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Ultra Safe Nuclear

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Re: Ultra Safe Nuclear

#151

Post by epistasis »

cmehdy wrote: post #130
jka wrote: post #24

Earlier quoted context omitted.

I don't know, and I have been wondering whether much of the evident pro-nuclear lobbying recently (it seems apparent on many threads here related to energy generation) might be due to the nuclear industry being in serious threat of becoming obsolete. I've harped on about this many times before, but the levelized cost of energy[1] for renewables like solar and wind power is substantially cheaper than nuclear power now…

I'll alleviate your concerns: it is not due to a big nuclear conspiracy aiming at making Big Nuclear fill its pockets, but by people who look at what physics dictates and notice that with our energy consumption things just don't add up. So you will see an increasing amount of (1) posts about nuclear, and (2) posts about de-growth or accepting to shrink economies through less consumption and production, not because th…

There is absolutely no "physics" that goes into those postings. It's just some gut feelings. I've come across this at least a dozen times, with people just sure that "physics" says something, but there is no physical principle that requires we decrease energy use to power the entire world with renewables and storage and possibly hydrogen or other synthetic carbon fuels.

We can power all of the developing world at Western energy levels with renewable energy. Our GDP is increasing even as the amount of primary energy per person decreases. It's no longer the 1970s and a lot of assumptions from then have been proven to be very very wrong.

Re: Ultra Safe Nuclear

#152

Post by hcurtiss »

noja wrote: post #141
manfredo wrote: post #47

Earlier quoted context omitted.

1. Forever. Uranium is a heavy metal, it's toxic regardless of it's radioactivity. 2. The US already has one [1]. Congress stopped it's opening, but it's sitting there built ready to be used. Europe also is constructing a disposal site [2] 3. Like I wrote in my comment, bury it in an area with no groundwater. 4. France does recycle it's nuclear waste. 5. We do, as I pointed out above. And for the second time, this wa…

> Forever How can anything with a cost that lasts forever be cheaper?

Because most reasonable people discount future costs, and those sufficiently distant to zero.

Re: Ultra Safe Nuclear

#153

Post by loeg »

xibalba wrote: post #3

Assuming nuclear truly can be ultra safe, how do you convince a public that has seen Chernobyl, Three Mile Island, and Fukushima to get on board? Particularly when the "competition" (solar, wind, etc) has such a strong tailwind.

Both the major incidents (Chernobyl and Fukushima) were reactors designed in the era of slide-rules. Neither is a 3rd or 4th generation design. Chernobyl was a bad design, and the incident resulted from Soviet mismanagement (keeping known RBMK reactor flaws secret) in tandem with local mismanagement (the test protocol was completely fucked).

Fukushima required active cooling and could not cool itself using its own power output. And the backup generators were below sea level and the thing was on a fault line.

Neither caused major loss of life.

Three Mile Island was a scare, and did not cause significant damage or loss of life.

Any newly constructed reactor would not have the design flaws of the Soviet RBMK and would be designed to fail-safe.

Re: Ultra Safe Nuclear

#154

Post by cmehdy »

epistasis wrote: post #151
cmehdy wrote: post #130

Earlier quoted context omitted.

I'll alleviate your concerns: it is not due to a big nuclear conspiracy aiming at making Big Nuclear fill its pockets, but by people who look at what physics dictates and notice that with our energy consumption things just don't add up. So you will see an increasing amount of (1) posts about nuclear, and (2) posts about de-growth or accepting to shrink economies through less consumption and production, not because th…

There is absolutely no "physics" that goes into those postings. It's just some gut feelings. I've come across this at least a dozen times, with people just sure that "physics" says something, but there is no physical principle that requires we decrease energy use to power the entire world with renewables and storage and possibly hydrogen or other synthetic carbon fuels. We can power all of the developing world at Wes…

I can't help you if you don't even understand the scale of renewability of resources such as oil and gas, the ratio of energy extracted to energy put into the various kinds of machines that produce what we need to keep our energy consumption up, the limits to energy extraction for solar power, the lack of predictability and controllability of energy sources other than gas-oil-coal-nuclear, and the CO2-related effects on the atmosphere for the first three out of those four, the depletion of current controllable energy sources, and the energy available in the various kinds of uranium-plutonium-thorium isotopes which lead to the different kinds of nuclear power plants. Amongst other things which take hours of actually trying to wrap your head around the problem instead of putting your fingers in your ears and screaming bloody murder.

Because apparently you seem to believe that "there is absolutely no 'physics'" in all of this.

edit: as a side-note, take a look at all the countries that have increased their renewables energy consumption and show me that it corresponds to a decrease in production and investments of {oil or gas or coal or nuclear}, i.e. controllable energy sources. You will soon see that the sources that cannot be predicted in a way that ensures your fridge continuously works and you can take a hot shower at all hours of the day are only secondary sources that people are happy to have (and renewables are a great thing to invest in) but that in itself is not enough - unless, again, one accepts that their patterns of behaviour and consumption would change drastically, which is only one of the many possible discussions around the evolution of our societies that you seem to be so anxious to sweep under the rug.

Re: Ultra Safe Nuclear

#155

Post by lmilcin »

manfredo wrote: post #17
grawprog wrote: post #8

So why has nuclear waste become a thing that's not mentioned anymore? It was a pretty big thing in the 90's, now it seems to get brushed under the rug for all this 'safe' nuclear power marketing. It's mot just meltdowns and containment breaches that are a problem with nuclear power. None of the renewable alternatives produce radioactive waste that needs to be stored and dealt with. https://en.m.wikipedia.org/wiki/Rad…

Because it's not a problem. There's actually very little of it. It occupies a volume the footprint of a football field and 10 yards high [1]. Storing it is pretty foolproof: bury it in an area with no aquifer. The main risk of contamination is getting into the groundwater. If there's no groundwater the risk of contamination is eliminated even if the containers decay over time. And lastly, it doesn't make sense to bur…

Yeah, exactly. Even though it is costly to deal with, per kilogram, there is very little of it when compared to amount of energy produced. An atomic plant might use couple dozen tonnes of fuel which is peanuts compared to the amount of waste from coal power plant.

