EdF is state-owned, no need to make profits, or even run economically. EdF is deeply indebted (some billion €), nobody cares, .and French taxpayers will pay off the debt some day .... (Please note that this is paritally sarcastic, but the debt of EdF is real!) G. from Germany
Well EDF has been hugely profitable during its first nuclear period, and a cash cow for the government, despite relatively low retail electricity prices (and it did make significant provisions for dismantling and waste management). It's only been since the failure to build Flamanville and the other EPRs that EDF's accounts are a mess
- This kind of gas plant being used sub-optimally, who's paying for this?
- what's the situation on the least sunny / no wind day of the year? i.e. the reality to be planned for.
- 80% or so of energy used in the economy is not electricity. Given the drive to reduce CO2 emissions, would nuclear, or any other baseload generation not have a place in this future, where energy uses are electrified?
Jessie Jenkins who has a bit of a nuclear power advocacy pedigree has modelled for this extensively for USA states. He thinks a case can be made but I’m yet to be convinced, his papers are extremely technical and possibly overly laden with econometric babble and probability representations that make the work hard to parse for someone just used to looking at 5 minute dispatch events in mixed models and seeing where the winners and losers are at any given suite of LCoE per technology.
The thing is, at say 90% RE you have significant overbuild in the system to dispatch that much RE, even via batteries and pumped hydro energy storage. 30% curtailment during the middle of the day and some nights is not uncommon in the most cost effective mixes to solve for 90% RE on the island grid of southwest WA which I modelled for extensively. I wish I could show some graphs. For any baseboard or slow ramping operator (coal, CCGT or nuclear) to try and come in and make money there, we’ll they are going to need an iron clad “take or pay” PPA from the government for a start, because no commercial entity is going to give them one for power all year long that they can buy much cheaper most of the time and even pick up for free or negative (since wind and solar earn certificates even when selling power at a negative price, though usually they also have fixed price pPAs and it’s the buyer under the PPA playing in the spot market to hedge and profit where they can).
And even with a fixed price, with an all you can take PPA like Hinkley ‘C’ has — even if they never finish the build or export the power(!!) — its not even necessarily going to help you that much through the winter doldrums because it’s not going to be large enough to dispatch peak demand maximum in winter or even half that and store the rest for later. So you’d need added capacity markets and structures like that to try and guaranty that supply. At which point, just more overbuild of RE to regions with complimentary wind and cloud patterns is so much cheaper than building reactors which won’t even be around until probably 20 years if it was legal to plan, build and commission one in Australia.
These re the hard facts for Australia, especially Western Australia which, despite being an island grid in the SW will possibly see 5 to 55 GW of additional RE just built to process and extract minerals without using fossil fuels in the supply chains. (I’m sceptical about shipping of liquid or compressed hydrogen as an energy carrier as a drop in replacement for fossil LNG shipping from WA and getting it out of the petro-state business any time before 2050).
Having tried to explain that even amortised baseload and load following coalers in Australia are struggling to compete with low cost wind and solar (even with no price on the extreme damages associated with GHG emissions) and super high end of costs nuclear power plants will need a full investment cycle, it’s just really hard to see nuclear ever getting a toe hold in Australia, but also Europe, outside of France and let’s see whether economics or politics decides that open question about the replacement of their fleet. USA, who knows, they often, like China these days just do things to show they can.
The problem with SMR is that, well a) you can’t by one for love or money to power a grid, and submarines and aircraft carrier nuclear reactors are a different class of rector with added costs and risks, the military can secure the fuel supply chain and waste movement me storage, no largely cover up any incidents at a sea by dumping the evidence bilge water, 3/4 of the surface of Earth is oceans. b) the idea that deployment in numbers is to misunderstand the kinds of exponentially growing numbers PV and wind turbines got deployed in to see linear LCOE reductions per doubling. And it as gives up scale, and scale is how thermal generation get their numbers down. Finally the complexity and levels of specialisation for Small Modular Reactor is still miles apart from PV cells and assembly of cells into solar panels and for that matter wind turbines, even with their sophistication today compared with 1980s turbines. The promise of SMRs are non-compelling that private sector energy investment expert and polymath academic Prof. Doyne Farmer says he just can’t see SMRs becoming commercial. He’s prepared to give you 100 to one odds that it never happens (before 2050 iirc the exact terms). He said it on David Robert Dr Volts podcast.
- There is a business case for power plants use very little but at times of peak demand: they are called "peakers" and they make money by selling their power at that time more expensively - high enough to be profitable overall.
