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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#511
post #388

Earlier quoted context omitted.

Only residential has fixed prices for electricity over the day. Industrial electricity has always been sold in variable prices, e.g. furnaces and other large consumers run when power is cheap and go into hold mode when it is expensive. There even is a large discount if you allow the power company to switch your consumption on/off. All that is already a reality and has been for decades. Which goes to show: there still…

But still "base load" is no law of nature. Half the market is on fixed price, and regulation has so far dictated that there has to be a lot of "base load" type power production, and without co2 externalities priced in that's been profitable for producers too. But it's all rules and tech we invented and can be changed. The amount of supply following the current industrial users are incentivised to do, and the requisit…

"base load" is also a statistical law of nature. Your consumers might want or need to consume your product regardless of the price. I will run my heating before I freeze to death, and I will thaw a meal before I starve. Somebody will switch on their lights in the dead of night. The hospital will run its MRI when an emergency arises.

All these things are rather randomly occuring things, some correlated, some uncorrelated. All these create a "ground noise" of consumption. All these things lead to a need for baseload power, which can only be removed by switching off the grid.

Re: Ultra Safe Nuclear

#512

Earlier quoted context omitted.

Repeating myself for the 3rd time: There are other options beside solar power, so why keep harping on this? In fact Denmark gets about 65% of their power from wind. The UK also gets a lot of their power form wind. For many norther countries, wind power has quite a lot of potential.

> In fact Denmark gets about 65% of their power from wind. Not true. Just 47% [1], and Denmark is a country with the most favorable conditions for wind generation. Statistics are easy to manipulate if you allow yourself to add 15 percent here, subtract 15% there.. Also, Denmark relies on Sweden (who utilize nuclear power a lot) and Norway to provide power when renewables are not providing enough power [1]: https://ww…

I am talking about 2020:

https://www.carbonbrief.org/analysis-coronavirus-has-cut-co2...

You refer to 2019 when renewables gave 50% of Danish power.

> Also, Denmark relies on Sweden (who utilize nuclear power a lot) and Norway to provide power when renewables are not providing enough power

Yes, but the capacity for import and export is limited. Despite these limitations Denmark has managed to run on 65% wind power in 2020 without breaking the grid.

Thanks to COVID19 we get a look at the future in terms of how much of electricity production renewables can handle.

Re: Ultra Safe Nuclear

#513
post #475

Earlier quoted context omitted.

> But breeders themselves are uncompetitive Hard to say. Hasn't really been commercialized to the point one could make any definite conclusion. There's nothing inherent in a breeder reactor that would make it substantially more expensive. > and fast breeders are inherently dangerous, since they require much higher concentrations of fissionable material, and could potentially experience fast prompt supercriticality in…

All the attempts at building breeders have experienced serious problems, and estimates of their cost are higher than for thermal reactors. > No. In a fast reactor the prompt neutron multiplication time is an order or magnitude faster than in a thermal reactor, but still several orders of magnitude slower than in a weapon. One could still have prompt supercriticality. So, even if the neutrons are slower than in a weap…

> All the attempts at building breeders have experienced serious problems, and estimates of their cost are higher than for thermal reactors.

Nope. EBR-II back in the day had no big problems over it's lifetime. In Russia there are a couple of relatively big ones producing power, with no big issues.

But crucially, so far all breeder reactors have been one-off things done for R&D purposes. They haven't been optimized for producing low cost power, and there has been no learning curve either since all have been bespoke designs.

Then again, in the west we have failed to build even traditional LWR's on time and budget, as well as other large projects.

> So, even if the neutrons are slower than in a weapon, they are still much faster than in a thermal reactor, so the doubling time could be much shorter.

Yes, but not short enough that a non-trivial fraction of the fuel would fission before the assembly would disintegrate.

> There's also the possibility that, because the core contains tons of plutonium, the rearrangement driven by the supercriticality could cause the arrange to become MORE reactive, not less

Now you're just concern-trolling. If part of the core becomes supercritical due to melting, in the absence of cooling that would vaporize the supercritical part of the fuel, reducing its density and pushing everything else outwards, thus reducing the neutron multiplication. Melted fuel flowing is just a much too slow process to rapidly cause a big bunch of fuel to become prompt supercritical.

