Also: Renewables have downsides, but they are vastly cheaper and more proven.
There is no reason to assume that the downsides of various other techs are in any way more manageable. (And ironically some of the solutions proposed for the downsides of nuclear are also what you need for renewables, i.e. storage to maximize use of expensive infrastructure with low opex.)
> And ironically some of the solutions proposed for the downsides of nuclear are also what you need for renewables, i.e. storage to maximize use of expensive infrastructure with low opex.
It's exhausting to see this claim see the light so often, despite being debunked so frequently.
Nuclear doesn't require storage.
Some people claim that economies could be made with storage because then you wouldn't need to build production equivalent to 100% of your peak consumption.
The dishonest discourse happens when renewables proponent claim that this small potential optimization means nuclear needs storage just as much as renewables do. Actually, losing your power source is not equivalent to shaving a few %s of budget.
This idea also completely ignores the fact that power grids don't optimize for efficiency, but for stability. We want redundant production, and the ability to move as many cursors as possible on the grid, in order to balance for issues. The ability to ramp up a power plant isn't just useful to produce peak load, it also helps mitigating e.g. losing a power line or a power transformer.
Assume a capacity factor of 50% then to handle peak loads? Now the nuclear costs $240-440/MWh. That is ridiculous costs, worse than Europe during the last winters Russian war induced gas crisis.
The report you quote already cites load factor around 90% for new builds, a 50% load factor wouldn't double the costs. That being said, 90% load factor for a grid with a high share of nuclear is probably extremely optimistic.
The reason such high capacity factors can be reached in countries that have a low nuclear share is that nuclear has an extremely low marginal cost, and is always picked over plants that require fuel.
True, the fixed costs are $20-35/MWh. Deduct that from the figure before doubling. Not that it matters.
Running a pure nuclear grid will never get 90% capacity factor. That relies on only taking the base load and offloading the actual hard part to other generators. Exactly what nuclear proponents like to say will be impossible for renewables.
> That relies on only taking the base load and offloading the actual hard part to other generators. Exactly what nuclear proponents like to say will be impossible for renewables.
It's certainly not impossible, since that's what we do currently. The reason we would like to stop doing it in the future is co2 emissions, not a feasibility barrier.
Now my point was that we don't have experience of massive storage. And in the absence of storage, nuclear costs go up, while renewables output goes down. One is painful but manageable, we don't have a plan to handle the other.
Personally, I wish we spent a bit less subsidies on renewable production, and a bit more on grid-sized storage, so we can have an answer on costs. Without this, discussions on storage-enabled grids are conjectures at best.
For the benefit of the bystander: this person actually has no idea what energy seen planning looks like in real life. Economic optimization is absolutely at the core of it. Energy System Models (Essen) are economic optimization models. Depending on country and climate, the factor of the sibling comment of 50% is absolutely realistic.
Also these details don't really matter: Storage is a viable solution to the problem that Renewables are not dispatch able. The only argument against storage could be economic: That the inefficiencies and cost of storage render nuclear cheaper after all.
Not sure whether you understand the difference between the prospective world of public analysts, and actually running a power grid. I know there can be a divide between the two, and some self-agrandizement on each side. Picking reliability over efficiency is the sound economic choice.
Please note that my comment is not about the viability of storage for renewables.
I semi-regularly talk to people that plan the European power grid, yes. At the core of extension and development studies is still an optimal power flow, which is an economic optimization. Stability (which has many meanings here) is usually studied as a second step.
Security of Supply is yet another issue.
Anyway, if you can use storage to lower you nuclear costs by 5% overall, would it not be used? If your comment is not about viability of large scale storage, then what is it about? Storage is dispatchable, and an economically optimal 100% renewables grid will have a peak capacity far above actual peak demand, meaning it's typically curtailed (or you run electrolysers which again can beade dispatchable and grid-forming as loads) which again means you have plenty of ability to react.
Resilience research tends to favor decentralized solutions as well. Look at how Puerto Rico is being rebuilt.
