Environmentalists and Nuclear Energy

[coppice]

In current practice, "cleaning up the leftovers" means entombing them in ways that make future PUREX reprocessing infeasible. This is wasteful and ignorant.

You are making some big assumptions about what might be feasible,  should the need arise to use this stuff later on. At least the stuff is packed safely (we hope) and not dispersed.  One of the most wasteful things we do in waste disposal is spreading the material so thinly that it is implausible that we could ever gather the stuff up for future reuse. Good luck ever trying to get workable quantities of rare elements back from all the world's land fills.

[CCitizenTO]

Nuclear power using LWRs is incredibly wasteful of a scarce resource (²³⁵U) and can only meet our energy needs for 100 years at best.

Doesn't Uranium after it's been used turn into some other radioactive element or there's some means to turn it into a fuel source again. I think someone mentioned that we have enough radioactive material on the planet to cover our energy needs for the next 200,000 years if you take into account lower level nuclear fuel sources like Thorium and the like.

The problem with nuclear power is not that people are using it to generate electricity. The problem is people complaining about the byproducts and the problem of byproducts would not be there if we a a global community agreed to say ship all our hazardous nuclear waste somewhere to be reconstituted into usable fuel again.

[helius]

Doesn't Uranium after it's been used turn into some other radioactive element or there's some means to turn it into a fuel source again. I think someone mentioned that we have enough radioactive material on the planet to cover our energy needs for the next 200,000 years if you take into account lower level nuclear fuel sources like Thorium and the like.

No, not really. After ²³⁵U fissions, you have waste isotopes like strontium and cesium that are radioactive but not fissile. What you can do is to design the reactor so that the neutrons from the fission can be captured by other elements. This causes transmutation into a target isotope, hopefully one with economic value. We do this all the time to make medical isotopes. But making fissile materials this way (a breeder reactor, like Fermi built at Oak Ridge) is controversial because there is a fear that it makes nuclear weapons easier to make and harder to control.
In a traditional breeder reactor, ²³⁸U is transmuted to ²³⁹Pu, which is fissile and can be used for fuel. The transmutation of thorium to ²³³U is also promising since thorium is a relatively common element, but it hasn't yet been shown to be a viable process.

The problem with nuclear power is not that people are using it to generate electricity. The problem is people complaining about the byproducts and the problem of byproducts would not be there if we a a global community agreed to say ship all our hazardous nuclear waste somewhere to be reconstituted into usable fuel again.

Only the fissile byproducts are usable as fuel. It's possible for a reactor to produce more fuel than it consumes, but a lot of other materials get irradiated and simply become (high or low level) nuclear waste. Those do need to be disposed somehow, but for the most part reprocessing isn't even part of the plan now, which is unfortunate.

[Kleinstein]

Reprocessing the used fuel from current reactors is a two sided thing: One could recover the left over fissile ²³⁵U and newly produced ²³⁹Pu. This way one might recover something like 25%-50% of the original fissile fuel. Also there is little reduction in radioactivity of the rest (as PU is a significant part of the medium term radioactivity). However reprocessing also produces quite a lot of low level waste from chemicals used. So the overall wast volume to store away goes up quite a bit and the radioactivity is not reduced very much. Reprocessing also adds significant costs - the recovered fuel is currently much more expensive than new one, though costs are open to debate. Also currently reprocessing only works that way for one cycle - so reprocessing fuel from the second cycle will be more difficult and would result in lower quality fuel.

Thorium as a fuel needs reprocessing to make is a real fuel and not just a small addition. However reprocessing thorium based fuels is even more difficult and expensive.

How much fuel is available also depends on how much you are willing to pay for uranium. There is a lot of uranium available in see water, but the costs are to high for just using the U235 in this. If the rest could be used in a beading cycle too, the higher price could be acceptable - this way going towards 200000 years as a more theoretical limit. A similar number applies to thorium if used with hypothetical perfect recycling. Currently (and in foreseeable future) this is way to expensive (e.g. more expensive than uranium from see water), as the recycled thorium is also radioactive and thus more of a waste than of any practical use.

[Someone]

Nuclear power using LWRs is incredibly wasteful of a scarce resource (²³⁵U) and can only meet our energy needs for 100 years at best.

Doesn't Uranium after it's been used turn into some other radioactive element or there's some means to turn it into a fuel source again. I think someone mentioned that we have enough radioactive material on the planet to cover our energy needs for the next 200,000 years if you take into account lower level nuclear fuel sources like Thorium and the like.