- yes, there is a need for flexible MW to be available - you need a large fleet of hydro, storage and, for now, fossil-fuel fired flexible plants. But it's not because you have lots of such plants that you lots of emissions, if they are used only rarely. What we see in Germany is that flexible fossil fuel plants (gas and hard coal) are actually used less today with 50% renewables than when that share of electricity was provided by baseload plants (nuclear and lignite)
- that's a good question, but I suspect that the trend I'm outlining will hold true even if the electricity system grows. What might happen is that some large electricity-intensive users, in particular those that really need baseload (like aluminum plants, for instance) might be ready to procure baselaod electricity from dedicated power plants like nuclear. But I think it's low probability because (i) no private sector investor is going to underwrite nuclear construction or operations without sate guarantees, and (ii) you can get baseload more cheaply these days from other combinations of generation.
Thanks for the reply. To some degree this is counterintuitive, so kudos for documenting and explaining this to people. Will be interesting to see how this develops.
You are showing charts from a time close to the summer solstice when solar is at its peak, but demand from AC is still relatively low, and it is also a Sunday, the lowest demand day of the week. Your duck curve chart is also chosen from the lowest net demand of the year.
Those charts will look different in January, especially in Europe where demand peaks in winter when there is hardly any solar.
With solar and wind, back-up will always be needed, curtailment will always happen and massive overbuild is needed to correct seasonal variations. Efficient CCGT plants will not be the back-up, they take too long to ramp up and constant on/off operation creates high maintenance and shortens the life. The trend will be towards inefficient single cycle turbines or reciprocating engines. Natural gas will be difficult because it is just in time delivery, and who wants to own and maintain a whole gas supply train that is only needed intermittently.
Hydrogen is very inefficient (round trip efficiency of 35%) and it is very expensive to store, except in salt caverns that don't exist everywhere. The other storage methods, batteries, pumped hydro, compressed air etc are only good for intra-day variations in supply and demand, they do not scale to provide for seasonal or multi-year variations.
The issue with batteries is partly cost. California for example, would need about 500 GWh to provide power through the night with a solar powered grid (wind doesn't help because it may not be blowing). At today's prices that is $150 billion, replaced every 15 years. But that only takes care of the intra-day variations, on cloudy days there would not be enough juice to charge the batteries unless the solar were overbuilt by a factor of two. A nuclear baseload cuts the battery requirements significantly.
It is true that nuclear does not fit well with renewables, but the solution is to eliminate the renewables not the nuclear.
If the capacity is required for winter, we may see CCGTs mothballed throughout the rest of year and run hard and flat in combination with big batteries /PHES to handle the demand cycle fluctuations for the winter demand period. I expect deep ground (micro-geothermal, not hot rock geothermal) sourced heat storage for seasonal LD storage will tend to out compete fossil gas GTs or engines once methane leaks are accurately accounted for including well lifecycle emissions and GWP₂₀ or GWP₁₀ rather than GWP₁₀₀ indexes.
I meant to say _existing_ CCGTs since they’re probably already financed and paid off rather than building extra, new Reciprocating Engines or OCGT. But who knows where the economics and politics will settle.
Hi jaberwock, thanks for the substantive and relevant comment!
Here are a few additional comments on that:
"Those charts will look different in January, especially in Europe where demand peaks in winter when there is hardly any solar."
Yes, this is fully acknowledged - and I did mention that this would apply first in the summer, in some markets, but would spread more widely as solar keeps on growing.
The trend of more solar being installed is not going away, so this will become prevalent across a higher number of days, and more hours, as years go by. So this is something to prepare for, even if it's not urgent everywhere nor at all time.
"Efficient CCGT plants will not be the back-up, they take too long to ramp up and constant on/off operation creates high maintenance and shortens the life. The trend will be towards inefficient single cycle turbines or reciprocating engines. Natural gas will be difficult because it is just in time delivery, and who wants to own and maintain a whole gas supply train that is only needed intermittently."
Agreed - I used "gas-fired" as a shorthand for flexible fossil fuel plants - that may include, sometimes, diesel and other such fuels, and it will indeed lead to less effsicientuse of plants - but that's the business model of peakers - they generate few hours but are paid well at these times, and the actual efficiency is not what's driving the business case. What matters is the overall net generation (and emissions), and these can be low if the net number of hours remains low.
