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Rolls-Royce plans mini nuclear reactors by 2029

bbc.co.uk

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Re: Rolls-Royce plans mini nuclear reactors by 2029

#101

Post by christophilus »

radicalbyte wrote: post #33

We shouldn't be using nuclear energy for power. Solar, wind and batteries will solve that. What we should be doing is using nuclear energy for HEAT. We need a LOT of heat for a variety of chemical and industrial processes, not to mention heating of homes in colder climates. For these uses nuclear fission has massive potential.

I wonder, though, how much we could bring the price of nuclear down if we were to actively develop the technology, rather than letting it languish. I also wonder how much toxic waste batteries will produce vs nuclear. Do we have clear numbers on that?

Re: Rolls-Royce plans mini nuclear reactors by 2029

#102

Post by hannob »

belorn wrote: post #94
hannob wrote: post #48

Earlier quoted context omitted.

I'm always baffled by such statements. Can you explain in which way solar is not a "near-infinite source of energy"? I mean... there are without doubt technical challenges and all that (but arguably less technical challenges than to do the same with nuclear), but there really is no relevant limit to the deployment of solar cells if you include things like large-scale installations in the desert.

What I have heard, you do loose energy in transmitting power over large distances. There exist low loss transmission cables, but I don't know how effective that is over very great distance. There is also the question of how to redesign a distributed power grid into a centralized version where all the power comes from a single sources in desert areas. On top of that there are political challenges. I have a hard time i…

The Sahara thing is ultimately just to illustrate that there's no real limit to solar energy (because the upper commenter claimed that nuclear is the only energy that is practically limitless). But of course in practice you'd do the easy things first - that is, build solar on every rooftop. No country is anywhere close to that.

I guess in the future we'll use imported solar for hard to solve problems, e.g. turn it into hydrogen or synthetic fuels (which also makes the transmission loss problem much smaller), while our electricity needs will be served mostly by local wind and solar.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#103

Post by belorn »

neuronic wrote: post #82
erulabs wrote: post #64

Earlier quoted context omitted.

Solar power is simply indirect nuclear power anyhow. If we can do what’s happening in the sun in a bottle - then no need to produce panels. If there is material in stars to produce solar power, then there is more potential nuclear power. I’m for both, and solar seems distributed in a way that makes me think it’s better for human society, but since stars are made of fissable materials - by definition there is more “po…

Solar is fusion and not fission [1]. If you can't even get that right, why should anyone take these weird pro-fission arguments seriously in 2020? The solution is to keep using existing nuclear power and develop renewables for replacement. Nuclear fission plants take at the very least 10 years (!!) to go online from the day construction begins. And that leaves out years of planning and dealing with contracts. It's to…

Renewables are not a replacement for existing nuclear power unless you either add fossil fuels or batteries to the mix. Countries which currently are replacing nuclear power do so with a combination of renewables and fossil fuels, with fossil fuels burning when renewables are not producing.

Batteries, usually reverse hydro power, is an interesting future technology. Some argue it is significant more developed than fusion. The bigger question is if its economically competitive compared to fission. There is costs and energy loss in every single step of producing electricity from renewables, transmitting it to the battery, converting it into potential, recreate the electricity, and finnally transmitting it to the end users. With fission you go directly from the power plant to the end user. Reverse hydro power plants also take a long time to build and either use a lot of land or coast. If you build it on land it also release a lot of methane as top layer of the land decompose.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#104

Post by VLM »

mytailorisrich wrote: post #27
ptah wrote: post #24

an aside: why d nuclear reactors have to be built on the coast? does that not make them more vulnerable to natural disasters

They rely on water for cooling so are built near a source of it, be it the sea or a river.

OP is probably asking some variation of why not build them on a canal rather than literally right on the coast, Fukishima-style.

Part of the problem is the components are very large and very heavy even for industrial projects and coasts have barges and seaports.

Some parts are too heavy even for railroad shipment, so its barge and crane or expensively fabricate on site, or expensively assemble on site.

Its quite a logistical headache to build a large nuclear reactor. Yes, submarine scale plants are petite, but GW-class baseline generators have very large and heavy parts.

WRT to Fukishima, its probably cheaper and more efficient from an engineering perspective to build a massive seawall than an unblockable long canal. The effort and concrete required to build an unblockable kilometer long canal that would survive a 30m tsunami would probably survive a 100m tsunami if put into a seawall instead. Or more likely, management would only permit a 10m rated seawall (or canal) "because that'll never happen" and we all know how that turned out.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#105

Post by rusk »

posix_me_less wrote: post #95
rusk wrote: post #50

Earlier quoted context omitted.

Forgive me if this is a worn trope, but I've read somewhere that the upper bound on what we can do with nuclear energy is not how much we can produce, but what we can do with the leftovers ... as more and more people use nuclear power we're going to produce more and more nuclear waste, and there isn't really any answer as to what we can do with that. There are plenty of fantastic "ideas" as to what can be done, but i…

> we're going to produce more and more nuclear waste, and there isn't really any answer as to what we can do with that. There are several answers to the question "what we can do with it", such as 1) reprocess it and use it again; 2) keep it in the power plant pools or similar storage facilities; 3) dump it to some deserted place where it isn't a big problem (high depth, stable earth crust). In the past, UK just dumpe…

I didn't think nuclear waste could be "burned" ... I was given to believing that containment was the only option right now.

