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The Nuclear Approach To Climate Change
Harperdog writes "A new roundtable at the Bulletin of the Atomic Scientists explores the question of whether nuclear energy is the answer to climate change, particularly in developing countries where energy needs are so great. This roundtable, like the ones before it, will be translated into Chinese, Arabic, and Spanish within a week of each article's publication. Here's a summary: From desertification in China to glacier melt in Nepal to water scarcity in South Africa, climate change is beginning to make itself felt in the developing world. As developing countries search for ways to contain carbon emissions while also maximizing economic potential, a natural focus of attention is nuclear power. But nuclear energy presents its own dangers."
The problem with burning fossil fuels isn't the net increase in entropy. It's the gasses that trap heat in the atmosphere.
While renewable energy technology is the answer, nuclear energy is an excellent interim solution.
Anyone whose concerned about safety, I want you to go and look up how many nuclear reactors are over 30, 40 years old. These antique behemoths are being run because there are many unnecessary obstacles to overcome if you want to build a new plant. Nuclear technology as well as construction and information systems have improved dramatically each decade, so how is it that people can react to modern reactors as if they have no safety advantages over their retro-ancestors?
Short answer: it does matter.
Longer answer: The amount of energy that we use is a small fraction of the amount of energy that the earth receives from our nearest star (aka the sun). The heat we create from the energy that we use is also a small fraction of the heat the earth retains from the sun and the earth retains in its molten core. So if we are doing something to change the amount of heat we retain from the energy we receive from the sun** with different sources of power, it could certainly make a difference.
Of course the $64G question: does buring carbon based fuels significantly change the amount of heat we retain on earth? Probably (that is the whole AGW debate). Of course we don't know for sure, but there is some evidence that it is true, but the bigger picture may be that things totally out of our control (e.g., volcanos, meteors, solar variation, etc), may in the end drown out our effect, but that doesn't mean the effect isn't there.
**for completeness, we might also consider the distribution of the heat between the surface and the molten core, but to be fair, other than the trivial amount of geothermal energy we use, there's a negligible amount to think about here.
A small scale nuclear war to produce a nuclear winter to offset global warming will do the trick, and possibly cut the population at the same time.
"To those who are overly cautious, everything is impossible. "
If you took all the effort and energy spent, developing green energies, clean coal, fracking. Couple that with all the energy spent fighting each of them for what ever reason. Just think how safe and efficient 2020 nuclear power plants could be. A new nuclear plant hasn't been built in the US since what the 80's. Thats 30 YEARS. Just think of the improvements and innovations we could make or had made had we pursued it. If you really think that global warming is the end of days, then how can you not embrace nuclear? Its like vegetarians who believe in evolution. It just doesn't make since.
Just not the king we use. Uranium and plutonium are terrible ways to achieve nuclear power. There is relatively little power output and a large amount of waste product, which we know will kill us if we even come close to it. The only benefit is being able to create nuclear weapons.
Thorium on the other hand produces much more power per gram and has very little waste. The waste it does produce is exceedingly less dangerous than the current 1950s style reactors.
Plus, there is craps loads of the stuff everywhere. Time to switch. I think we have more than enough Nukes to destroy the world population many times over, so there is no need to stick to a dangerous tech just so we can make more.
And even nuclear power is a problem there - mining and enrichment are very expensive phases and they produce carbon dioxide.
It's a question of calculating the total emissions for each type of energy source, and it's not an easy process.
Add to that the environmental impact that each type of energy has, both under normal conditions and under extreme conditions. Just look at Chernobyl - that disaster made quite an impact over a large area for a long time. Fukushima wasn't as bad, and partially thanks to a large amount of the spill being diluted into the pacific.
Hydroelectric power isn't free from making an environmental impact, but it's also of a more local type and if a disaster strikes the area suffering will be usable relatively soon. Wind power has it's own problems, one is that it's not very efficient so it requires a lot of space, and the wind doesn't always blow.
Coal and oil - they are finite known resources. We better prepare ourselves for the day when they run out by looking for alternative energy solutions.