"Hydrogen is very inefficient (round trip efficiency of 35%) and it is very expensive to store, except in salt caverns that don't exist everywhere. The other storage methods, batteries, pumped hydro, compressed air etc are only good for intra-day variations in supply and demand, they do not scale to provide for seasonal or multi-year variations."
All agreed - but the point noted here is that the duck curve is a daily phenomenon and that is something that existing storage technologies (including hydro) can manage well. The wider seasonal variations are a separate topic - definitely an important one but not the one I was touching upon here.
"It is true that nuclear does not fit well with renewables, but the solution is to eliminate the renewables not the nuclear."
That would indeed be a solution (and let's be clear, I acknowledge that a nuclear-dominated system could work: France did it well and proved it was a generally efficient way to run a power system), but it's just not going to happen: that's the reality that the po-nuclear lobby needs t acknowledge: renewables are not going away, they are growing massively each year, and they will take up more and more of the system. In *that* context, nuclear makes no sense, even if in isolation it would have worked. The point is that nothing is done in isolation in the energy system (and that's a point that many people forget - for instance when they ask when happens when there is no wind - nobody is suggesting to build a system based only on wind).
Fossil gas peaker generation (OCGTs & reciprocating engines) is already used on an intermittent basis. As a price setter, peaker GTs are always highest to bid and usually last to be dispatched in the merit order. There’s nothing new about burning a whole lot more gas for two weeks straight in winter on the SWIS island grid in Southwest Western Australia than in spring or autumn. Nothing new at all about differences in consumption over a day, week or month.
So how does that work according to your alleged “just in time” delivery method. Well, we are not talking about drop shipping here, nor the manufacture of consumer goods. There’s a big fat pipe connecting the offshore gas fields of northern WA with the population centre in the SW. And they can maintain that pipe at a range of pressures. In fact with maximum packing they can store about of weeks of a typical supply demand in the pipe alone. So ups and downs demand can be balanced out in-pipe and with storage facilities and by changing the mix of flow onshore and offshore for exports. While the market is there for the gas they will maintain
Also the the supply and sell it down south. There’s a fix price arrangement enforced by the government under the former Labor Govt (WA inc) so the corporates have to supply it and at a fixed price, sometimes (like atm) that is to the benefit of consumers at other times that’s been to the benefit of the fossil fuel companies. Either way it’s a hedge for both parties and the cost of taking a nationally owned resource for next to nothing no flogging it in SE Asia.
I'd like to comment on this paragraph
"And what do you do then with baseload plants? By their very nature, they are supposed never to stop generating… But what if they are no longer needed for 6, 8 or 12 hours every day for 6 to 9 months of the year? Some of the baseload plants (like French nuclear) have some flexibility to vary their generation, but definitely not from 0 to 100% every day! And their economic model will be shot to pieces if they make no money whatsoever half, or even a quarter of the time."
=> the question here is on throttling power production when production outpaces demand - generally from renewables.
Currently, when electricity prices get too low, baseload (including Nuclear) throttle their production to not lose money, with older CFDs leaving little incentive for renewable producers to do so.
But Wind throttling is very easy, and with decent contracts, there is no reason for any turbine to run when market prices are negative. I'm not too sure about solar on this topic, though.
So we could imagine a world where Wind fully throttles before Nuclear when prices get extremely low.
For Wind producers, it wouldnt matter - producing at 0€/MWh or not is the same for them. While for nuclear, marginal costs of electricity are minimal anyways, and that would enable them not to have to go through a ramp-up phase where they lose money by not being at full capacity as soon as needed.
That leaves the business model in question - but extremely high renewable penetration and CO2 costs on a continental scale with few large scale storage options could lead to some marginal nuclear production (10-20% on contienent scale, basically what is planned now in Europe) being viable mid-term IF the nuclear industry gets their shit together.
Long-term though, if storage ever becomes competitive large scale within the next 25 years, nuclear might quickly become 100% uncompetitive.
Any thoughts on this?
Yes, this makes sense. I would actually expect that as demand learns to use surplus production when it's available and cheap, we could end up with a floor price created by such demand - activities that will be large enough in scale to generate enough demand at a low-ish price that prices don't go below that level anymore. That could indeed help nuclear stay competitive if, as you say, they get their shit together...
Thats a good point actually, but I wonder how this surplus demand will look like.
The time where we'll have long sequences of 5-10GW (on a european country scale - more like 50GW on continent scale) of free electricity is tomorrow, and the (10+B€) investments needed are today.
Hydrogen is the obvious idea here - but it probably wont be the only one.