> I semi-regularly talk to people that plan the European power grid, yes.
Hard to know which group of people you talk to. This kind of work happens at many different levels, for many different reasons. TSO investment decisions are not made by the same people than power production investment decisions. There is some coordination, but no centralized decision-making.
To the best of my knowledge of at least one major European TSO, investment decisions are not taken at european level. And while there is strong european coordination in grid management, it is still cooperation and not an unified decision process. Any europe-level investment advice would have to be evaluated and selected by the TSO to become effective. Also the further you go from the field, the more likely studies are to consider spherical cows. Still useful, but not the full picture.
> Anyway, if you can use storage to lower you nuclear costs by 5% overall, would it not be used?
Of course it would, and we do use reversible dams to optimize costs. My point is that:
1) that's a whole-production optimization, and the trigger for that optimization is increasingly renewables rather than optimizing for nuclear production stability
2) the difference between paying 5% more and having to cut consumers from the grid is massive. for any TSO trying to save money is a goal, but curtailing consumption is an absolute failure criterion, second only to damaging the grid itself.
> Resilience research tends to favor decentralized solutions as well.
I might be biased by my personal experience, but when it comes to a power grid, planning ahead of time is much more valuable than decentralization. There is a difference between avoiding concentration of material, something which can be handled with central oversignt, and decentralization, which creates a coordination cost and sometimes loss of information (which is the case when small renewable production is connected to the distribution network rather than the transport network).
The TSOs coordinate in ENTSOE, they are not responsible for actual energy production. But they are responsible for many aspects of system stability, and ENTSOE also coordinates security of supply studies.
How to make sure that everything that is needed in order to have sufficient production capacity in all scenarios is also built is not in the responsibility of TSOs. Of course when we consider how to develop flexibility and system service markets we are exactly talking about making sure that everything that is needed _is_ built. Not through centralized planning but by making sure we have a market where we pay for people to provide what is needed.
The big questions, like energy only vs capacity markets, are directly about making sure the necessary investments are made, no matter what technology options are backing them up. You don't need central planning, but you need ESM studies to guide your market designs and long term political decisions (i.e. do we need a hydrogen grid).
And the fact that right now we don't have a market (or other incentives/regulations) for virtual inertia is a real problem worrying TSOs (much more so than the hypothetical issue of under-supply in 10-20 years that you raise for which the basic organisational mechanisms are in place).
> 2) the difference between paying 5% more and having to cut consumers from the grid is massive. for any TSO trying to save money is a goal, but curtailing consumption is an absolute failure criterion, second only to damaging the grid itself.
Of course, but what is your point? That renewables require massive storage to ensure supply at all time? Yes. That's obvious.
But, as every study and common sense shows, it turns out massive storage is also helpful for a nuclear grid, especially once we get into electrifying the heat sector (an important point you have not acknowledged at all).
Finally security of supply studies also assume that conventional generators sometimes fail for unpredictable reasons. In Texas it wasn't the renewables, it was the gas system freezing over that almost fucked up the grid.
I still don't get what your initial complaint was about. The point I made was pretty explicitly: "Renewables require massive storage to solve the fact that they are not dispatchable. But actually so does nuclear for completely different, economic reasons." What was it that you object to in that statement? What are you "debunking"?
Finally: As to the idea that energy systems are optimized for reliability first, and that renewables threaten this somehow:
Germany had an average of 12 outage minutes in 2020 on 49% renewables.
US: 280 outage minutes on 23%.
Germany outage minutes have been trending down as well last I checked, with the general explanation I have heard being that the focus on renewables has forced people to coordinate better, and check their grids more thoroughly than they did before.
That you can't compare two requirements when the consequences for failing to meet them are so different. To make an iffy comparison, you don't need brakes on a skateboard just as much as you need brakes on a car, even if a skateboard would stop a bit faster with brakes.
Incidentally, a few remarks on some unrelated points that were brought up:
> Not through centralized planning but by making sure we have a market where we pay for people to provide what is needed.
And we're seeing how well it's going.