Nuclear weapons are very Very VERY carefully engineered so that a substantial fraction of the fuel fissions before the assembly blows apart. Nuclear reactors OTOH, including fast reactors, are very Very VERY carefully engineered so this won't happen even in the most wildly imaginary accident scenario.

> For this reason I suspect that nothing but a fast MSR could be licensed in the west.

Oklo Inc. is in the process of licensing their fast reactor having submitted the application this year. Presumably the believe they have a decent chance of having their license application approved.

There's also the Versatile Test Reactor(?) which the US government is planning to build. Essentially a PRISM reactor (evolved from EBR-II / IFR) modified for materials testing rather than power production.

> You will note that the French have now abandoned Astrid, which was to be their next attempt at a prototype fast reactor.

Yes. I was never a big fan of ASTRID, AFAICS there wasn't anything really innovative there that would have brought any major new insights. Still disappointing though.

Re: Ultra Safe Nuclear

#514

Earlier quoted context omitted.

I'd suggest looking through Lazard's levelized cost of energy slide decks. The unsubsidized price of renewables is indeed substantially less than nuclear. Next look at the time scales for building new nuclear. Then look at the trend lines in the cost of storage, particularly utility scale lithium batteries. You don't have to be a genius to realize this makes new nuclear a bad bet purely on the finances. Even if you w…

> Then look at the trend lines in the cost of storage, particularly utility scale lithium batteries. You don't have to be a genius to realize this makes new nuclear a bad bet purely on the finances. You are off by more than one order of magnitude! For non-hydro renewable to be self sufficient, you need between 200h and 600h of storage[1]. So to replace a 1300MW reactor, you need 3000MW of renewable power (assuming 33…

> For non-hydro renewable to be self-sufficient, you need [8-25 days] of storage.

If you're adamant on generation following load, low transport, probably no overgeneration, no hydro and absolutely no backup biomass, gas or similar, then yes, you probably need 25 days of storage.

It would be good to have at least a couple of days or weeks of energy buffer in the world's supply chain, but that can take many forms. Electricity and lithium batteries seem a bad choice for the bulk of it.

Re: Ultra Safe Nuclear

#515
post #244

Earlier quoted context omitted.

I'm a little disappointed that the Levelized cost of energy link does not include, you know, the levelized cost of various energy sources. Also, it doesn't include the number of hours needed to find and debate a place where you can actually put down renewables. Places using the most power (those most densely populated, like the Netherlands where I come from) have enough space for nuclear reactors to keep the country…

There’s really no reason why Netherlands can’t import power from its allies. It already does.

Huh, where did I give the impression that we can't? I'm saying that we'd be dependent, implying that we can because otherwise we couldn't be dependent.

Today we might import power because it's cheaper, but we can build another coal or nuclear plant and produce that 10% we're currently importing. Building enough solar panels or wind turbines, on the other hand, to produce 1093TWh/year (2014 figure) is going to be difficult. Even if it's only about electricity and we keep on heating with oil and driving oil-powered cars, we need 112TWh/year (2014) of electricity.

Yes, we're building wind turbine farms in sea, but "we're hoping that'll get us from 14% to 16% renewable energy by 2023"[1]. It's more than a rounding error, but not by much.

[1] https://en.wikipedia.org/wiki/Wind_power_in_the_Netherlands

Re: Ultra Safe Nuclear

#516
post #432
post #244

Earlier quoted context omitted.

I'm a little disappointed that the Levelized cost of energy link does not include, you know, the levelized cost of various energy sources. Also, it doesn't include the number of hours needed to find and debate a place where you can actually put down renewables. Places using the most power (those most densely populated, like the Netherlands where I come from) have enough space for nuclear reactors to keep the country…

Mea culpa; usually I add more references to these comments - it's become a little tedious to look them up and include them each time so I skipped them for that comment, but since you're engaging in good faith, here are a couple: * https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.... (US Energy Information Administration; see Table 1b & Table 2 on page 7 & 8) * https://assets.publishing.service.gov.uk/gover…

Thanks for the links!

I don't agree with everything you wrote, but your comment showed as downvoted and I don't get that. Your comment definitely contributes to the discussion, so at least have an upvote from me.