I'm afraid the economics of these industries has not been created yet - with extremely fluctuating (~20% of the year) production, often in the middle of the day, sometimes at nights, sometimes with weeks on end of work or not, predictible only a few days ahead - what kind of worker will accept this?
Flexibility will be needed from workers, suppliers, deliverers, locals, and so, so much more. And the companies will need to actually pay very little for this electricity (and not have some flat taxes on it).
Best regards.
Fair point again. I suspect that a lot of the demand side stuff are things we can't imagine yet. I expect a lot of creativity and new things - a nd a lot of many different things at relatively small scale (just like solar is quite decentralized on the generation side)
Strong article and enjoyable to read as well. Congratulations. Diana, KfW IPEX-Bank GmbH
There might be latitudes where lots of solar works. But not in Northern European countries like the UK. Wind also isn't the answer because of the variability that is uncorrelated to demand.
The conclusion I came to is that nuclear is the only answer for a low carbon energy system .
https://open.substack.com/pub/davidturver/p/nuclear-power-everywhere-all-at-once?utm_source=direct&r=nhgn1&utm_campaign=post&utm_medium=web
New offshore wind in the UK has a CF ~50% and the fleet as a whole is about 40%. The UK nuclear fleet is 58% and is largely unthrottleable. Those numbers seem to be rather similar at first glance, although they come at the problem from opposite sides I'd love to see the math behind your conclusion, do you have a spreadsheet posted somewhere?
Current UK fleet is very old and needs maintenance. Typical load factor for nuclear is ~90%. The link I posted goes through my logic and workings.
Yes, nuclear is not yet very good at load following which is why my mix was 120GW of nuclear plus 30GW of other dispatchable sources made up from hydro, waste incineration and gas. Some of that could be phased out for Gen IV nuclear SMRs such as from Natrium or Moltex that will be able to be more flexible.
"The link I posted goes through my logic and workings." - not in detail though. Do you have the nitty-gritty details?
Even in Northern latitudes solar will increasingly dominate day time production for more and more of the year, the trend will be less strong but will be the same. And strong wind penetration makes the amount to fill with flexible generation smaller in winter (lots of wind, especially offshore wind which has high capacity factors in winter), and makes the issue of surplus production (and incompatibility with nuclear) even bigger.
I agree that it is possible to build a rational, mostly decarbonated system with nuclear (if you have enough hydro); even if the cost and the non-finance-ability was not an issue (and it is), the unavoidably growing penetration of renewables makes it a moot question today.
In Vermont, our electric utility is installing PowerWalls and other large-ish battery storage in customer homes at no upfront cost (billed via our monthly bill). We can use them during grid outages to power the refrigerator and some lights. It comes with an agreement under which the utility can draw down power during peak usage times. The intent is to smooth out that "everyone just got home from work and is cooking dinner" evening spike.
So basically, the utility is building a virtual distributed peaker plant in residential areas. Since the power source is near the point of use, it has the added benefit of reducing line losses.
They also provide a "smart" car charger for free. It has time-of-use billing, so charging overnight comes at a subsidized rate, well below the cost of charging during the day and early evening (it's equivalent to roughly $1/gallon for a gas car), and includes an agreement that the charge rate can be throttled at peak times - with an override option, in case you NEED to charge at that time. Charging during a peak comes at a cost premium. It's still cheaper than gasoline, but a significant jump from the overnight cost, providing a solid incentive to charge later whenever possible.
I think the argument is somewhat self-defeating. Deeper renewable penetration can only work if that turtle can be spread out over the whole day's demand, which means enough storage to make time of generation more or less irrelevant. But then does it actually matter that your nuclear generates all day long if it can charge the same batteries (and utilise excess energy in exactly the same way you are saying it'd be with solar), while also reducing the amount of storage needed to get you through the night (or winter)?
One counterargument is that it'd be wasteful vs cheap solar on a $/kwh basis. However, this is not a good comparison, because you'd be comparing instantaneous costs of energy sold in a market with relatively low penetration, not aggregate costs of energy for the society. As an extreme example, if you switch off all fossils tomorrow, electricity price will be nearly infinite in the night while still being low during the day, making solar "cheap" in the instant sense but extremely expensive overall. Studies quantifying this "true" cost (that would include necessary transmission and storage, including land acquisition and NIMBY lawsuits for transmission etc) are probably out there, but I haven't seen any yet. By using instant energy prices instead you're effectively comparing (a lot of) fossils+renewables vs standalone nuclear, which does not support the argument that renewables leave no place for baseload. Renewables + fossils might not, but it's not the same, is it?