The problem with nuclear power is not that people are using it to generate electricity. The problem is people complaining about the byproducts and the problem of byproducts would not be there if we a a global community agreed to say ship all our hazardous nuclear waste somewhere to be reconstituted into usable fuel again.

Its quite complicated, even the most optimistic fuel cycle plans still involve huge amounts of very hard to handle material going around and in the waste streams. I'm not away of any solutions that eliminate the problems of handling highly active materials or eliminate them in the waste stream.

Unlike fuels you might be familiar with (ones that burn) nuclear fuel poisons its self to the point where it wont sustain a chain reaction, then you have to either reprocess it or buy some new fuel. Reprocessing has proliferation (political) problems and is expensive, so its often more economical to work around a simpler fuel cycle where you simply dont reprocess the fuel and use it very inefficiently.

Thorium as a fuel needs reprocessing to make is a real fuel and not just a small addition. However reprocessing thorium based fuels is even more difficult and expensive.

How much fuel is available also depends on how much you are willing to pay for uranium. There is a lot of uranium available in see water, but the costs are to high for just using the U235 in this. If the rest could be used in a beading cycle too, the higher price could be acceptable - this way going towards 200000 years as a more theoretical limit. A similar number applies to thorium if used with hypothetical perfect recycling. Currently (and in foreseeable future) this is way to expensive (e.g. more expensive than uranium from see water), as the recycled thorium is also radioactive and thus more of a waste than of any practical use.

A lot of it comes down to economics. There are some really promising looking fuel cycles with thorium or breeder reactors but even though they could produce less activity per unit of energy delivered, their lifecycle cost of energy is high enough that they wont attract any real investment.

[moz]

I'm mildly surprised no-one has mentioned John Quiggin yet. He's an Australian economist who is quite scathing about both the timelines and economics of nuclear power, at least in Australia. A quick search of his site brings up a series of posts, and this one seems like a good summary/starter.  He mentions the US situation here

even if Australia could match the construction rates observed in the US, the time necessary to set up a regulatory infrastructure and undertake greenfield site selection would delay the commencement of generation until at least 2040. Since the publication of this article, further construction delays have been announced for both US and Chinese AP1000 projects. On the basis of more recent US experience, even a 2040 startup date for Australia appears highly optimistic.

So it depends a lot on what you want nuclear power for, and what your expectations are. If you just want to be able to say "hey, we have a nuclear power station", that's definitely possible and a whole bunch of countries have done that. But if you want to make a serious dent in greenhouse gas emissions the lead times for nuclear start to get ugly. To make it work you really need an authoritarian government willing to put safety well down the list of considerations. That lets "you" build a plant in 10-20 years from idea to grid connection. I'm personally not a fan of the Russian or Chinese solutions to those problems.

[JulietMikeBravo]

Glad to see a polite discussion on nuclear energy.

Personally I see nuclear as follows:

Run properly, it is a highly dependable and safe way of generating electricity and heat. I don't think renewables are bad, but as long as energy storage is in development we need backup power, and I'd rather have waste concentrated in small spots than put in the atmosphere and polluting the whole planet. Nuclear waste sounds scary but has never affected people on the same scale as global warming has.

I do have certain concerns about nuclear energy. When poorly managed it can have bad results. For example, the combination of a large deployment of nuclear energy and a seismically unstable region isn't desirable. Currently used LWR reactor tech is wasteful as only a fraction of the fuel is fissioned before too much fission products and nuclear poisons build up. Modernization of reactor tech is delayed because use of nuclear tech is too highly regulated, in part due to distrust of nuclear tech and the industry.

Still, I think it is stupid to discard nuclear altogether, there are craptons of energy in natural uranium and thorium. We will probably need it.

[moz]

I don't think renewables are bad, but as long as energy storage is in development we need backup power

For much of the world pumped hydro is an old technology (1890's) that's fairly readily available. Even Australia can use it, thanks to putting 80% of our population on the east coast. I don't imagine we'll stop developing storage until it becomes irrelevant (perhaps due to fusion power generators that fit in cellphones?) The fact that we're constantly seeing new storage technologies says to me that there are still improvements being made.

