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

bbc.com

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

#431

Post by macspoofing »

pfdietz wrote: post #411
macspoofing wrote: post #350

Earlier quoted context omitted.

> solar + storage providing power evenly over 24h (an unrealistic worst case) becomes economical. That's not the the worst case. Solar output varies by season. So you have to have enough storage for multiple weeks. This also means you have to greatly over-provison solar panels so that they not only provide power, but also enough to charge batteries.

Very rare long term outages would not be covered by batteries. For that, you want a rock bottom low capital cost, even if it's much less efficient. Hydrogen makes sense for that use case, burned in turbines. For seasonal variation, simply overbuilding is also a possibility. No storage would be needed at all in Minnesota, for example, until renewables get to 70% of consumed electrical energy.

>Hydrogen makes sense for that use case, burned in turbines.

And where's hydrogen going to come from? You need to overprovision renewables so that they not only provide power for now, but also store enough power (via batteries or hydrogen or whatever) to get around daily, seasonal and inter-seasonal variability.

And by the way, hydrogen from renewables is massively inefficient.

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

#432

Post by Aachen »

nicoburns wrote: post #362
Aachen wrote: post #336

Earlier quoted context omitted.

Yes renewables have gotten cheaper but nuclear isn't outlandishly expensive either. If it doesn't match expectations and the price doesn't significantly drop further from today (seems unlikely), going nuclear would be a good decision. If renewable continues to drop, we have a bit more expensive power depending on the percentage of nuclear to renewable power. However, if we don't build nuclear, I'm really not sure how…

> However, if we don't build nuclear, I'm really not sure how much CO2 we're adding to the air and how many more people had to die from pollution before we managed to build enough renewables To me the achilles heel in this scheme is how long it takes to build a new nuclear power station. This article [0] says that modern nuclear plants are planned to be built in 5 years (this assumes no time overruns which have been…

I'm aware of the building time unfortunately (10-15 years iirc, seems to match what you wrote), but yeah I'm still expecting it'll be helpful to at least plan for a third, maybe half the power to come from nuclear plants. It's not as if we are likely to be using less energy than today, and on top of that we need a tenfold amount as we use today to replace the petajoules currently coming from oil (e.g. for transportation, I don't know the exact uses, just that NL in 2014 used 10x more kWh or mtoe than we produce+import in electrical power).

Looking at how much renewable power we managed to build in the past ten years, we need to ramp it up massively, while at the same time we just did the low hanging fruit in terms of where to build. A video I watched a few days ago mentioned that Germany had been debating over laws regarding the placement of wind turbines. Germany, the big country (to me), where there is still a lot of nature and space (compared to where I'm from, the Netherlands, here I can find a big forest not far from home and housing is also cheaper due to lower demand for the space). Apparently they were debating over a 1000 meter minimum distance between dwellings and a wind turbine for noise reasons, but that would apparently already have left nearly no space. Now it's 300 meters but some states have higher distance requirements and so you see few turbines there. It's a real pickle...

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

#433

Post by pfdietz »

macspoofing wrote: post #431
pfdietz wrote: post #411

Earlier quoted context omitted.

Very rare long term outages would not be covered by batteries. For that, you want a rock bottom low capital cost, even if it's much less efficient. Hydrogen makes sense for that use case, burned in turbines. For seasonal variation, simply overbuilding is also a possibility. No storage would be needed at all in Minnesota, for example, until renewables get to 70% of consumed electrical energy.

>Hydrogen makes sense for that use case, burned in turbines. And where's hydrogen going to come from? You need to overprovision renewables so that they not only provide power for now, but also store enough power (via batteries or hydrogen or whatever) to get around daily, seasonal and inter-seasonal variability. And by the way, hydrogen from renewables is massively inefficient.

It would come from electrolysis of water, using renewable energy when that's in oversupply.

Overprovisioning renewables for immediate consumption works in tandem with hydrogen, since it means there will be times excess power is available to make the hydrogen.

The round trip efficiency of power->hydrogen->power through turbines will be maybe 33%. But this is FINE, if the capital cost of storing hydrogen in underground caverns is low enough and renewables are otherwise cheap enough (low LCoE).

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

#434

Post by dboreham »

gtsteve wrote: post #426
atoav wrote: post #399

Earlier quoted context omitted.

Well well. My girlfriends oldest brother died in what was a wave of cancer infant deaths that strangely coincides with the fallout of Chernobyl's radioactive cloud. Her other brother came to the world deformed, which again happened to more mothers than hers. In my school class (~30 kids) alone there were 4 kids who had deformations or other mutations that affected their life's negatively (for those who still live: to…

> 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.

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

#435

Post by extropy »

VBprogrammer wrote: post #354
jillesvangurp wrote: post #319

Earlier quoted context omitted.

