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Nuclear power: Are we too anxious about the risks of radiation?

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Re: Nuclear power: Are we too anxious about the risks of radiation?

#441

Post by littlestymaar »

ovi256 wrote: post #371
littlestymaar wrote: post #84

Earlier quoted context omitted.

> Everything around the nuclear disasters has been a human bullshit of a problem, not a technological one. Probably with the exception of Fukushima, where all the conditions were put into the extreme - killer earthquake and monster tsunami. In fact, even Fukushima there were human (stupid) mistakes: - the levee was too low, and the regulator told TEPCO they needed to improve it (which they didn't). Interestingly enou…

>CPNE de Nogent sur Seine suffered a critical failure, Paris and the entire Île-de-France region, which concentrate most of the French economic power, would need to be evacuated Why ? Paris is as far from Nogent NPP (89 km) as Kiev is from Chernobyl NPP, so there's plenty of space to setup an exclusion zone, even in the worst case scenario of an open core meltdown (which are much less probable with Western PWR design…

> Why ? Paris is as far from Nogent NPP (89 km) as Kiev is from Chernobyl NPP, so there's plenty of space to setup an exclusion zone, even in the worst case scenario of an open core meltdown (which are much less probable with Western PWR designs).

You stopped halfway through in your reasoning: a PWR reactor is less prone to reactor meltdown than an RBMK one, AND the consequences would be different.

Because there's no graphite, there would be no fire, then the radioactive dust cloud would be almost nonexistent. What would happen instead would probably be a Fukushima-like scenario, where tons of contaminated water would end up in the environment. But this time, the environment wouldn't be the gigantic Pacific Ocean, but the Seine river… which crosses Paris and is a major supplier of freshwater for the whole urban area.

You really don't want a catastrophic failure at Nogent!

(You'd have the same issue with CNPE du Bugey and the city of Lyon btw).

Re: Nuclear power: Are we too anxious about the risks of radiation?

#442

Post by bosie »

adrianN wrote: post #384
Manfredo_1 wrote: post #334

Earlier quoted context omitted.

You use the word "smart grid" as though it just automatically makes electricity usage go down. A smart grid works by redistributing load to when there is power. A smart grid almost always needs storage, unless it's doing simple things like running your dryer where it's just a matter of turning on your appliances at a certain time of day. If you're at he from 7pm to 8am, and you want your home to be heated while you'r…

I use "smart grid" to mean that the electricity provider has a measure of control over the load. For example they can turn heating in your home on or off as long as the temperature stays within a band defined by you. This is not science fiction, it exists today. I know people who use it already.

How much can the provider shave off the load though? if i set my band between 21 and 23 degrees, is the reduction more than a few percent max? Doesn't seem to make a dent given the peak requirement when the majority of the people all shift locations (i.e. go home)?

Re: Nuclear power: Are we too anxious about the risks of radiation?

#443

Post by GekkePrutser »

avar wrote: post #368
Aachen wrote: post #305

Earlier quoted context omitted.

1. It's slightly less than 2x, not 10x. 2. Countries like the Netherlands that don't have the space for sufficient on-shore wind have to go to off-shore wind, which is actually more expensive than nuclear energy. 3. We'd be making actual progress instead of fighting residents and nature preservation for every plot of land again and again, auctioning land leases for every few megawatts, and it all just taking forever…

The Netherlands has plenty of space for on-shore wind, what it doesn't have is sufficient space for them to get away from the NIMBY's. Hence building them off-shore.

Off-shore is of course a great way to have the benefits without the drawbacks. The Netherlands is quite full already and we should be careful with the small amounts of nature we have left. The added cost isn't a huge thing when your factor in it's clean energy without long term waste like nuclear.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#444

Post by skrause »

swilliamsio wrote: post #438
namanaggarwal wrote: post #429

Earlier quoted context omitted.

Totally unrelated but why the land of rising sun (cannot go east than that) is being called a western nation.

Western as in democratic, high income, economically prosperous, broadly supportive of human rights, etc.

A better term for that is "developed country".

Re: Nuclear power: Are we too anxious about the risks of radiation?

#445

Post by GekkePrutser »

AI_WAIFU wrote: post #180
p1mrx wrote: post #119

I think the most legitimate concern about nuclear safety is, what happens to the plant if you push the "OFF" button and go home? The current gigawatt-scale plants (AP1000, Hualong One, etc.) can cool without external water for 72 hours, after which a meltdown occurs. NuScale plans to run their reactors at the bottom of a pool, with enough water to passively transition to air cooling over the course of a month. (There…

I don't understand who's bright idea it was to use water as the primary coolant for a nuclear reactor. IIRC almost every single major nuclear incident has been caused or dramatically exacerbated by having it boil away or cause a steam explosion or mix with the ground water or chemically react with the fuel rods to produce additional heat and hydrogen gas which also explodes. Like just go through this list and count t…

Liquid metal reactors also have had their fair share of accidents despite their small presence.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#446

Post by speeder »

dboreham wrote: post #434
gtsteve wrote: post #426

Earlier quoted context omitted.

> of course a lot improved after Chernobyl in terms of reactor safety My understanding is that Chernobyl was caused by an experiment that went wrong due to errors in following processes correctly. I would assume that most reactors just make electricity, and outside of smaller reactors used for research they aren't used for experiments. Is that correct?

Not an expert but my understanding is that you are largely incorrect. The "experiment" was a test the facility had to pass (dark station shutdown) in order to be certified safe. The site's primary function was to generate electricity. Secondary function to create weapons material precursors. That humans had to follow processes in order to avoid contaminating large parts of Europe is a fundamental failing.

