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Rolls-Royce plans mini nuclear reactors by 2029

bbc.co.uk

301–310 of 353 posts

Re: Rolls-Royce plans mini nuclear reactors by 2029

#301

Earlier quoted context omitted.

That technology is far more expensive than photovoltaic panels.... for example, the solar thermal Ivanpah project is now obsolete for that exact reason. Additionally, The storage density of molten salt is far lower than the generation capacity of a reactor.

Solar plus battery near the equator can be sized for 24/7 power with relative ease. But no one would do that, because we don't need power at the same rate all the time. Near the equator, where most people on the planet live, our need for energy is correlated with when the sun is shining and air con is running and people are awake. This is why solar is better even at the mythical "baseload" than nuclear is.

>Near the equator, where most people on the planet live

Nope.

In fact, a minority of people live near the equator... for good reason:

https://www.datagraver.com/case/world-population-distributio...

Also, the base load most of us are talking about isn't created by people for the most part... it's created by industry, without which life on the equator or anywhere else would be rather primitive.

In any case, the equator is going to become unlivable in the next few decades to the point where populations in equatorial areas will drop drastically.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#302
post #175
post #142

Earlier quoted context omitted.

Countries which currently are replacing nuclear power do so with a combination of renewables and fossil fuels Which countries? Germany for example isn't - yet. We're still in a place where we can reduce usage of both fossil fuels and nuclear, though that won't last unless we figure out effective means of energy storage.

As an example, Sweden. People will use fossil fueled energy when the choice is between people freezing in their home or burning fossil fuels. Sweden rely on a mix between hydro and nuclear, but it is not feasible to extend hydro beyond current capacity. The nuclear plants however is getting older, and politically people want to shut them down. Something has to produce the energy, and during the winter it is imported…

Sure. But that doesn't make Germany an example of replacing nuclear with fossil fuels. From 2002 to 2019, percentage wise, fossil fuels went down by 1/3 (from ~60% to ~40%) and nuclear by 1/2 (from ~30% to ~15%).

Re: Rolls-Royce plans mini nuclear reactors by 2029

#303

>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...

I've actually wondered if we could find enough suicidal idiots maintain the growing number of wind farms.

Finding climbers for static towers is already hard enough. Death rates of cell tower climbers are 10x that of normal construction workers (cell tower climbers have the highest death of all construction jobs). Of all those deaths investigated by OSHA, almost 40% involved no rules violations -- speaking of that, only 3 of those found in violation were fined more than about $25,000 with most being fined less than 10k and some only being fined a few hundred dollars).

Unlike static cell towers towers, you have lots of moving parts you can't really stop and high-voltage power sources you can't completely shut down. There's additional risks of fires and even disintegrations.

Unlike cell towers, I can't find any overall statistics. The closest I can find is [this organization](http://www.caithnesswindfarms.co.uk/AccidentStatistics.htm). It's crazy to realize that at least one windmill suffers structural failure every month. Two catch fire and (since there's currently no way to put out a fire hundreds of feet in the air) burns down. Two more will suffer blade failures whipping sections of blade out at up to 325km/hr (200mph). There will even be someone who is injured due to ice being flung by the blades and hitting someone over 150 meters away. This is all before counting the couple people killed every month. And to top it all off, they don't even have complete statistics.

Underwriters Lab (the official unofficial US government lab) in 2015 claimed a 0.54% blade failure rate worldwide, but with almost 500K units, that's still thousands of units every year (I'd note that they don't actually have reliable data on the 42% of all wind turbines that happen to be located in China). [source](https://www.enr.com/articles/42352-are-four-wind-turbine-fai...)

To quote another [article](https://www.power-technology.com/features/golden-hour-parame...)

> There were 737 reported incidents on UK offshore windfarms in 2016; blades falling off, turbines tipping over, falls from height, vessels sinking in ice-cold water, groundings, onboard fires, helicopter crashes make up just some of the reports. The most common accounts were of hand injuries, while fingers cut off, arms crushed, broken bones, fractures, lifting injuries and teeth knocked out also occur. Non-accidental medical emergencies include strokes, heart and asthma attacks, and anaphylactic shock.

> Of all the incidents at UK offshore windfarms, the majority happened on operational sites: only two were recorded during windfarm development in 2016. Around 44% of offshore medical emergencies occurred in the turbine region, while just over one quarter were on vessels. The number of fall-related injuries was 110 or 15%, of which 95 (13%) were during heavy lifting operations.

Then there's the issue that wind turbines seem to have a realistic lifespan of only 12-15 years instead of the 20-25 years claimed and lose half of their total power output over that 15 years. [source](https://www.telegraph.co.uk/news/earth/energy/windpower/9770...).

Solar panels have a relatively low direct body count, but mining then melting down entire mountains for their rare earth elements has a severe environmental impact (not to mention the environmental toxins and toxic waste produced during the actual manufacturing process).

