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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

#111

Post by dsfyu404ed »

rusk wrote: post #74
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…

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…

>We're talking about substances that will remain toxic for thousands of years

Most substances are toxic forever. If you bury mercury or lead in a hole a dig it up in a few million years it will be just as toxic. Radioactive substances are an anomaly in that they become less toxic over time.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#112

Post by DennisP »

nolok wrote: post #66
pferdone wrote: post #28

Earlier quoted context omitted.

TerraPower [1] seem to have a good alternative with its Traveling Wave Reactor. It can be run on nuclear waste we already have and provide energy to 10bln people with US per capita power consumption for basically eternity. [1] https://en.wikipedia.org/wiki/TerraPower

Always be wary of grandiose claims like this that amount as much to facts as to marketing material.

These are well-known properties of any fast reactor, like Terrapower's.

Only about one percent of high-level nuclear waste is fission products, the broken-apart atoms left after fission. The rest is U238, unused U235, plutonium, and other transuranics produced by absorbing neutrons without fissioning. Fast reactors can fission all of these. That's why they can run on nuclear waste.

For the same reason, they can get over a hundred times as much energy from the same amount of uranium ore. Conventional reactors can only use the U235, which is 0.7% of natural uranium.

That's a great start, but with such efficient use, it's practical to get the uranium from seawater. We can do that now at five times the cost of mining; if we only need 1% as much uranium, then total fuel cost would be 5% as much as nuclear reactors spend on fuel today. Fast reactors fueled from seawater would last for millions of years.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#113

Post by p_l »

rusk wrote: post #105
posix_me_less wrote: post #95

Earlier quoted context omitted.

> 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 amou…

Fast reactors can burn waste pretty well, as few other designs. However, it's politically problematic because it involves using plutonium burning (not as fuel, but produced in the reactor while burning down uranium).

This is not liked by certain governments, even if theoretically NPT gives a framework to do it safely, and large scale commercial reprocessing essentially died after India used Canada-built CANDU reactors to kickstart their nuclear weapons program.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#114

Post by koheripbal »

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…

There's also some false equivalency in the quote above. "Environmentalists" is a vague term.

If we asked Environmental Energy SCIENTISTS, they overwhelmingly support nuclear power.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#115

Post by p_l »

rusk wrote: post #74
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…

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…

Fast reactors as well as other specialized designs can burn down fuel that is currently stored as "waste", and just don't produce such long-lived isotopes.

For examples, the half-life of output products from uranium-fueled SVBR-100 is ~550 years, and that can be reduced further by several technologies that are now available.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#116

Post by koheripbal »

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…

Agreed. There are way too many advocates for theoretical solutions.

The reality is that nuclear power, as is, can solve global warming.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#117

Post by koheripbal »

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.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#118

Post by koheripbal »

simonblack wrote: post #17

Nuclear reactors' biggest drawback is the cost and danger of dismantling and disposing of them after their working life is finished. Up till then they are clean and cost-effective.

Why does no one ever factor in the cost of dismantling other major projects, like the Hoover Dam, or the Three Gorges Dam? ...or thee solar plants being built, or the wind turbines?

Why does nuclear power have this enormous additional requirement that literally no other power source seems to have to account for?

Re: Rolls-Royce plans mini nuclear reactors by 2029

#119

Post by hokkos »

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 near populated cities.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#120

Post by koheripbal »

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.

The batteries at the scale needed to provide consistent baseload, simply do not exist and are still entirely theoretical at this point.
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