Kinda.

Dark Station shutdown is still a problem in some senses.

They were indeed, doing an experiment, not just to pass a certification, but they were testing a theory, that in fact makes perfect sense, just the execution of the test was extremely crap.

The problem: when the power grid fails, there is no power to keep the coolant system pumps working, thus might cause a meltdown.

Chernobyl solution: attempt to improve the turbine designs so they can keep generating power using their own inertia until the diesel generators are online.

Chernobyl first failed attempts: improvements were not enough, the idea DID worked, but the turbines stopped spinning too early.

Chernobyl last attempt: power usage in the day of the test was unusually high, not only the test was delayed but the reactor had to produce more power than usual, when the test finally came, the procedures of the test weren't followed properly, the crew that did the test didn't knew how to do it, and after they pushed the reactor parameters to values outside the design limits, the computer attempted to fight back, so they disabled the safety features of the computer and tried to control the situation manually, doing things the computer was requesting them to NOT do.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#447

Post by sokoloff »

jakehop wrote: post #416
swilliamsio wrote: post #395

Earlier quoted context omitted.

"What about Chernobyl" is usually outright dismissed as being an edge case owing its disaster to the Soviet regime, more concerned over image than safety. The real important question, as you aluded to, is "What about Fukushima" - a disaster occuring in a rich, western nation, Japan; Japan is a nation generally seen as being on the leading edge of technology. If a disaster can occur in Japan, it can feasibly happen an…

Of course the probability is never 0,00%. But it is obvious that the Fukushima accident happened due to geological factors. The same power plant would hum away nicely in Germany to this day, where there is little to no seismic activity and none on the scale of what happened in Fukushima.

Were the builders of Fukushima unaware of the geology of Japan?

I would argue that they were aware and still got hit by the risk. I don’t see “well, that specific failure won’t be what gets us in Germany” as especially compelling.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#448

Post by GekkePrutser »

pfdietz wrote: post #162
p1mrx wrote: post #142

Earlier quoted context omitted.

The challenge is just having enough raw capacity to meet demand using intermittent renewable sources. Weather varies on the scale of days/weeks, and winter is cold because of limited sunlight. What energy source will we use to stay warm all winter?

Make hydrogen, store it underground, and have enough combustion turbines available to back up the grid. A simple cycle combustion turbine power plant is about 5% of the cost of a nuclear power plant, per unit of power output.

Making hydrogen via electrolysis is very lossy though.. it's only worth it if you have nothing else to burn the power on.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#449

Post by jakehop »

jerven wrote: post #352
Manfredo_1 wrote: post #266

Earlier quoted context omitted.

> A battery for 100/kwh can be used several 100 to 1000s of cycles. You're making the same error as reitzensteinm. The fact that you can charge and discharge a 1 KWh battery a thousand times doesn't make it a 1 MWh battery. If the United States wants to use 80% renewables we need 12 hours of energy storage, which works out to 6 TWh. Even at a very generous cost estimate of $100/KWh, this works out to 600 billion doll…

600 billion = +/- overnight cost of 30 nuclear powerplants (AP-1000). And would struggle with providing 500Gw that the battery above could. At that scale everything is expensive, but the market still seems to say that Nuclear is more expensive than the other options. My hand-wavy maths aside, the people who sign the checks seem to agree that today (2020, it is cheaper to get power from solar/wind + battery than nucle…

The battery isn't the source of the energy. You are missing wind and solar (which isn't free), an electrical grid overdesigned for the peak-energy requirements (since you will not get all of your energy over the course of a day).

4 APR-1400 will cost the UAE ~ $24.4 bn to complete. So $600 bn will give you 98 APR-1400 reactors, for a total of 131GW of electrical power – not to mention twice that in thermal power, which can be used for central heating, hydrogen production, etc.

This thermal energy is currently ignored in almost all calculations; it makes little sense to include it in a debate that only focuses on electricity, but at the same time it makes little sense to have such a debate (unless one is a lobbyist), when the use-case is much broader.

The most expensive part of nuclear energy are the capital costs – the discount rate in particular – since it is a "everything up front"-project, where political scrutiny is extremely high (much of it for good reason, but too much is mainly the 'vetocracy' and NIMBYism in action) and the low amount of new plants being built is limiting the build-up of knowledge.

In my native country of Denmark, there is basically zero research in nuclear compared to other energy sources; even in the institutions that were led or founded by the Nobel-prize winning Danish physicist, Niels Bohr. That is all due to politics and it shifts the debate to be less and less about science, which is one of the saddest things to happen.

Re: Nuclear power: Are we too anxious about the risks of radiation?

#450

Post by bedosh »

teraku wrote: post #306
emteycz wrote: post #285

Earlier quoted context omitted.

Are you sure it was $15/MWh? That seems more than 1000x cheaper than state of the art batteries.

I just checked some prices for small scale PV farms you can plant to your house. It's 16,83 euro-cent for the PV per KWH and 23,74 euro-cent for the storage. Production is 10KWH, storage is 11KWH. So if we (naively) multiply by 1000 we get 23,74€/MWh. And that is for the home market. I know battery storage doesn't scale linearly, but also if you were to build this as a highly-scaled farm, I'm sure prices would also d…

23 euro cents * 1000 is 230 Euros, not 23. But that is still a factor of 1000 lower then the prices mentioned in https://www.nrel.gov/docs/fy19osti/73222.pdf and other web publications. Are you sure about those numbers and what kind of storage do they refer to?
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