So what I'm seeing in those tables is (taking the UK 2025 central expectation, converting pounds to USD):

                UK   US   UK   US
    nuclear    123   75  baseline
    wind sea   130  122  0.9x 0.6x
    wind land   79   40  1.6x 1.9x
    solar       82   33  1.5x 2.3x
    hydro      n/a   53  n/a  1.4x
I think I read someone else in this thread claiming 10x the cost. Apparently that's not the case, but it's indeed still ~2x the cost of solar and on-shore wind, though actually cheaper than wind in sea (which is what the Netherlands will rely on in large part).

Even if it assumes zero time is spent arguing over where to put each wind and solar farm and that there is no downside to losing the physical space it's built on, 2x the cost is a large difference so I see how it makes financial sense to try going for renewable energy.

> My hope would be that groups of countries see energy provision as a shared problem that they can co-operate on (in the true sense of a shared grid)

That's already the case. See the map on the right: https://en.wikipedia.org/wiki/Synchronous_grid_of_Continenta...

> I hear you regarding regional and national concerns, but if anything I think that reinforces another argument for renewables: they are relatively easy to construct and decommission over shorter timescales if political and local pressure demands it

I'm not concerned that my national government will not align with my regional interests. My "regional and national concerns" are that it's nigh impossible to produce enough renewable energy with the physical space we have in the Netherlands. I'm all for nuclear, and I'm also fine importing renewable energy from Germany, Norway, and/or the UK (what are the odds that they all decide to screw us over at the same time? So that should be fine). We just have to realize what the consequences are of phasing out nuclear energy: dependence and delaying the transition by waiting for other countries to do it for us.

We need our neighbours to do a large effort on our behalf in finding places where people are okay with having solar/wind/hydro so that they can export it to us, and most of that effort could be avoided if we weren't antsy about paying more money for our energy for the benefit of making big steps in transitioning away form coal and gas.

It's probably too late by now. Even if tomorrow everyone woke up and decided nuclear is shiny technology to expand, it would take too long. But we're also too late starting on renewable energy, so the question is: which is the better option?

Option 1: mix 50% renewable power with 50% nuclear and be sure that energy production is nearly CO2-neutral when those plants are built in 15 years. Bam, done. From there, we can start to replace the nuclear part with renewable energy (either by helping or kindly asking other countries to build it in their space and sell the resulting power to us, or find more efficient ways to do it locally). Note that we'll still need to do a huge effort to achieve 50% renewable energy in the first place, so this is not the easy way out. It's a hard way, but maybe-realistic way. In 15 years, the earth will have warmed up more than it should have, but what's the alternative? Well:

Option 2: do our best on renewable energy and win thousands of fights with local communities and nature preservation organisations, while asking neighbouring countries to kindly produce a decent chunk of our electricity need in a sustainable fashion (while they're also trying to turn old power plants off, it's not as if they have capacity to spare). Hopefully we'll get to be nearly CO2-neutral at some point, maybe in a few decades? It's hard to say.

> I'd [be] interested to know if the Netherlands is relatively advanced in terms of home and business energy efficiency

I honestly can't say. We're doing better than the USA but that's not difficult. So far as I can tell, it's not more advanced than any other western European country. Having lived about 10% of my life in Belgium and 10% in Germany, and having had long holidays in France, the Netherlands feels five to ten years ahead of those countries in many ways. While the details of that feeling are a topic for another time, I don't think we're doing better in terms of energy efficiency.

> if political and local pressure demands it

Local demands can go screw themselves. East Germany has a higher nazi quota than west Germany but we're not saying "oh that's alright, you go ahead and send the black people in your area back to where they came from, make gay marriage illegal again, etc. Local power for the win!".

Locally, nationally, and internationally we're not doing what's in our own best interest, long-term. I don't mean nuclear power, I mean becoming CO2-neutral in any way. Thirty years ago we were pretty sure what was going on and we did absolutely nothing; ten years ago we were pretty damn sure the climate was already changing and noticed a huge extinction event on our hands and we figured we should get started; today it's absolutely certain that we're facing an existential issue, kids are out on the streets every friday telling us to do something, and what are we doing? Debating whether we really want to pay 38ct/kWh instead of 25ct/kWh by adding 50% nuclear into the mix. Oh yeah, and the USA decided they don't need to participate, it's not profitable in the short term or something. Other countries be like "sure that's fine, you have your own opinions and twice the pollution per capita of the rest of us. That's perfectly fine, this changes absolutely nothing in our relationship."