It's also important to note that you're being very US-centric here. In most of Europe, solar is barely (or inversely) correlated with demand for most of the year because of the need for heating. However, this is very seasonal, and baseload (nuclear or otherwise) is well positioned to respond to those week/month-scale changes.
Interesting points, thanks
- where there is a difference between solar+flexible and nuclear is that the demand curve is not flat, and the bits you need to manage in (demand-solar) are not the same as in (demand-baseload) - and probably easier and cheaper to manage (and less carbon-intensive)
- the US vs Europe point is true, but that's also where wind comes in, and plays a bigger role in winter (in that case, with a different profile to "fill in", where the gaps can be longer indeed.
In any case, the reality is that there will be a lot of solar, so the daily (demand-solar) is going to be nil/low a lot of the time in any case, and we have to build the new system around that hard unavoidable fact-in-the-making, unless we forbid new solar at some point.
> the bits you need to manage in (demand-solar) are not the same as in (demand-baseload)
I don't understand this point. Why do you think it's different? If anything, it seems that baseload makes it easier. With primarily solar, you get 8-ish hour of production a day that must feed *everything*, including aluminium smelters and whatnot, which means the rest of it is batteries. With nuclear, you want to absorb the daily production peak and use it more productively elsewhere, which means using it in exactly the same way through the rest of the day, just having that base level provided without batteries?
> that's also where wind comes in
Wind is much worse than solar because it often goes down for a week or two. It has this fractal variability, varying on all scales, unlike solar. To make sure you don't get blackouts with wind you need way more storage than with solar in California.
> the daily (demand-solar) is going to be nil/low a lot of the time in any case, and we have to build the new system around that hard unavoidable fact-in-the-making, unless we forbid new solar at some point
There is no need to forbid it, it would be unprofitable to build new solar in such circumstances without subsidies forcing utilities to buy the watts (in one form or another), regardless of how cheap it is. All solar produces at the same time, so the moment you saturate the market is the moment there is no point producing more.
" the bits you need to manage in (demand-solar) are not the same as in (demand-baseload)"
With nuclear (and any baseload) - you need on a daily basis, for several hours, to generate, reliably, the difference between your baseload production and your demand. That means, unless you ave a lot of hydro, a lot of gas-fired plants that run many hours each day.
With solar, you have just the morning and evening peaks to manage - much shorter
I agree that wind brings another dimension - "fractal variability" is a pretty way to describe it! but it's not impossible to manage - it's actually almost never down to zero (and also never at full power), it's easy to curtail, and it does produce at good times (in particular offshore wind)
As to solar, it will continue to be profitable "behind the meter" so will continue to be installed by households and small entreprises - individual projects will be small but cumulatively they will matter, unless they are actually forbidden. Utility-scale PV can be regulated by the absence of tariffs, or permitting/grid gates, but small scale solar cannot.
With solar, you still need power at night (even if less of it), which means batteries or fossils. So in a theoretical solar-first scenario you have to have enough power to eat the day peak (we're already here), enough batteries to cover morning/evening/night (the toughest part), and again enough power to charge those batteries (let's say x2-3 to daily load, not that big of a deal already). If you throw nuclear into the mix, you get power at night and more excess power during the day, which you can just store in the batteries in exactly the same way and discharge during the night, covering the shortfall of your baseload generation not covering the peaks. Then the balance between the number of batteries and nuclear is just an optimisation problem (taking into account transmission infra etc etc), and I'm not convinced that the optimal solution is zero nuclear.
Small scale relies on the same market forces, doesn't it? If you don't have a battery at home, residential solar is useless when electricity is free during the day, and if you do, you might just as well skip panels altogether and charge from the grid, it's free/negative anyway. This of course relies on utility providers being able to meter that correctly, but that's a solved problem. For example Octopus in the UK can charge with half an hour granularity, passing negative prices through.
You make a convincing case!
Ultimately, I'm skeptical of nuclear because it's more expensive than the alternatives, and not financeable by the private sector. No country these days (other than China, maybe?) can push for such a momentous economic strategy as France did in the 70s with its first nuclear plan - it's not in th spirit of the times. One can regret it, but it will be hard to fight.
I agree completely that it's hard, I just think we should consider what'd be required for alternatives. No (western) country these days can build enough storage to go through a week or two of overcast, quiet weather (a regular occasion in Europe), or to build enough pylons across fields against local NIMBY opposition.