There are no technical problems with storage that we can't solve. The biggest problem is that nobody wants it around.

Re: Ultra Safe Nuclear

#156

Post by hairytrog »

Two interesting things to see here, of many. They are really planning the sites to be temporary compared to the solar/wind/ and other industrial power plants that have little or no plan for returning their sites to the original virgin soil. And two, they seem to use a molten salt loop like in concentrated solar to meet variable demand without changing the power level of the reactor, which you can't really do because of Xenon poisoning. So it's like a natural gas plant in its ability to deliver power, but clean and holds 20 years of fuel inside the reactor.

Re: Ultra Safe Nuclear

#157

Post by Symmetry »

manfredo wrote: post #75
beders wrote: post #51

Earlier quoted context omitted.

> First, point out that Chernobyl, 3 Mile Island, and Fukushima amount to extremely small numbers of deaths relative to the power these plants generated. I keep seeing justifications like that and it makes me want to puke. First of all: The total number of victims is unknown and it is still rising. Even for Chernobyl. Second: It costs tens of billions of dollars to clean up these messes. Paid for by the cow you can m…

> I keep seeing justifications like that and it makes me want to puke. First of all: The total number of victims is unknown and it is still rising. Even for Chernobyl. The total number of victims was unknown for Chernobyl. We didn't know what the impact on cancer rates would be. But it isn't the 1980s anymore. We can compare the rates of cancer and other radiation related illnesses among the people who experienced Ch…

A number of people did die because of the Fukushima evacuation, though, through things like interruption of medical care. And if there hand't been an evacuation there would have been a few radiation deaths. The total is still only 10x the number of air pollution deaths you'd expect from a coal plant providing the same number of megawatt-years and very few nuclear plants melt down but lets be accurate.

Re: Ultra Safe Nuclear

#158

Post by hairytrog »

Seems like their claim to "Ultra Safe" is actually merited based on a first principles look at the power density. They claim 1.24 W/cm^3 versus 20-40 W/cm^3 in normal reactors. The high power densities mean you have to be able to cool the reactor, even when you shut down the reactor because reactors take a long time to actually turn off. With such low power density, it should be no problem to cool down the reactor. It'll just cool down naturally, like a hot pot. In fact the metric to look at would be power per core surface area.

Re: Ultra Safe Nuclear

#159

Post by epistasis »

cmehdy wrote: post #154
epistasis wrote: post #151

Earlier quoted context omitted.

There is absolutely no "physics" that goes into those postings. It's just some gut feelings. I've come across this at least a dozen times, with people just sure that "physics" says something, but there is no physical principle that requires we decrease energy use to power the entire world with renewables and storage and possibly hydrogen or other synthetic carbon fuels. We can power all of the developing world at Wes…

I can't help you if you don't even understand the scale of renewability of resources such as oil and gas, the ratio of energy extracted to energy put into the various kinds of machines that produce what we need to keep our energy consumption up, the limits to energy extraction for solar power, the lack of predictability and controllability of energy sources other than gas-oil-coal-nuclear, and the CO2-related effects…

You can't "help" me understand your claim because it is baldly false!

There's an entire field that models different grids and transitioning to carbon free energy. Using fine-grained weather patterns, they optimize for various factors such as cost, by timing out deployments of renewable resources, nuclear, transmission, storage, etc. using projected costs over the next few decades.

There are huge fights in the field, particularly over nuclear, but nobody, literally nobody has said it's impossible. The debate is how much cheaper nuclear energy will make the energy transition.

So if there's some sort of "physics" that precludes the possibility of what people have already made detailed plans for, you should probably publish that result. But it seems unlikely that you have found something they haven't.

Response to your edit: you are shifting the point, without bothering to back up your initial claim. Nonetheless, you are shifting to a new false claim, that "renewables don't decrease carbon output. This is also clearly false:

https://www.eea.europa.eu/data-and-maps/indicators/overview-...

The term that is used in the industry isn't "controllable," but rather "dispatchable" energy source. Europe is showing that we can get awfully close to 50% renewable, non-dispatchable energy, without really any storage and reduce carbon output. Storage, demand response, and increased transmission will likely close the rest of the gap.

Re: Ultra Safe Nuclear

#160

Post by lrem »

merb wrote: post #31
manfredo wrote: post #17

Earlier quoted context omitted.

Because it's not a problem. There's actually very little of it. It occupies a volume the footprint of a football field and 10 yards high [1]. Storing it is pretty foolproof: bury it in an area with no aquifer. The main risk of contamination is getting into the groundwater. If there's no groundwater the risk of contamination is eliminated even if the containers decay over time. And lastly, it doesn't make sense to bur…

1. How long does it need to be kept safe? 2. How to find a storage facility that can keep it safe that long? 3. How to ensure that a facility does not contamine other stuff in X years? 4. if it is recycable why does nobody do it? 5. if it is so easy to store it safe, why does not country have a TRUE final depot? yeah coal is bad, but why compare it to coal in the first place when we want to reduce such things anyway?…

Because the alternative to the nuclear plants that have shut down has reliably been ramping up fossil fuels. Note that nuclear has the longest of power up/down cycles, so it's mostly practical for providing the base load. I.e. you cannot practically replace nuclear with solar, as its home turf is night time.
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