> How to make sure that everything that is needed in order to have sufficient production capacity in all scenarios is also built is not in the responsibility of TSOs.
No, but as coordinators of the grid, TSOs have a lot to say about the impact and viability of production choices. There's a reason why TSOs publish their own studies on this topic.
> much more so than the hypothetical issue of under-supply in 10-20 years that you raise for which the basic organisational mechanisms are in place
I don't remember raising that point. Long-term supply volume decisions are a political choice, on which TSOs have no unique insight.
> Finally: As to the idea that energy systems are optimized for reliability first, and that renewables threaten this somehow
You keep bringing renewables in the discussion, I really don't know why.
I am not sure I see the point of continuing this. Other than I initially thought you clearly are knowledgeable, yet you refuse to cleanly argue your point. You attacked me directly for bringing up that storage has a role to play in nuclear as well as renewables, and now you claim that renewables are not the point.
I never claimed that they played the same role either. Again, why is that an issue?
That said, the point of storage for nuclear is exactly also that you don't build out the peak load, so if large scale storage failure leading to undersupply is your worry (as you indicate elsewhere), then that is a concern for this scenario as well.
But again, why? Storage backed energy grids are already a reality: we were running Europe on stored Gas for much of the winter. We are not talking about hypothetical batteries but about storing methane/H2 and operating gas power plants in these scenarios. Nothing in this tech stack is unproven by now, it is primarily a question of economics.
You insinuate (without clarifying) that markets arent working, yet we have fantastically reliable grids in Europe. Finally, the degree to which economics trumps reliability can be seen very directly in the energy-only vs capacity market debate. Energy only puts the critical safety decisions in the hand of market actors. Negative and very high positive prices in the market are supposed to incentivise building a base load that will only run for a few weeks a year and feeding it with flexibly produced gas/storage. Capacity markets put the decision how much of this to build I. The hands of the planners and engineers instead. Much to the horror of most engineers and planners I know energy-only markets won the political debate a few years ago. It seems politicians really hate giving engineers money to spend on reliability directly.
This debate probably would work if we were at a bar or conference, but it's not really clear it makes sense here...
It's not a very large point, and I believe I fleshed it enough already.
> so if large scale storage failure leading to undersupply is your worry (as you indicate elsewhere)
I don't remember mentioning that. If we work under the hypothesis that we have large scale power supply available at reasonable cost, then yes, there is no reason not to use them. Currently, pumpable hydro is the closest we have, and it's more or less capped out here.
> But again, why? Storage backed energy grids are already a reality: we were running Europe on stored Gas for much of the winter.
This is the first time I hear someone mention gas as storage, in the context of a power grid. If you forget emissions, then, I guess, why not. But if you forget emissions, 90% of the public discourse on the european power grid stops making sense. To date, I have knowledge of no large-scale environmentally viable way to produce this fuel in a renewable way.
> You insinuate (without clarifying) that markets arent working, yet we have fantastically reliable grids in Europe.
The grid was already working well before the introduction of markets. Since then, in my neck of the woods we have seen a complete failure of investment in the production side. In other countries that already had a built grid like us, renewal was only possible with heavy public subsidies.
I would welcome an explanation on what you believe markets brought to an already working grid.
Power2Gas has been a major topic. And the idea that this will become highly relevant in about a decade is behind the idea to allow Gas infrastructure investment as Green in Europe. This means Hydrogen but also synthetic natural gas.
They also cite something I haven't personally read, but which goes back all the way to 2009, again with hundreds of citations:
M. Sterner, Bioenergy and renewable power methane in integrated 100%
renewable energy systems, Ph.D. thesis, Kassel University (2009).
Of course as the roundtrip efficiency is better, its preferable to store Hydrogen directly if that is feasible (and this is why a pure electricity sector optimization model will never show methane).
But fundamentally the idea has been for a long time to run Gas power plants on carbon neural gases. This is an explicit point in the EU Taxonomy of labeling Gas investments as green. They can only do so if they retrofitted to running on carbon free gas from 2035 onwards. Siemens is selling their stuff as H2-ready for that exact reason [1].