It's just hard either way, no two ways around it, we're just in the honeymoon phase of renewables, with low penetration and deep reliance on fossil fuels.
... and the urged take-over of next-to-bankriupt AREVA also did not contribute well to EdF's balance sheet, I would guess.
AREVA went bankrupt to a decent extent because of the nasty fights between AREVA and EDF in the 2000s - and its fights with Alstom or Bouygues who wanted to take it over, and its careless decision to try to build the Finalnd plant on its own when it had never done that (EDF had built plants, not Framatome)
SOE - ? what does it mean,?
Well, EdF was for the most part owned by the French state, it was only a comparatively small percentage of private persons still holding shares ... at last 2% ... (https://www.barrons.com/news/shares-of-renationalised-french-power-firm-edf-delisted-fddf5dfe)
SOE = State-owned enterprise. In English it's a dirty word :)
Been trying to explain this dynamic, that is killing baseload coal, in South Australia just 40% RE wa enough for Alina to shutdown both of the last coalers, even with no price on carbon emissions. How can new build nuclear compete with RE when existing coal at probably a fifth of the costs overheads (including finance debt) can’t stay alive. But nuclear advocates just go into special pleading and concocting falsehoods about system costs of a 90% or 100% RE or 300% (including fuel switching to electricity in transport, buildings, industrial processes and land sector/farming) system.
Indeed. People are not often aware of the Australian examples, thanks for your input!
(Note that in France, EDF puts the price of power from refurbished and extended existing nuclear plants at 50-60 EUR/MWh - so even extending existing plants is acknowledged to be more expensive than new offshore wind)
Trying for at least five years since Alina close Northern no Playford down in SA in 2015 that is!
You say: "Some of the base load plants (like French nuclear) have some flexibility to vary their generation, but definitely not from 0 to 100% every day! And their economic model will be shot to pieces if they make no money whatsoever half, or even a quarter of the time."
Ok, so far ... but French nuclear power platns don't have - and don't need - an 'economic model': the French utility company EdF is state-owned, no need to make profits, or even run economically. EdF is deeply indebted (some billion €), nobody cares, .and French taxpayers will pay off the debt some day .... (Please note that this is paritally sarcastic, but the debt of EdF is real!) G. from Germany
Well EDF is a SOE today because it just got renationalised because the privatised EDF went bankrupt last year, again.
Well EDF has been hugely profitable during its first nuclear period, and a cash cow for the government, despite relatively low retail electricity prices (and it did make significant provisions for dismantling and waste management). It's only been since the failure to build Flamanville and the other EPRs that EDF's accounts are a mess
I'm a layman, but would like to know:
- This kind of gas plant being used sub-optimally, who's paying for this?
- what's the situation on the least sunny / no wind day of the year? i.e. the reality to be planned for.
- 80% or so of energy used in the economy is not electricity. Given the drive to reduce CO2 emissions, would nuclear, or any other baseload generation not have a place in this future, where energy uses are electrified?
Jessie Jenkins who has a bit of a nuclear power advocacy pedigree has modelled for this extensively for USA states. He thinks a case can be made but I’m yet to be convinced, his papers are extremely technical and possibly overly laden with econometric babble and probability representations that make the work hard to parse for someone just used to looking at 5 minute dispatch events in mixed models and seeing where the winners and losers are at any given suite of LCoE per technology.
The thing is, at say 90% RE you have significant overbuild in the system to dispatch that much RE, even via batteries and pumped hydro energy storage. 30% curtailment during the middle of the day and some nights is not uncommon in the most cost effective mixes to solve for 90% RE on the island grid of southwest WA which I modelled for extensively. I wish I could show some graphs. For any baseboard or slow ramping operator (coal, CCGT or nuclear) to try and come in and make money there, we’ll they are going to need an iron clad “take or pay” PPA from the government for a start, because no commercial entity is going to give them one for power all year long that they can buy much cheaper most of the time and even pick up for free or negative (since wind and solar earn certificates even when selling power at a negative price, though usually they also have fixed price pPAs and it’s the buyer under the PPA playing in the spot market to hedge and profit where they can).
And even with a fixed price, with an all you can take PPA like Hinkley ‘C’ has — even if they never finish the build or export the power(!!) — its not even necessarily going to help you that much through the winter doldrums because it’s not going to be large enough to dispatch peak demand maximum in winter or even half that and store the rest for later. So you’d need added capacity markets and structures like that to try and guaranty that supply. At which point, just more overbuild of RE to regions with complimentary wind and cloud patterns is so much cheaper than building reactors which won’t even be around until probably 20 years if it was legal to plan, build and commission one in Australia.