Sadly when we look at nuclear fission the opposite seems to be happening - existing designs are being retired at the same time as new ideas are falling short. Partly that's because of the cost of experimentation - when someone needs tens of billions of dollars and a couple of decades to perform an experiment the number of experimenters is necessarily very small. But with renewable generation and electrical storage the scale is smaller and the timelines shorter. Even at the "novel chemistry" end, a few tens of millions for less than a decade is usually enough (Redflow in Australia, for example). You can DIY as well, there are a lot of "homemade powerwall" people around. Bob help us all if people start to DIY thermal fission generators.

use of nuclear tech is too highly regulated

I suggest that fission power is heavily regulated because we can see the consequences of not doing that. The list of sites that have to be actively managed for centuries due to regulatory failures in the nuclear industry is longer than the one example that I think we could accept as a learning experience. Seriously, looking at Three Mile Island makes me say "more rules are needed", not "clearly that would have been better with less oversight and government interference". You don't even have to use Chernobyl or Mayak, and for that matter Fukushima also works as an example of why we need more regulation not less. We just don't have examples of renewable disasters or sites that renewables have made into thousand year nightmares.

[CatalinaWOW]

I suggest that fission power is heavily regulated because we can see the consequences of not doing that. The list of sites that have to be actively managed for centuries due to regulatory failures in the nuclear industry is longer than the one example that I think we could accept as a learning experience. Seriously, looking at Three Mile Island makes me say "more rules are needed", not "clearly that would have been better with less oversight and government interference". You don't even have to use Chernobyl or Mayak, and for that matter Fukushima also works as an example of why we need more regulation not less. We just don't have examples of renewable disasters or sites that renewables have made into thousand year nightmares.

I don't know what your list of renewables includes, but if it includes wood, biomass and human waste there are many places about the planet that have been made into nightmares for periods that approach or exceed your 1000 year mark.  The whole Eastern Mediterranean (the land of milk and honey described in the Christian Bible) was turned into desert wasteland by improper use, and much remains that way, though in the twentieth century reclamation efforts made significant progress.  Hydroelectric and water storage dams have caused the extinction of some aquatic species and have caused large scale declines of others that may or may not be recoverable on a 1000 year scale.  That is not to say that controls to prevent this aren't easier in some ways than nuclear, or that the nightmares are equally bad (though different folks bad dreams are different).  But all technologies used on large scales have risks and downsides.  Renewables are not an exception to this.  Solar and wind power have not yet been implemented on large enough scale to be sure that there are not significant side effects to these technologies.

[moz]

I don't know what your list of renewables includes, but if it includes wood, biomass and human waste there are many places about the planet that have been made into nightmares for periods that approach or exceed your 1000 year mark.  The whole Eastern Mediterranean was turned into desert wasteland

I'm not convinced that going back several millennia and then saying that a particular large geographic area was primarily devastated by renewable energy generation is meaningful. Was firewood gathering the really major cause of the disaster? The "Eastern Mediterranean" appears not to be used by geographers, so I'm not entirely sure which specific site you mean.

My broader point is that those cases are rare and arguable unless you broaden them to include all human activity in the area.

I'm reluctant to get into local extinctions, for much the same reasons as arguing about bird strike for wind or solar is hard. To talk meaningfully about it you need pretty intense research and the argument ends up being as much definitional as statistical. Are the birds that used to live around an open cut mine locally extinct because, well, it's an open cut mine? Do they count as killed by the mine in the same way as birds killed by wind turbines count?

And then there's this amazing bit of writing about the Mediterranean desert that popped up in my search results (caution: faith-based material). It's worth reading just for the mind-boggling nature, if you're into a bit of casual boggling.

[CatalinaWOW]

I don't know what your list of renewables includes, but if it includes wood, biomass and human waste there are many places about the planet that have been made into nightmares for periods that approach or exceed your 1000 year mark.  The whole Eastern Mediterranean was turned into desert wasteland

I'm not convinced that going back several millennia and then saying that a particular large geographic area was primarily devastated by renewable energy generation is meaningful. Was firewood gathering the really major cause of the disaster? The "Eastern Mediterranean" appears not to be used by geographers, so I'm not entirely sure which specific site you mean.

My broader point is that those cases are rare and arguable unless you broaden them to include all human activity in the area.

I'm reluctant to get into local extinctions, for much the same reasons as arguing about bird strike for wind or solar is hard. To talk meaningfully about it you need pretty intense research and the argument ends up being as much definitional as statistical. Are the birds that used to live around an open cut mine locally extinct because, well, it's an open cut mine? Do they count as killed by the mine in the same way as birds killed by wind turbines count?

And then there's this amazing bit of writing about the Mediterranean desert that popped up in my search results (caution: faith-based material). It's worth reading just for the mind-boggling nature, if you're into a bit of casual boggling.