In the entire existence of US nuclear power, there have only been around 60 incidents which resulted in death or damages over $50,000 (and only 13 deaths overall) and unlike wind power, every little thing about nuclear plants is logged thoroughly. Even the "waste" is safer to store on average than the caustic waste from manufacturing and will be refined and reused once cheap mining sources dry up.

Rather than scaring everyone with nuclear FUD, we need to embrace it as the most promising and safest green energy technology we have.

EDIT: I'd also give a shoutout to concentrated solar which could be a great green daytime alternative with some caveats (variable power output, still needs nuclear power at night, much more geographically limited, etc).

Re: Rolls-Royce plans mini nuclear reactors by 2029

#304

Earlier quoted context omitted.

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.

There's communication cables laid across the sea. There's no examples I know of High Voltage transmission with enough power to operate Europe. It's not only the instability of Sahara, but laying a cable across the sea for the transmission of enough energy to power Europe would require defense of the cables. A submarine could otherwise attack the grid and take Europe offline. This is unpractical on a lot of levels and…

So your point is exactly my point?

The technology isn't a problem. Superconductors wouldn't solve anything. It is a political problem.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#305

Earlier quoted context omitted.

Solar power in the desert produces power 24/7 by keeping the molten sand hot overnight. It’s also always sunny

That technology is far more expensive than photovoltaic panels.... for example, the solar thermal Ivanpah project is now obsolete for that exact reason. Additionally, The storage density of molten salt is far lower than the generation capacity of a reactor.

Solar panels may be cheap to produce, but they are terrible for the environment because of the complex manufacturing process. Parabolic reflectors can be melted down and reformed without huge additional environmental costs. If you're interested in the environment, this is the real benefit.

Cutting-edge solar panels have about 23% theoretical efficiency. Stirling dish systems have about a 30% theoretical efficiency and about a 25% real-world efficiency.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#306
post #74

Earlier quoted context omitted.

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.

To be fair, many substances in the nuclear industry, including the fuel, are quite toxic even chemically.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#307

Earlier quoted context omitted.

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.

You're kind of getting at my point, at 0 resistance you can route around any of these problems. A planet wide mesh is just logistics at that point.

Semiconductors don't have infinite capacity. You assume that the superconductor is also practically free. Even them, building a net is still very expensive

Re: Rolls-Royce plans mini nuclear reactors by 2029

#308

Earlier quoted context omitted.

Stellar fusion like that which occurs in our sun is effectively aneutronic, but is also relatively slow, because the limiting step is the combination of two protons into a proton-neutron pair. You need to keep a lot of hydrogen at plasma-hot temperatures and very high pressures for a long time. So you can't really do it with masses smaller than Jupiter, because smaller bodies can radiate the energy away faster, and p…

Aneutronic reactors are good of course, but the Sun still puts out lots of other dangerous radiation. In particular, ultraviolet electromagnetic radiation from the Sun causes tens of thousands of cancer deaths every year. I have no problem accepting a few percent of that mortality from man-made radiation sources if that helps solving the CO2 emission crisis.

Good. For the foreseeable future, the limit of energy available from solar will be the total surface area of the Earth divided by two.

And that includes hydro from evaporation-rainfall cycling, photosynthesis, and wind. Which basically leaves as alternate energy sources tidal, from the sun and moon dragging the oceans around, energy stored from long periods of solar absorption in ages past, residual geothermal, and nuclear.

A little neutron-activated waste is indeed a small price to pay.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#309
post #47
post #2

"Production line mistakes may lead to generic defects that propagate throughout an entire fleet of reactors and are costly to fix," (person from University College London) warned. Wouldn’t the knowledge gained by fixing a large one-off reactor be of limited transferable value, as compared to expensive knowledge that could be used to upgrade an existing “fleet” plus improve subsequent versions?

Having to fix it at all is a serious problem. France is currently dealing with reactor fleet problems: https://www.powermag.com/frances-nuclear-storm-many-power-pl... ("carbon segregation"), https://www.energy-reporters.com/industry/edf-admits-to-reac... ("welding issues"). In both cases they took a long time to come to light and the country is now stuck dealing with them across a large fraction of its power producti…

I mean without mass production it also means you're dealing with new mistakes every time you create a new reactor.

This idea that mass production creates more mistakes really doesn't make sense when you actually think about it.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#310
post #3
post #2

"Production line mistakes may lead to generic defects that propagate throughout an entire fleet of reactors and are costly to fix," (person from University College London) warned. Wouldn’t the knowledge gained by fixing a large one-off reactor be of limited transferable value, as compared to expensive knowledge that could be used to upgrade an existing “fleet” plus improve subsequent versions?

The point is that every mistake propagated over 10 reactors has to be fixed 10 times. If you have a single reactor, you just fix it once.

It also means each time you create a new reactor, you never learn from past mistakes. Thinking that mass production causes more mistakes makes no sense when you actually think about it.

Cars/guns/airplanes/even furniture all benefit from mass production to keep costs and mistakes down. There's no reason why reactors would be magically exempt from it.

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