These re the hard facts for Australia, especially Western Australia which, despite being an island grid in the SW will possibly see 5 to 55 GW of additional RE just built to process and extract minerals without using fossil fuels in the supply chains. (I’m sceptical about shipping of liquid or compressed hydrogen as an energy carrier as a drop in replacement for fossil LNG shipping from WA and getting it out of the petro-state business any time before 2050).
Having tried to explain that even amortised baseload and load following coalers in Australia are struggling to compete with low cost wind and solar (even with no price on the extreme damages associated with GHG emissions) and super high end of costs nuclear power plants will need a full investment cycle, it’s just really hard to see nuclear ever getting a toe hold in Australia, but also Europe, outside of France and let’s see whether economics or politics decides that open question about the replacement of their fleet. USA, who knows, they often, like China these days just do things to show they can.
The problem with SMR is that, well a) you can’t by one for love or money to power a grid, and submarines and aircraft carrier nuclear reactors are a different class of rector with added costs and risks, the military can secure the fuel supply chain and waste movement me storage, no largely cover up any incidents at a sea by dumping the evidence bilge water, 3/4 of the surface of Earth is oceans. b) the idea that deployment in numbers is to misunderstand the kinds of exponentially growing numbers PV and wind turbines got deployed in to see linear LCOE reductions per doubling. And it as gives up scale, and scale is how thermal generation get their numbers down. Finally the complexity and levels of specialisation for Small Modular Reactor is still miles apart from PV cells and assembly of cells into solar panels and for that matter wind turbines, even with their sophistication today compared with 1980s turbines. The promise of SMRs are non-compelling that private sector energy investment expert and polymath academic Prof. Doyne Farmer says he just can’t see SMRs becoming commercial. He’s prepared to give you 100 to one odds that it never happens (before 2050 iirc the exact terms). He said it on David Robert Dr Volts podcast.
- There is a business case for power plants use very little but at times of peak demand: they are called "peakers" and they make money by selling their power at that time more expensively - high enough to be profitable overall.
- yes, there is a need for flexible MW to be available - you need a large fleet of hydro, storage and, for now, fossil-fuel fired flexible plants. But it's not because you have lots of such plants that you lots of emissions, if they are used only rarely. What we see in Germany is that flexible fossil fuel plants (gas and hard coal) are actually used less today with 50% renewables than when that share of electricity was provided by baseload plants (nuclear and lignite)
- that's a good question, but I suspect that the trend I'm outlining will hold true even if the electricity system grows. What might happen is that some large electricity-intensive users, in particular those that really need baseload (like aluminum plants, for instance) might be ready to procure baselaod electricity from dedicated power plants like nuclear. But I think it's low probability because (i) no private sector investor is going to underwrite nuclear construction or operations without sate guarantees, and (ii) you can get baseload more cheaply these days from other combinations of generation.
Thanks for the reply. To some degree this is counterintuitive, so kudos for documenting and explaining this to people. Will be interesting to see how this develops.
You are showing charts from a time close to the summer solstice when solar is at its peak, but demand from AC is still relatively low, and it is also a Sunday, the lowest demand day of the week. Your duck curve chart is also chosen from the lowest net demand of the year.
Those charts will look different in January, especially in Europe where demand peaks in winter when there is hardly any solar.
With solar and wind, back-up will always be needed, curtailment will always happen and massive overbuild is needed to correct seasonal variations. Efficient CCGT plants will not be the back-up, they take too long to ramp up and constant on/off operation creates high maintenance and shortens the life. The trend will be towards inefficient single cycle turbines or reciprocating engines. Natural gas will be difficult because it is just in time delivery, and who wants to own and maintain a whole gas supply train that is only needed intermittently.
Hydrogen is very inefficient (round trip efficiency of 35%) and it is very expensive to store, except in salt caverns that don't exist everywhere. The other storage methods, batteries, pumped hydro, compressed air etc are only good for intra-day variations in supply and demand, they do not scale to provide for seasonal or multi-year variations.
The issue with batteries is partly cost. California for example, would need about 500 GWh to provide power through the night with a solar powered grid (wind doesn't help because it may not be blowing). At today's prices that is $150 billion, replaced every 15 years. But that only takes care of the intra-day variations, on cloudy days there would not be enough juice to charge the batteries unless the solar were overbuilt by a factor of two. A nuclear baseload cuts the battery requirements significantly.
