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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

#311

Post by jhayward »

friendlybus wrote: post #278
WhompingWindows wrote: post #266

Earlier quoted context omitted.

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.

No. France is retiring plants and has a nominal plan to retire 30% of their nuclear generating capacity in the next decade.

There is one plant being built at Flammanville. It is 11 years over schedule and 400% over budget, and still not certain that those will be the final numbers.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#312

Post by belorn »

cygx wrote: post #302
belorn wrote: post #175

Earlier quoted context omitted.

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%).

Since electricitymap gives current say 40% coal and 15% gas, to a total of 55%, I assume fossil fuels are not down to 40% all the time. What you are describing is the average.

Feel free to prove me wrong, but when the wind over Germany is still (<4ms) and its night, the amount of energy production using fossil fuels are higher than 70%, and thus at peak, fossil fueled energy production is higher now then before when nuclear stood for 30%.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#313

Post by jhayward »

stjohnswarts wrote: post #217
Kaibeezy wrote: 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?

I find that to be an incredibly naive statement to any student of mass production. It's not like they won't be tested on a small scale before they start pumping them out. Sure there is a minute chance but this is just fear mongering.

I'll just point out that auto makers who manufacture in the 100's of millions of units often have mandatory, stop-use, stop-sales recalls on their products 5-10 years after sale.

What you are asserting isn't the reality of mass production as experienced by industrial society so far.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#314

Post by wazoox »

fsh wrote: post #205
wazoox wrote: post #177

Earlier quoted context omitted.

No, renewable are incredibly expensive, on the contrary. Why is that? Because renewable produce when wind blows or sun shines, and not when we need power. That's the first point, we need to produce exactly as much energy as we consume, at any time. Renewables fail utterly at that, and that's why renewable energy appears so cheap when you simply consider the price at which it's sold on the markets: production occurs a…

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.

I like that people downvote without providing any argument, any numbers or any source. Slow clap. Enjoy your blackouts.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#315

Post by cygx »

belorn wrote: post #312
cygx wrote: post #302

Earlier quoted context omitted.

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%).

Since electricitymap gives current say 40% coal and 15% gas, to a total of 55%, I assume fossil fuels are not down to 40% all the time. What you are describing is the average. Feel free to prove me wrong, but when the wind over Germany is still (<4ms) and its night, the amount of energy production using fossil fuels are higher than 70%, and thus at peak, fossil fueled energy production is higher now then before when…

and thus at peak, fossil fueled energy production is higher now then before when nuclear stood for 30%

But that's an irrelevant metric: What matters is the total CO2 released, ie the integrated value. So short-term, you replace coal plants by gas peakers, and transition to next-gen storage mechanisms long-term (better batteries, cryogenic storage, power-to-gas - the latter is especially interesting as Germany has pre-existing gas infrastructure than can store hundreds of TWh, and we use natural gas anyway for heating and industrial purposes).

Re: Rolls-Royce plans mini nuclear reactors by 2029

#316

Post by reitzensteinm »

ZeroGravitas wrote: post #282
Accujack wrote: post #216

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.

Do you have any data on power consumption near the equator, or where does this assertion come from?

Anecdotally, it doesn't ring true to me from my time in Thailand and Malaysia, where inefficient air con would be left on in poorly insulated houses overnight to help people sleep. I couldn't find any graphs like you can trivially find for power grids in the west.

But I did find this article[1] which indicates the record power consumption occurred at 9:35pm, beating the previous record which occurred at 10:28pm a few years prior, and both of these are times where it's all going to be coming from batteries.

But this isn't necessarily representative. Even if your reference is a book I'd be happy to purchase it, I find solar penetration in developing countries particularly interesting.

[1] https://www.thaipbsworld.com/power-consumption-in-bangkok-su...

Re: Rolls-Royce plans mini nuclear reactors by 2029

#317

Post by abstractbarista »

uurrnn wrote: post #289
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...

You have to understand that "Lowest deaths per terawatt-hour" is not the sole stat to look at to determine something's danger. I think the flat amount of direct and indirect death, as well as considering the amount of people who's quality of life has diminished, but not enough to kill them. Other energy industries have these problems too, so I have no idea how they actually compare.

Energy sources like coal undoubtedly reduce the quality of life of individuals near the energy source more than nuclear.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#318

Post by fsh »

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…

Your calculation does not make much sense (GWh isn't even a unit of power). One would have to look at actual power production and consumption curves in order to estimate the required storage capacity. Battery storage is still very exotic, pretty much the entire capacity is provided by hydro nowadays.

Current-gen solar panels average about 30 W/m² over the year in Japan's latitude and climate. So a solar park the size of the Fukushima exclusion zone would produce around 7 GW on average which is more than the combined nameplate capacity of the six reactors (5.3 GW). Supplying the entire country with electricity (~114 GW) would require about 3800 km² of solar panels, or about 1% of Japan's area.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#319

Post by cameldrv »

ZeroGravitas wrote: post #277
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...

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.

The point is that it's an extremely safe method of power generation, and what is cited as a key downside is in fact empirically a huge upside to nuclear. No one is demanding retrofit rooftop solar, wind, or gas turbines be shut down on safety grounds, even though they are considerably less safe.

Re: Rolls-Royce plans mini nuclear reactors by 2029

#320

Post by jabl »

DennisP wrote: post #112
nolok wrote: post #66

Earlier quoted context omitted.

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 o…

Breeders and seawater would likely last even longer than that, as U in seawater is in a pseudo-equilibrium, constantly leaching from bedrock.
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