I just read the news in the energy market. I think California just ordered a few MwH of battery from Tesla. They seem to be doing a brisk business of selling batteries to grid providers in a market that is entirely supply limited. There are loads of companies working on alternate storage technologies. You are right that there is very little right now. But I'd counter that that is growing rapidly and that that is insp…

For grid stabilization in the UK we already have 28GWh of pumped hydro storage. I'm not an expert in sizing grid infrastructure but I expect we'd need storage of several times that to balance a less dispatchable grid. The sun is always shining somewhere doesn't work for day / night solar production. Transmission losses are of the order of 0.5% per 100km. By the time you transmit power 20,000km there is nothing left.

Its Also building enough battery capacity to offset the night is doable. UK annual consumption is around 300TWH, let's round to 1TWH a day.

The nighttime consumption is about half of the daytime's so only 33% needs to be saved.

So we need 350GWH of batteries. It will take a while, cost 35 Billion assuming 100 usd for 1 kwh. Or 2 billion a year or 0.6 cents per KWH of energy consumed.

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

#436

Post by belorn »

rgbrenner wrote: post #169
ComputerGuru wrote: post #125

Earlier quoted context omitted.

Nuclear is only so relatively expensive because it’s the only fuel source that’s forced to pay up for all the externalities up front (and I’m not saying that is a bad thing to require). A nuclear plant can’t be built if the money to make it safe (as per some specification), insure against all health complications while it’s in operation, decommission it, clean up the site, securely dump all spent fuel, and return the…

Your post conveniently ignores solar/wind + batteries, which is even cheaper than coal.

If solar/wind + batteries is cheaper than coal, why are new fossil fueled plants being built at a speed of about 10x capacity for every watt of renewable energy? Are people just bad at investments?

If I was an investor and I would choose something that has lower cost and higher profits, especially if it also favored political. Lower costs and higher profits are pretty nice. Choosing something that cost more and has less profits sounds terrible.

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

#437

Post by GekkePrutser »

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.

But unforeseen factors are always a component of accidents. Otherwise it wouldn't be an accident. Of course boost is planning for this to happen.

The point is that it does happen despite planning. It won't happen in the same way in Germany but something else can happen.

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

#438

Post by swilliamsio »

namanaggarwal wrote: post #429
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…

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.

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

#439

Post by jojobas »

DoctorOetker wrote: post #338
jojobas wrote: post #227

Earlier quoted context omitted.

Some 70 cm. That's right, about half of diameter of these cylinders are concrete walls. For comparison, Schwerer Gustav shells weighed about the same as A380 engine, were mostly hardened solid steel, arrived on target at about Mach 2 and could penetrate some 7 meters of concrete (including the explosive charge). You can help yourself to a F-4 vs concrete test that doesn't really make a dent in about 1m of concrete.

From that video (F4 vs concrete), the narrator who was present at the test says that ultimately its the energy that counts (wheither you model a detailed plane colliding, or a simple sausage shape of same mass and velocity, turns out you get essentially the same result). So let's calculate the kinetic energy for the 3 things mentioned: the Phantom F4 II kinetic energy, the Schwerer Gustav shell kinetic energy (I don'…

Your calculation is flawed, probably intentionally.

A-380 is not a shell, it's a soft sausage 70 meters long.

The fuselage collision would be stretched in time, greatly diminishing impact forces. It's large cross-section means it couldn't even focus on a single cask. The 40 F-4s analogy is incorrect again, as the tail of the plane wouldn't be hitting the target, it would be hitting the soft pile of crap from the nose and midsection.

The engine is the only dangerous part as far as collisions against concrete go, and even then not so dangerous.

Again, let's say we got unlucky and the 4 engines of an A-380 breached 4 casks. Would it be bad? Of course. Would it be as bad as 9/11? No way.

The fireball would lift some dust in the air and quickly dilute it. Nuclear fuel is essentially ceramic and doesn't melt until 2800C, way above what jet fuel can do (steel beam anyone?). Some fission products would be included in the cloud.

Local decontamination effort would be many orders of magnitude below that of Chernobyl (where health effects on cleanup workers proved impossible to measure) and probably on par with 9/11 cleanup.

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

#440

Post by GekkePrutser »

Nimitz14 wrote: post #308
rgbrenner wrote: post #149

BBC on nuclear: asking the questions that don't matter. You know what the real problem with nuclear is? It's not economically competitive. What if I told you: you can invest in a project that will tie up your money for 10+ years and once it's completed will provide energy for 10x the current cost of solar/wind. And while youre building this plant, solar/wind and batteries will keep getting cheaper.. and by the time y…

The building costs are high because noone builds them. It's always expensive when each project is a "first" for the people involved. > once it's completed will provide energy for 10x the current cost of solar/wind. Ah right that must be why electricity costs in Germany are so high and so low in France LOL

France strongly subsidised their plants due to the side effects to their nuclear weapons program.
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