It is true that nuclear does not fit well with renewables, but the solution is to eliminate the renewables not the nuclear.
If the capacity is required for winter, we may see CCGTs mothballed throughout the rest of year and run hard and flat in combination with big batteries /PHES to handle the demand cycle fluctuations for the winter demand period. I expect deep ground (micro-geothermal, not hot rock geothermal) sourced heat storage for seasonal LD storage will tend to out compete fossil gas GTs or engines once methane leaks are accurately accounted for including well lifecycle emissions and GWP₂₀ or GWP₁₀ rather than GWP₁₀₀ indexes.
I meant to say _existing_ CCGTs since they’re probably already financed and paid off rather than building extra, new Reciprocating Engines or OCGT. But who knows where the economics and politics will settle.
Hi jaberwock, thanks for the substantive and relevant comment!
Here are a few additional comments on that:
"Those charts will look different in January, especially in Europe where demand peaks in winter when there is hardly any solar."
Yes, this is fully acknowledged - and I did mention that this would apply first in the summer, in some markets, but would spread more widely as solar keeps on growing.
The trend of more solar being installed is not going away, so this will become prevalent across a higher number of days, and more hours, as years go by. So this is something to prepare for, even if it's not urgent everywhere nor at all time.
"Efficient CCGT plants will not be the back-up, they take too long to ramp up and constant on/off operation creates high maintenance and shortens the life. The trend will be towards inefficient single cycle turbines or reciprocating engines. Natural gas will be difficult because it is just in time delivery, and who wants to own and maintain a whole gas supply train that is only needed intermittently."
Agreed - I used "gas-fired" as a shorthand for flexible fossil fuel plants - that may include, sometimes, diesel and other such fuels, and it will indeed lead to less effsicientuse of plants - but that's the business model of peakers - they generate few hours but are paid well at these times, and the actual efficiency is not what's driving the business case. What matters is the overall net generation (and emissions), and these can be low if the net number of hours remains low.
"Hydrogen is very inefficient (round trip efficiency of 35%) and it is very expensive to store, except in salt caverns that don't exist everywhere. The other storage methods, batteries, pumped hydro, compressed air etc are only good for intra-day variations in supply and demand, they do not scale to provide for seasonal or multi-year variations."
All agreed - but the point noted here is that the duck curve is a daily phenomenon and that is something that existing storage technologies (including hydro) can manage well. The wider seasonal variations are a separate topic - definitely an important one but not the one I was touching upon here.
"It is true that nuclear does not fit well with renewables, but the solution is to eliminate the renewables not the nuclear."
That would indeed be a solution (and let's be clear, I acknowledge that a nuclear-dominated system could work: France did it well and proved it was a generally efficient way to run a power system), but it's just not going to happen: that's the reality that the po-nuclear lobby needs t acknowledge: renewables are not going away, they are growing massively each year, and they will take up more and more of the system. In *that* context, nuclear makes no sense, even if in isolation it would have worked. The point is that nothing is done in isolation in the energy system (and that's a point that many people forget - for instance when they ask when happens when there is no wind - nobody is suggesting to build a system based only on wind).
Thanks in any case for the useful contribution!
@Jabberwock,
Fossil gas peaker generation (OCGTs & reciprocating engines) is already used on an intermittent basis. As a price setter, peaker GTs are always highest to bid and usually last to be dispatched in the merit order. There’s nothing new about burning a whole lot more gas for two weeks straight in winter on the SWIS island grid in Southwest Western Australia than in spring or autumn. Nothing new at all about differences in consumption over a day, week or month.
So how does that work according to your alleged “just in time” delivery method. Well, we are not talking about drop shipping here, nor the manufacture of consumer goods. There’s a big fat pipe connecting the offshore gas fields of northern WA with the population centre in the SW. And they can maintain that pipe at a range of pressures. In fact with maximum packing they can store about of weeks of a typical supply demand in the pipe alone. So ups and downs demand can be balanced out in-pipe and with storage facilities and by changing the mix of flow onshore and offshore for exports. While the market is there for the gas they will maintain
Also the the supply and sell it down south. There’s a fix price arrangement enforced by the government under the former Labor Govt (WA inc) so the corporates have to supply it and at a fixed price, sometimes (like atm) that is to the benefit of consumers at other times that’s been to the benefit of the fossil fuel companies. Either way it’s a hedge for both parties and the cost of taking a nationally owned resource for next to nothing no flogging it in SE Asia.