I agree that it is hard to separate all of the variables, and particularly hard since most of those who try are proponents of one or another energy resource and end up with biases - intentional or otherwise. 

I could give you a narrower geographical area - the countries of Lebanon and Israel.  Then we could get into a discussion of whether burning wood for room heating and cooking is energy generation since it doesn't involve electricity, and what percentage of the environmental damage was "energy" related vs other human activity.  For species extinction I was specifically thinking of the Colorado River system in North America.  Here the Bonytail (a half meter size fish) is functionally extinct with no known wild breeding populations and a declining captive population, and others like the Pikeminnow (a two meter fish) and the Humpback Chub (a one third meter size fish) which are now endangered.  As far as I know all biologists believe that dams on the Colorado river system are the primary and perhaps sole cause of their problems, with changes in water flow and temperature being the specific problems.

Interpretation of the devastation caused by these events is again subject to interpretation.  While no one can argue about the half lives of radioactive products, and while there is not too much argument about the existence of excess deaths due to exposure to radiation the responses diverge radically from there.  For example, I grew up in Colorado, spending most of my time at altitudes that varied from 2000 to 2700 meters, with occasional forays over 4000 meters.  Due to natural radioactivity in the soil and higher cosmic ray radiation from the thinner atmospheric belt people living in that area can expect a significantly higher rate of radiation induced cancers than those living in Mississippi or Denmark.   Not to mention cataracts and a host of other altitude related ailments.   No one suggests evacuating or cordoning off my birthplace.  But people casually talk about the need to cordon off areas for 10000 years or more on the chance that radiation levels in pockets might exceed a safety standard.  Chernobyl is viewed by some as a radioactive wasteland, and by others as the place they live.  Those who have chosen to live there are at higher risk, but their daily lives are far more affected by the lack of economic community that exists because of the quarantine than it is by the radiation.

[mtdoc]

When evaluating the health hazards of radiation it's very important to understand that there are very large differences in the risks posed by different sources of radiation and different isotopes. 

The risks from the cosmic radiation that increases with altitude or from naturally occuring earth sources like radon are minuscule relative to the risks posed by some of the fission products of nuclear reactors such as isotopes of iodine, caesium and strontium.  And the relative health hazard of different isotopes depends not only on their relative radioactivity but also on their biological activity and propensity to bioaccumulate.

[CatalinaWOW]

When evaluating the health hazards of radiation it's very important to understand that there are very large differences in the risks posed by different sources of radiation and different isotopes. 

The risks from the cosmic radiation that increases with altitude or from naturally occuring earth sources like radon are minuscule relative to the risks posed by some of the fission products of nuclear reactors such as isotopes of iodine, caesium and strontium.  And the relative health hazard of different isotopes depends not only on their relative radioactivity but also on their biological activity and propensity to bioaccumulate.

Absolutely true.  But I suspect that because of durability of exposure (cosmic radiation will not change in human history) and widespread exposure (The high Rockies, the Andes, the Alps, the Tibetan plateau), the total number of excess deaths due to living at altitude will be comparable to those from the three major nuclear incidents.  Particularly if measured over the timescales some are using for nuclear safety.  Three or four generations from now the effects of these incidents will have faded largely into the background, while cosmic rays will keep ticking along.

My point isn't that nuclear power is safe.  If we continue to employ it as we have in the past you can assume that the contamination from accidents will be continually refreshed.  The point is that this is just another example of the perceived risk being far different from other kinds of risk.  We could run lots of nuclear power as ineptly as the Russians did at Chernobyl and death from nuclear radiation would still be pretty far down the cause of death list.   Certainly below the cost of burning and using coal if you total up mining accidents and the various types of atmospheric releases.

Look at the possibilities -  If you banned living at high altitude you could create huge nature reserves.  Save numerous endangered species.  Save large amounts of heating energy.  Eliminate or reduce deaths from snowslides and landslides.  Safe human lives from excess cancers (remembering that UV radiation is worse up there also).  A safer better world.  And just a day late for 4/1.   

[tautech]

But I suspect that because of durability of exposure (cosmic radiation will not change in human history) and widespread exposure (The high Rockies, the Andes, the Alps, the Tibetan plateau), the total number of excess deaths due to living at altitude will be comparable to those from the three major nuclear incidents. 

You don't consider the numerous atmospheric tests in the US, Australian outback and on Pacific atolls major ? 
Most of these areas are still roped off as nogo regions. 

Sure we know a lot more today but damage has been done that will take generations to become safe if ever.

So that you know where I stand, I support the safe use of nuclear energy for our future energy needs.