Pumped hydro can not be meaningfully expanded, its only a small part of the overall solution.
I can see that there's a lot of momentum for that, indeed. But as you told me earlier, we moved from a system where engineers and planners offered options to choose from to a system that is driven by political will, and implementation concerns come down the line.
Both systems have their flaws: the first one is clearly detrimental to democratic oversight, and may sometimes cause authoritarian problems, where administrators don't see or overlook problems caused to individuals.
On the other hand, political-first systems tend to kill unviable or uncompetitive projects way too late, because implementer signal is attenuated.
A good example of this is the development of nuclear power in France and the UK in the 60's: both countries had a local reactor project which was politically favored. France, where engineers had a strong influence on politicians, killed it quickly and bought US licenses for its program. The UK on the other hand moved on with their local graphite-gas reactors, which proved much harder to implement, and hampered their program.
All of this to point out that power2gas is currently at a very early stage, and since this program is dominated by political will, it's extremely hard to know how well it will work, let alone have a good idea of the economic figures.
Maybe it will work. I hope so. But it's certainly not a done deal, and it's extremely unsettling to see our countries' energy safety be debated based on a few scientific papers or a planned demonstrator by people that won't have to actually implement it.
The biggest downside (compared to solar wind) of nuclear always was payback time on investment.
Solar wind is volatile and non-dispatchable, so you need something to balance it. Of course we can always say heck it and live with constant brownouts and highly variable energy cost, but that is a non-solution in my book. You can overprovision generation, you can build dispatchable storage solution or dispatchable alternative generation source. In the end you need this because of variability and non-dispatchability of solar wind. Nuclear does not have this property, ergo it does not need storage to prevent brownouts. Sure, some models suggest that storage could under certain circumstances maybe help shave off a few percent of the cost, but that is the extent nuclear needs storage.
And this brings us back to original issue of payback time. Solar wind has lower payback time, because the cost of variability is borne by the grid, i.e. classical example of privatizing the profits and socializing the losses.
Not really. Both overprovisioning and dispatchable storage are hugely expensive, therefore dispatchable alternative generation is employed, which is gas. So in an attempt to move away from carbon-emitting generation these models make carbon-emitting generation integral part of the system.
What models based on renewables actually do is try to find a problem for a solution: throw away grid stability requirements out of the window altogether, introduce huge variabilities and hope that spending power inequality will mask brownouts, i.e. it is hoped that pricing changes and consumer reaction to those changes will be fast enough for load to disconnect voluntarily before parts of grid are forcibly disconnected.
Please show a single publication that does what you claim it does. A single one.
I don't think they exist, or if they do they will not be the prominent highly cited ones. Yes, storage and methanation and electrolysis are expensive. These expenses are explicitly modeled in the energy system models. Modeling these expenses for a complete system that satisfies the security of supply constraints is the very essence of what these models do [1]. Criticism against them would be exactly that they don't assume some market/price dynamics but a perfect central planner.
Flexible loads are a fundamentally different thing than brownouts. Electricity consumers opt in to being flexible, and this is about sophisticated industrial consumers, not private consumers anyway. The market mechanism you describe would only be true for energy-only markets anyway, and no one is proposing energy only markets for primary and secondary control energy that balances out short term variability.
[1] E.g. Figure 7 in https://arxiv.org/pdf/1801.05290.pdf gives the cost breakdown for a 0-Carbon configuration of generation storage (and optionally transmission expansion) investment that can serve all loads for the entire year under different assumptions for other energy sectors participation in flexibility provision. While this modeling set up is a lower bound on the costs, a deeper analysis shows that this is actually pretty accurate especially when storage investment is reasonably high, as the overall storage cost is dominated by seasonal variability which is highly regular.
There is no reason to assume that the downsides of various other techs are in any way more manageable. (And ironically some of the solutions proposed for the downsides of nuclear are also what you need for renewables, i.e. storage to maximize use of expensive infrastructure with low opex.)