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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

#51

Post by threeseed »

hannob wrote: post #48
chrisco255 wrote: post #39

Earlier quoted context omitted.

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

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.

Especially if there are advancements in power distribution e.g. high temperature superconductors.

This would be a game changer for the major continents like Europe, US, Africa where you could have power coming from hydro, thermal, solar, wind etc and being shipped to where it is needed.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#52

Post by ed_balls »

mkl wrote: post #23
ed_balls wrote: post #14

I've been thinking about this for a bit and had a similar model in mind. You build small nuclear reactors in a containers - similar how Google builds their DC. You find an abandoned coal mine shaft and put them deep in the ground. The cost optimizations come from: - economies of scale - no decommission costs - you just leave them to decay. - fewer security measures.

Wouldn't you need a water supply for steam turbines? And if there's water in your mine, it seems like it could transport radioactive particles out.

Yes, you need to exchange heat, most likely water since it's most cost effective.

> And if there's water in your mine, it seems like it could transport radioactive particles out

You need to pick a really deep and isolated shaft (Some gold mine shafts can reach 4 km)

Re: Rolls-Royce plans mini nuclear reactors by 2029

#53

Post by mkl »

jacobush wrote: post #25
mkl wrote: post #18

Earlier quoted context omitted.

I don't think that would generate enough power for a car. See maximum output of some here: https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

Sure it would. Couple it with a lion - battery as a buffer. A tiny pellet gives 60 watts of heat. A heat cycle engine could recover maybe 10 watts of that. Put 500 pellets in there and you could get 5kw or so electric charge, all the time. Of course the pellets are insanely toxic in just about every way.

Are you sure? If I'm reading the "Terrestrial" table on that Wikipedia page right, 5kW of electrical power would need an RTG weighing many tonnes, significantly more than a bus.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#54

Post by dmos62 »

luspr wrote: post #35
grabbalacious wrote: post #15

>Environmentalists are divided over nuclear power, with some maintaining it is dangerous and expensive, while others say that to achieve net zero emissions by 2050 all technologies are needed. Yes, a mix of technologies. But there's more to it than that. We're going to need increasing amounts of power in the future to explore the solar system and to solve all kinds of existential problems. Energy usage is not inheren…

Agree completely. It's a fallacy to believe we will require less energy in the long run. We need much more, if we want to advance as a species.

> we want to advance as a species

I'm somewhat weary of people talking of civilization progress as if its definition is obvious and universal.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#55

Post by LeonM »

TeMPOraL wrote: post #11
LeoPanthera wrote: post #6

Earlier quoted context omitted.

Would a nuclear powered EV ever need refuelling?

It'd probably need to replenish the liquid (e.g. water) used for reactor cooling/energy extraction.

I don't know about the thermal efficiency of a small nuclear reactor, but I imagine you could probably make that a closed loop system. Just as you would on an internal combustion engine, with a radiator to cool/condense the heated coolant.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#56

Post by Retric »

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.

That’s one of those ideas that seems great on the surface but is much more expensive to implement than you might think. Moving heat around involves significant energy loss over long distances. That’s offset with combined heat and power generation which is very popular in Russia etc, but on it’s own it’s a tougher sell.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#57

Post by Retric »

pauljurczak wrote: post #45
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.

Baseline power based on batteries is not practical yet and it won't be for a while. Way too expensive and resource intensive.

Solar + batteries averaged over the 24 hour demand curve are cheaper than current generation nuclear power plant operating 24/7/365. The issue is turning off nuclear power plants don’t significantly reduce costs so their competing head to head vs x hours @ 2c/kWh + y hours @ ~20c/kWh.

At first glance it seems to slightly favor nuclear when it can operate 24/7, but nuclear power plants have a very long lifecycle 40+ years and projected battery costs for future replacements are lower than today’s values. Worse nuclear has a much longer lead time so you already need to compare battery prices ~5 years from now when you’re looking at building a new nuclear power plant.

PS: Note grid batteries are significantly cheaper when they can share inverters with solar generation and be directly charged via DC. Standalone prices are higher. Also, fast discharge peaking power reduces battery lifetimes over longer discharge nighttime useage.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#58

Post by LeonM »

thomasedwards wrote: post #5

I really wanted this to be about Rolls-Royce Motor Cars Limited rather than Rolls-Royce Holdings plc. A nuclear-powered Rolls-Royce Phantom would be incredibly boss.

Actually, several American car manufactured experimented with this idea in the 50's. Most notably Ford with the Nucleon [0], but also other brands such as Packard and (I believe) Cadillac were also designing nuclear powered cars.

Eventually it was concluded that the shielding of the reactor would make a nuclear powered passenger car impractical, as it would make the vehicle too big. And of course there were the obvious safety concerns.

There is an good documentary on this subject on youtube [1].

[0] https://en.wikipedia.org/wiki/Ford_Nucleon [1] https://www.youtube.com/watch?v=kR5gefU87TY

Re: Rolls-Royce plans mini nuclear reactors by 2029

#59

Post by LatteLazy »

EliRivers wrote: post #31
LatteLazy wrote: post #20

Lol, a technology we can't make work economically WITH economies of scale and on site experts will now be offered without those benefits.

Is this not what we expect from technology? That over time it becomes commodified and increasingly easy to operate?

No, in a word.

You expect a technology to be made to work first, then to be made to work profitably, and only then commodified, miniaturised, etc.

Nuclear works, but no one has made it work profitably. There is no reason to think shrinking it will make more profitable.

Quite the opposite in fact: nuclear has big fixed costs. That's why you usually see multiple reactors build close together on single sites. The more profitable (less loss making really) sites are the biggest ones.

This is why the first computers were not laptops.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#60

Post by rjsw »

imtringued wrote: post #44
mytailorisrich wrote: post #27

Earlier quoted context omitted.

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

Rivers tend to have different flow rates over the course of the year. If there is a heat wave the plant may not have enough water for cooling. The ocean is more dependable.

France has some nuclear plants that are on rivers where this problem has been seen.
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