I'm familiar with your (1) (2) (3) items, but again, from what I've read these aren't fully satisfactory. (1) is probably ideal but hasn't really been cracked, (2) and (3) are just different facets of containment, but (3) is admittedly the most plausible right now.

We can tolerate a limited amount of this for sure, while we work on other solutions, but unless this question gets resolved it will hamper the widepsread adoption of nuclear.

The UK approach is interesting because yes, they just dumped it in the Irish sea. There's a deep underwater ravine between Scotland and Northern Ireland where it's all dumped, along with various other bits of old military hardware and other bits that are inconvenient.

Think about that the next time you here Bojo talking about building a bridge to Northern Ireland.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#106

Post by rusk »

christophilus wrote: post #91
roenxi wrote: post #72

Earlier quoted context omitted.

If literally all the electricity ever produced by the human waste had been produced by current generation nuclear technologies, there would be a small hill of high-level nuclear waste somewhere. It wouldn't be an issue except locally where it was stored. To believe that is a problem is to not have grappled with just how big the world is and how much of it is uninhabitable to humans already. The human population is co…

Nuclear energy has a PR problem that is very hard to solve. It doesn’t help that movies dramatize it. From what I remember, the only people who died due to Fukushima were those that died of fear. The reality is that nuclear is remarkably safe, clean, etc.

I'd imagine the death toll from Fukushima will probably not be fully estimable for a few years yet.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#107

Post by gonational »

socialdemocrat wrote: post #29

Sure why not, but let us not get carried away and think THIS is the solution to global warming. It is unproven, it will be too late, and not scale up quick enough. By unproven I mean that the economics of it is unproven. We have no proof that SMR will be cheaper than large reactors. The article points this out as well. By late I mean at current fast pace of development a lot of will happen with wind and solar in the…

Nothing is ever enough.

The only solution is to give our money to the overlords.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#108

Post by dsfyu404ed »

rusk wrote: post #50
chrisco255 wrote: post #39

Earlier quoted context omitted.

Yep, and nuclear is the only near-infinite source of energy.

Forgive me if this is a worn trope, but I've read somewhere that the upper bound on what we can do with nuclear energy is not how much we can produce, but what we can do with the leftovers ... as more and more people use nuclear power we're going to produce more and more nuclear waste, and there isn't really any answer as to what we can do with that. There are plenty of fantastic "ideas" as to what can be done, but i…

A quick google search says if we only used nuclear we'd get 40g of waste per person per year assuming western energy consumption standards[1].

Multiply by 8*10^9 people (a little more than the current world population) and you get 320,000 metric tons which is about 3/5th the capacity of the largest oil tankers.

Finding a place for that much waste per year is a political problem, not a technical problem. There's plenty of geologically "safe enough to outlast the radioactivity" places we could dig a deep hole (thanks to the fossil fuel industry that is a solved problem) to dump that much waste into.

[1] https://whatisnuclear.com/assets/waste_per_person.pdf (no idea on source bias here, I didn't read the whole thing)

Re: Rolls-Royce plans mini nuclear reactors by 2029

#109

Post by [deleted] »

christophilus wrote: post #91
roenxi wrote: post #72

Earlier quoted context omitted.

If literally all the electricity ever produced by the human waste had been produced by current generation nuclear technologies, there would be a small hill of high-level nuclear waste somewhere. It wouldn't be an issue except locally where it was stored. To believe that is a problem is to not have grappled with just how big the world is and how much of it is uninhabitable to humans already. The human population is co…

Nuclear energy has a PR problem that is very hard to solve. It doesn’t help that movies dramatize it. From what I remember, the only people who died due to Fukushima were those that died of fear. The reality is that nuclear is remarkably safe, clean, etc.

[deleted]

Re: Rolls-Royce plans mini nuclear reactors by 2029

#110

Post by rusk »

roenxi wrote: post #83
rusk wrote: post #74

Earlier quoted context omitted.

Yeah man, I dunno either ... I think "poisonous" is understating it somewhat. We're talking about substances that will remain toxic for thousands of years, and are quite happy to go everywhere they can if there is some issue with containment. I appreciate that you have a conviction that this is a problem, but you're coming across a bit hand-wavy in your arguments. I'd prefer to see concrete solutions (and I don't mea…

> you're coming across a bit hand-wavy in your arguments. I'd prefer to see concrete solutions It is an order-of-magnitude argument; a bit like arguing whether $1 billion or $1 million is more dollars. The difference between the two figures is almost exactly a billion dollars because there really is no comparison between orders of magnitude. Uranium is something like 6 orders of magnitude more energy dense than fossi…

You're comparing magnitudes there ... but I've a feeling there's a base-rate somewhere, relating to how dangerous just a relatively small amount of nuclear waste can be if it gets into groundwater or something.

The real problem with nuclear is that it's a one way only system. The effects of other forms of fuel can in theory be sequestered eventually. Sequestration of nuclear waste is exactly something that yout don't want to happen.

As you say, it's a matter of scale. A limited amount of nuclear power is probably fine, and safe. But it can never be the "solution" to our energy problems until the various problems are solved satisfactorily.

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