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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

#271

Post by belorn »

eloff wrote: post #226
chrisco255 wrote: post #150

Earlier quoted context omitted.

There's no solar energy in the Sahara at night. And then as people mentioned, there is energy lost in transmission through resistance in power lines. There's also the fact that not too many of the world's 8 billion people live within serviceable range of the Sahara, assuming you can get past the geopolitical instability in that region to construct and maintain such things. The solar cells would need constant cleaning…

Every thread in HN is filled with pessimistic people pointing out how things can't work. It's tiring to read. Solar and wind absolutely can produce all the energy the world currently needs, using only a tiny fraction of available land area. You could power the whole of the US by 100 square miles of solar panels in the southwest, backed with one square mile of batteries [1]. Clearly it's a hard problem and there are m…

You can absolutely power the whole of the US by 100 square miles of solar panels in the southwest. The cost would be to build the solar panels, the square mile of batteries, replace all the power lines in the US with cables that can handle very high voltage (twice or more than what current power transmission cables can handle) needed for long-distance, and replace all the power stations connected to those so that can take that high voltage.

It not impossible at all, we have the technology, it just money. Replacing 200,000 miles of cables, with a price tag of a few millions per mile is a project the US could undertake. Replacing all the power station to handle the very high voltage is similarly possible.

When choosing between the many alternatives it is something which should be calculated next to the cost of building nuclear plants in a distrusted pattern, and the long term cost of nuclear waste that such plan would entail. If entrepreneurs could invent power transmission cables and power stations that can manage millions of volts and cost a fraction of existing methods to install would make a centralized place for power generation a much more attractive option.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#272

Post by pasttense01 »

renaudg wrote: post #190
Brometheus wrote: post #171

Earlier quoted context omitted.

For nuclear you still need to have peaker plants. ALso nuclear is really expensive.

Pretty sure it's actually cheapest per kWh

No. If it were cheapest companies would be building nuclear. Right now in the U.S. the cheapest are wind, natural gas and solar.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#273

Post by big_chungus »

WhompingWindows wrote: post #266
arcticbull wrote: post #255

Earlier quoted context omitted.

> ... 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...

It's not "probably" expensive; it's undeniably very expensive, which is why it's a non-starter in most of the world. Look at South Carolina's fiasco with nuclear...the only country doing nuclear is China, which is known for massive infrastructure spending.

Horror story from a friend who worked in China as a consultant on the power grid back in the mid-aughts. Basically the guy who was leading construction on the plants was working with another who was to supply the concrete for the walls. Problem was, the concrete guy was behind on his "five year plan", so plant guy didn't have enough concrete. Plant guy still has to meet _his_ targets, so he just builds the plants with thinner walls.

Sure it's an anecdote, but the point is China has very loose safety standards and cuts a lot of corners. She's much more okay with losing a few people here and there.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#274

Post by yohannparis »

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.

Easier to say that when you have anything.

Advancing as a species can merely making sure that everyone got a safe environment, freedoms, access to education and health, etc.

There are still billions of people who barely have the quality of life that most of Hacker News reader does.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#275

Post by akiselev »

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…

The solution is to replace the reactor chamber far more often than you would in other reactor designs. It's not actually an insurmountable problem because fluoride chemistry is extremely common in nuclear engineering - most of our nuclear waste is stored as uranium hexafluoride after all - and there is a lot of expertise in dealing with exotic corrosive materials. It's just that replacing your entire reactor every year is astronomically expensive. Just because the technology exists to do it, doesn't mean that it can be done economically when competing against natural gas, solar, and wind.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#276

Post by Retric »

stjohnswarts wrote: post #242
Retric wrote: post #193

Earlier quoted context omitted.

Batteries inherently allow for peaking power, it’s nuclear that has issues with fluctuations in demand. So, by average I mean how much are you able to use directly vs how much do you need to store in batteries. To be more clear only using solar with battery backup you can provide 24/7 power that covers demand but at lower costs per kWh than current nuclear numbers operating 24/7 and vastly lower than trying to reach…

Your argument is completely shot down by the mere fact that 75% of France's power is provided by nuclear energy.

Nope, ~60% of France’s power is provided by nuclear while 71.6% of it’s power production is nuclear. They export 86.3 TWh almost entirely nuclear power and import 26.1 TWh almost entirely non nuclear power (2016).

Even then their nuclear capacity factor is 77% where it’s generally 90+% in the US because frequently nobody want’s to import electricity from France. So, France’s high percentage of nuclear power results roughly 17% higher costs per kWh for nuclear power due to oversupply. Or more depending on what it exports at.

Further, the more you increase nuclear capacity globally, the less anyone is going to be importing it at night and weekends when everyone is over supplied.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#277

Post by ZeroGravitas »

arcticbull wrote: post #255
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...

Your lowest death stats seem to be missing grid scale solar and rooftop solar that isn't a refit.

Which is extra significant if it's also the cheapest.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#278

Post by friendlybus »

WhompingWindows wrote: post #266
arcticbull wrote: post #255

Earlier quoted context omitted.

> ... 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...

It's not "probably" expensive; it's undeniably very expensive, which is why it's a non-starter in most of the world. Look at South Carolina's fiasco with nuclear...the only country doing nuclear is China, which is known for massive infrastructure spending.

France? 70% nuclear power and growing.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#279

Post by lukifer »

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.

On the one hand, limitless growth is an unsustainable anti-pattern (when it manifests in the biological realm, we call it cancer).

On the other hand, it's hard to see how civilization could continue to function without the prospect of "growing the pie". If/when we reach a steady state of finite resources, it seems highly likely that the best strategy (individually and tribally) is acquire resources at the expense of one's neighbors (before they acquire your resources first). This has been the default state of nature for nearly all biological history, with occasional exceptions of growth and plenty.

I don't have an answer here, long-term; and where the rubber meets the road, I do think our corporate model of "your business is failing if it's not growing" results in more negative than positive externalities (at least, beyond a certain equilibrium), and should be eyed critically. But the growth model is as much about social mindset as it is real-world wealth generation; and luckily we have lots more progress we can make (both on and off Terra Firma) before we're at risk of fully diminished returns on the growth of sentient well-being. The question is one of intelligent growth (cue Bucky Fuller [0]), rather than a locust-like runaway replicator pattern, which is clearly net-negative even if it looks like growth when zoomed in.

[0] https://en.wikipedia.org/wiki/Operating_Manual_for_Spaceship...

Re: Rolls-Royce plans mini nuclear reactors by 2029

#280

Post by [deleted] »

wazoox wrote: post #267
fsh wrote: post #205

Earlier quoted context omitted.

Do you have any sources for your claim of batteries multiplying the cost for renewables by "5, 10 or more" in a realistic grid scenario? Did you take into account that most energy storage is done with hydro, not batteries? I haven't had time to carefully review the literature, but there seem to be quite a few papers that claim that storage for a 100% renewable grid would not be such a big issue.

Basically renewables produce 15-20% of the time (30 to 40% for offshore wind). Let's be generous and start with 30% of the time. You need storage to provide 70% of the demand. So for every GWh or required power, you need 700MWh of storage. The famed Tesla Mega battery is a puny 129MWh... You must account for the fact that there could be no sun or no wind for several days, therefore be able to store incredible amounts…

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