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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

#251

Post by lhopki01 »

Accujack wrote: post #218
The_Double wrote: post #197

Earlier quoted context omitted.

Not every country has access to a desert to deploy large scale solar. Most of the EU, Russia for instance, and those places do not want to be dependent on other countries.

It's probably also worth noting that photovoltaics have to be exposed to the sun to work... which means that they can't be protected by armor or bunkers, which means that they're terrifically vulnerable to terrorist or other attack.

The terrorist attack that is going to take out 1000s of square kilometres of solar panels? Surely they'd just attack a city if they had that amount of firepower? Or in the more likely case that they don't it's easier to attack power transmission than generation.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#252

Post by ryacko »

papreclip wrote: post #234
AtlasLion wrote: post #26

Earlier quoted context omitted.

baby steps I'd say. Let's first fix all the mess we are making here on earth before thinking of space exploration.

I think space colonization is an even bigger fantasy than relying on "future tech" that will magically terraform the earth and reverse climate change. We can have a tiny structure housing 10 or 20 people somewhere in our solar system for the price of millions of pounds of fuel and billions of dollars. Inter-system travel will never happen. Forums like this tend to have a healthy population of the sci-fi minded, so it…

Space colonization is only viable for a small handful of people who produce at least a million dollars in revenue per year.

Programmers and CEOs.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#253

Post by ed_balls »

Nasrudith wrote: post #185
ed_balls wrote: post #139

Earlier quoted context omitted.

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.

The efficency also scales with size in this case - separate from the per unit production scale. It is still cheaper and more efficient to have a 1.2 GW diesel power plant instead of a warehouse of thousands of back up generators wired together.

I disagree. If one generator fails, it's not a big problem. If you have a failure in a large reactor it's a biggie, so you have to use very expensive materials and design to avoid failure.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#254

Post by macspoofing »

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…

Wind and Solar need battery backup. There is no grid-scale battery technology today, nor is one forthcoming in any sort of reasonable term (on the order of the next one or two decades). Care to rethink your standard on what is proven and unproven?

Re: Rolls-Royce plans mini nuclear reactors by 2029

#255

Post by arcticbull »

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…

> ... with some maintaining it is dangerous and expensive

Expensive, probably. Dangerous? Not according to the data. Lowest deaths per terawatt-hour of any energy source including solar. Yes, even if you count Chernobyl, Fukushima (where 6 folks died) and Three Mile Island (nobody died) [1]

[1] https://www.nextbigfuture.com/2011/03/deaths-per-twh-by-ener...

Re: Rolls-Royce plans mini nuclear reactors by 2029

#256

Post by xorfish »

chrisco255 wrote: post #223
xorfish wrote: post #191

Earlier quoted context omitted.

HVDC is already below 3% per 1'000km. So connecting Europe to the Sahara is around 5% with current technology

No. Sorry the Mediterranean Sea separates Europe from Sahara (as well as several countries) and you can't do this practically by any means. Europe doesn't own the Sahara.

The main problem with installing solar in the Sahara and transporting it to Europe is the political instability of the region. Laying cables across a sea or ocean is already routinely done.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#257

Post by victorfriedrich »

DrNuke wrote: post #158
Beltiras wrote: post #137

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 rea…

> Is it just "this is how we always do these things" or is there something else going on here? That tech is known, well designed, approved and extensively proven through many thousand years manwork experience worldwide. It’s also the most affordable in liberalized markets. Going smaller & modular is the real novelty in the industry, for grid-agnostic coupling and decoupling. FYI: I have been consulting and designing…

Hearing about the thorium fuel cycle for the first time – would you say that this article from 2012 is still up to date?

https://www.forbes.com/sites/energysource/2012/02/16/the-thi...

Re: Rolls-Royce plans mini nuclear reactors by 2029

#258

Post by cesarb »

scotradamus wrote: post #227
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.

Energy production really isn't the issue. Energy storage is. We produce way more energy than we use. We currently do not have an easy way to store it. So why generate more than we need? Well, we need to have power available to prevent brown outs, especially right after work when everyone gets home and flips their light switch (so to speak). Second; it is actually more efficient to keep the generators fully spun up.

> We produce way more energy than we use. [...] So why generate more than we need? Well, we need to have power available to prevent brown outs

That's not how it works. If you generate more than you need, you will have the opposite of a brown out (overvoltage and/or overfrequency). Generation and consumption of power have to always be precisely matched.

> especially right after work when everyone gets home and flips their light switch (so to speak).

When everyone gets home and flips their light switch, the extra demand slightly reduces the system voltage and frequency; feedback loops on the power plants then increase their generation to match the extra demand.

> Second; it is actually more efficient to keep the generators fully spun up.

Keeping the generators running at their maximum means you have no margin for extra demand or sudden loss of generation (for instance, another power plant or a transmission line having an issue and shutting down). It's better to keep the generators running below the maximum to have a reserve for when these things happen.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#259

Post by kmano8 »

Stratoscope wrote: post #40
brnt wrote: post #32

Earlier quoted context omitted.

I remember Toshiba having a decay-based laptop battery in development (at least 10 years ago, maybe 20). You wouldn't have to charge, ever. Now that would be something!

When I was five or so, I had a watch with a radium dial. I read in a kid's science book that if you went to bed and waited until your eyes were adjusted to the dark, and then held the watch dial against your closed eyelid, you would be able to see the sparks as individual radium atoms decayed. I did this, and it worked! I could see each spark!

Ball watches use Tritium in glass tubes for some really incredible lume https://shop.ballwatch.ch/en/

Re: Rolls-Royce plans mini nuclear reactors by 2029

#260

Post by Someone »

kerkeslager wrote: post #246
akiselev wrote: post #187

Earlier quoted context omitted.

A radioactive fluoride salt might just be one of the most corrosive substances on the planet. Titanium might hold up a little longer but not by much. Any material that can resist the corrosion will be bombarded by neutrons until it is transmuted into another material that can't, even with "slow" neutrons.

Okay, what's the solution? The Wikipedia article[1] says, "A 2011 MIT study concluded that although there is little in the way of barriers to a thorium fuel cycle , with current or near term light-water reactor designs there is also little incentive for any significant market penetration to occur. As such they conclude there is little chance of thorium cycles replacing conventional uranium cycles in the current nucle…

”I can only imagine some sort of mag-lev design that keeps the molten salt out of contact with other materials”

If you were to build that, how would you transfer the heat out of the molten salt?

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