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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

#131

Post by the8472 »

dmos62 wrote: post #100
the8472 wrote: post #88

Earlier quoted context omitted.

As far as humans are concerned overall progress has been linked to climbing up fractions of the kardashev scale since fire was invented. And even before fire, organisms could only become more complex as the energy available to them increased. You can't run a hummingbird or mammalian brains on photosynthesis directly, it's just not energy-dense enough.

> overall progress This thread is becoming recursive. Is organism complexity progress? Everyone might agree with you, or not. That's because progress is whatever we say it is. It's subjective, in that everyone can have a different view of it, and it's non-constant, in that you can change your mind whenever. Progress is such a loaded word today. I'm hardpressed to find more than a few words with so much cultural bagga…

I am saying that for many or perhaps even almost all measures of progress we want to apply, i.e. the specific definition doesn't matter, that progress was either enabled by or directly required more energy being available.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#132

Post by wolfram74 »

dmos62 wrote: post #100
the8472 wrote: post #88

Earlier quoted context omitted.

As far as humans are concerned overall progress has been linked to climbing up fractions of the kardashev scale since fire was invented. And even before fire, organisms could only become more complex as the energy available to them increased. You can't run a hummingbird or mammalian brains on photosynthesis directly, it's just not energy-dense enough.

> overall progress This thread is becoming recursive. Is organism complexity progress? Everyone might agree with you, or not. That's because progress is whatever we say it is. It's subjective, in that everyone can have a different view of it, and it's non-constant, in that you can change your mind whenever. Progress is such a loaded word today. I'm hardpressed to find more than a few words with so much cultural bagga…

Most quality of life improvements do take energy, and yes, quality of life is subjective, it is conceivable to imagine a mind that takes joy in their child dieing of a preventable disease, some vertebrates eat their young, but overwhelmingly, humans like to see their child get old enough to play and talk as well as laugh and cry.

Things like reliable and easy access to clean water, refrigeration for medicine and food, shelter against the weather, clothing, cleaning mechanisms for the above, all of these are non-equilibrium phenomena and so take energy.

So we either need more sources of power or fewer people. I'm glad that birth rates are falling, but lots of people don't have those basic technological tools, so energy technology will need to be rolled out or our definition of empathy will need to change to allow for lots of people to suffer.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#133

Post by jillesvangurp »

What's missing is a $/kwh quote. It's important because renewables are the cheapest option on the market right now and nowhere near done dropping further in price.

If the last ten years are any indication, an order of magnitude further drop in prices before the end of the decade is not unreasonable considering mass production of batteries, solar, and wind is still ramping up and considering the enormous amount of R&D currently being spent on reducing cost and increasing efficiencies further.

In the UK it's going to be hard to compete with wind (Scotland exports more of that than its total energy consumption already) and people installing solar panels on their roof and putting batteries in their house and cars (which can power a house for several days).

Re: Rolls-Royce plans mini nuclear reactors by 2029

#134

Post by scotchmi_st »

dmos62 wrote: post #54
luspr wrote: post #35

Earlier quoted context omitted.

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.

Right but I'm also weary of the kind of second-guessing about the future and the nature of 'progress' that leads to a kind of epistemological paralysis. Taking an approach of 'it's all very complicated, who knows what the future holds, let's not try to plan for it' is also wrong.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#135

Post by radicalbyte »

hokkos wrote: post #119
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.

Why not both ? With cogeneration you raise the efficiency from only electric generation from 40% to 80% with heat, but in summer you can still generate electricity only. And SMR are better positioned than classic reactor because the smaller size and inherent passive security from surface to volume problem (heat raise with volume in power of 3 and cooling only with surface in power of 2) make them easier to build them…

I should have been more nuanced: we shouldn't be building out the current design of fission power in order to decarbonize our electricity production. The biggest reason is that it just takes far too long to build: we're talking 15-20 years. Wind and solar can scale far more quickly than that.

Closing existing nuclear power plants like they're doing in Germany is absolute lunacy.

For heat that timeline is acceptable given that it can be "decarbonized" by switching to burning biomass to cover the transition.

If we could build safe nuclear electric plants within a reasonable timeframe and cost then we should absolutely do it (this would make so much sense in huge countries like the US or China because you can have the reactors located well away from large populations).

Re: Rolls-Royce plans mini nuclear reactors by 2029

#136

Post by Koshkin »

The natural reserve of radioactive material, like that of fossil fuel, is finite. We cannot count on it in the long run. On the other hand, we are awash with the huge amounts of the free solar energy. We just need better batteries, which is a purely technical problem.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#137

Post by Beltiras »

I'm amazed that the industry is still propagating the mistake made in the early nuclear age of using PWR and solid fuel. The more I read about nuclear the more convinced I become that SMRs for next gen plants are safest and most efficient using the Thorium-U233 fuel cycle and employing molten salt to transfer heat. It's automatically safe since if a runaway reaction takes place the fuel will drain into a tank and reactions will stop. This happens if no action is taken so all the humans at the plant and all the machinery could be incapacitated and a meltdown automatically stops. It uses a cheaper fuel of which we have a virtually endless supply of and enrichment is not needed as it is with U238-U235. There's less waste as well and it's less problematic waste (decaying in hundreds of years instead of millions). Operationally it's easier to load up fuel and wastes are easier to remove. Is it just "this is how we always do these things" or is there something else going on here?

Re: Rolls-Royce plans mini nuclear reactors by 2029

#138

Post by Beltiras »

Koshkin wrote: post #136

The natural reserve of radioactive material, like that of fossil fuel, is finite. We cannot count on it in the long run. On the other hand, we are awash with the huge amounts of the free solar energy. We just need better batteries, which is a purely technical problem.

If we moved to Thorium the supply is virtually endless.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#139

Post by ed_balls »

koheripbal wrote: post #117
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.

The best economies of scale comes from building many LARGE reactors - not small ones.

I'm not sure how do you mean. You get economy of scale by saving in costs gained by an increased level of production. It's cheaper to create 100 widgets for 100 small reactors in 10 locations, then for 10 large reactors.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#140

Post by inertiatic »

dsfyu404ed wrote: post #108
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…

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 plent…

Isn't the fact that failure of the transport system would have catastrophic consequences an issue you're concerned with?
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