Re: Ultra Safe Nuclear

#517
post #508

Earlier quoted context omitted.

And yet, the cost of a kWh from renewables is less than from nuclear, for all the supposed advantage of nuclear's energy density. This should tell you that energy density is not actually a good metric.

Comparing a source controllable uninterrupted source of energy with an unreliable intermittent one doesn't make sense. Having power when you need it is very valuable. And in the case of renewables, you'd need to account for storage, after which the prices explode. What would you say if you could only turn on AC in the 3 months of winter? But there is another ugly side with regards to price (which are heavily subsidis…

Intermittency and power density are two entirely different things. I was addressing the former there. But elsewhere in this thread, I address the intermittency issue. Constancy is an advantage, but not an unlimited one. If renewables have a sufficiently large levelized cost advantage they can push nuclear entirely out of the picture, even though they are intermittent.

Re: Ultra Safe Nuclear

#518
post #513

Earlier quoted context omitted.

All the attempts at building breeders have experienced serious problems, and estimates of their cost are higher than for thermal reactors. > No. In a fast reactor the prompt neutron multiplication time is an order or magnitude faster than in a thermal reactor, but still several orders of magnitude slower than in a weapon. One could still have prompt supercriticality. So, even if the neutrons are slower than in a weap…

> All the attempts at building breeders have experienced serious problems, and estimates of their cost are higher than for thermal reactors. Nope. EBR-II back in the day had no big problems over it's lifetime. In Russia there are a couple of relatively big ones producing power, with no big issues. But crucially, so far all breeder reactors have been one-off things done for R&D purposes. They haven't been optimized fo…

No, not concern trolling. Designs where rearrange of the assembly increases k were explored for weapons. They were not pursued because they were large and required lots of fissionable material. But a fast reactor core has orders of magnitude more material than a bomb. The regulators will require proof that this scenario is very unlikely, not just an assumption. And that's going to be difficult to provide.

Re: Ultra Safe Nuclear

#519
post #407

Earlier quoted context omitted.

Germany alone spends ~$1.2 trn (that would be ~4.8trn on a population adjusted basis for the USA) on the Energiewende, and Germany is far away from being 100% renewables. The EU now plans to invest another trillion € till 2030. A lot of money is poured into renewables.

Yep, there is a lot being done today of course and progress has picked up in recent years. But knowing what we know, it's still underfunded.

And Germany has the most expensive electricity on the planet (for a firstworld nation and adjusted to cost of living). Funding is drying up because renewable subsidies make power unaffordable and thus politically unviable. Germany should be a big warning to everyone claiming renewables would be cheap or cheaper, the market here is gravely distorted by subsidies and yet, people point to Germany as an example...

Re: Ultra Safe Nuclear

#520
post #502

Earlier quoted context omitted.

EROI of renewables is just fine, and getting even better. Attempts to argue it's not have been thoroughly debunked. About land area: you said this "I'm making the claim because it is painfully obvious that unless you're making calculations about spherical cows there's nowhere near enough resources, surface, and specifically predictability to have renewables be more than marginal for a long time." If land area (which…

There is enough surface to put PV panels in many places, and the reason why I don't just say land is because enthusiasts will also consider rooftops (which aren't optimal in terms of tech and output as you surely know - the significant farms do require requisitioning actual land and it isn't insignificant in itself[0]). But there isn't enough surface for PV to preclude the usage of nuclear, which is what I've been sa…

And I'll pre-emptively add that I've mentioned about 3 or 4 times already that there's a scenario that involves the possibility of exclusively banking on renewables, and that scenario is the de-growth mentioned in my very first post too. It is entirely possible to go there (and in fact, it is where we're bound for ultimately from a purely physics-based understanding of fossil fuel depletion, which includes uranium and therefore nuclear ending too).

So the real question actually will be one of consumption (of goods and energy), and if we're willing to ask and answer that question before we reach critically low levels (so at an absolute stretch within about 2 centuries) then we will be in a position to totally live off of energy sources that we can approximate as infinite (much more robustly so than what we did with fossil fuels, since the sun and wind for all intents and purposes would not go before we do).

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