Geothermal energy is quite interesting. It's available in many locations, but requires some investment to be usable.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
The amount of heat generated by power consumption is small compared to the energy received from the sun and emitted back into space. The earth receives around 175 PW of power from the sun, and the amount emitted back into space is around the same providing an equilibrium. The global power consumption by everyone on the planet is around 15 TW. So that's a ratio of 175 PW to .015 PW, which means we consume around .008% of the amount of power we receive from the sun / radiate into space.
A lot of our energy comes from fossil fuels, so basically that is releasing energy that was solar originally, so technically we aren't adding energy to the earth. Solar, geothermal and hydro is just converting / moving energy around from place to place within the existing system, so that doesn't add energy either. Nuclear would be the only way we'd be changing the amount of energy in the system, as we're directly converting it from mass. So it would matter what power source we use from that standpoint, and if your argument has merit, then nuclear would be the issue from an entropy standpoint.
Better known as 318230.
Thorium on the other hand produces much more power per gram and has very little waste. The waste it does produce is exceedingly less dangerous than the current 1950s style reactors.
You forgot most important part (assuming you are referring to the molten-salt thorium reactors), there is no boom. The reactor can never go out of control. Hence there is never a nuclear cloud or fall out. And also, the reactor can be designed to be started and stopped in minutes rather than hours or days or months.
And even nuclear power is a problem there - mining and enrichment are very expensive phases and they produce carbon dioxide.
It's a question of calculating the total emissions for each type of energy source, and it's not an easy process.
If you had practically unlimited and cheap electrical power available from nukes (an awfully big "if"), you could eliminate much of the carbon emissions while extracting nuclear fuel. If nothing else you could split hydrogen out of water and use hydrogen as a fuel for equipment and processing plants. There'd still be some carbon emissions from things like deforestation during mining, etc.
1. total world energy production - 2012 = 12 x 10^6 kT oil - thus about 5 x 10^20 J.
averaging over 356 days => average power produced=1.6 x 10^13 W
2. Solar constant - 1361 W/sq m
Surface of Earth intercepting Sun's energy = PI*(6384 km) ^ 2 = 1.28 10^14 sq m
Sun's radiation total power on Earth = 1.74 x 10^17 W
Average power produced by the world / Sun's radiation power = 0.01%. Yet, until recently, Earth (or Gaya - to encompass the ecosystem as well) managed to deal with the Sun's radiation without warming.
Conclusion: the major cause of the warming is very unlikely caused directly by the world's energy production (ultimately transformed in heat) - as it contributes with only 0.01%. Look elsewhere.
Questions raise, answers kill. Raise questions to stay alive.
but the bigger picture may be that things totally out of our control (e.g., volcanos, meteors, solar variation, etc), may in the end drown out our effect,
Total from conduction, vulcanism, and plate tectonics: 0.1 W/m^2
Total from solar variation since 1750: 0.12 W/m^2
Total from human activities so far: 1.6 W/m^2
Nothing is going to drown out our effect (Ref IPCC AR4).
For completeness, the worldwide electricity production is about 2 TW. The heat from combustible fuels not used for electricity is probably comparable. Compare this to the value for conduction, vulcanism, and plate tectonics which has a value of about 44 TW (~0.1 W/m^2).
**for completeness, we might also consider the distribution of the heat between the surface and the molten core, but to be fair, other than the trivial amount of geothermal energy we use, there's a negligible amount to think about here.
Well thanks at least for including it for completeness, since that one source exceeds our current electrical energy needs for the next thousand years with current technology - by which time technology may have advanced a wee bit. The Yellowstone Caldera by itself throws off more thermal energy each minute than, converted to electrical energy, the world requires. And cooling that damned thing might be in our best interest since it's likely to bury 60% of the US in ash someday - again, as it has many times before.
Solar is great too, and can also be baseload power with a big enough heatsink - or balanced with geothermal plants that produce on demand solar and wind can use geothermal for a heatsink / corrector for low/no production. Geothermal plants can with slant drilling occupy a tiny surface space and tap a vast region, and can be baseload power as well as a peak power source.
There are a lot of other sources we aren't using right now. Petroleum refineries throw off a lot of waste heat, as do pulp mills, organic composting, server farms, volcanos, iron and aluminum and glass refineries. Any place there is a reliable significant thermal delta is an opportunity to reap electrical power, and the question is whether or not it can be done economically. As science progresses the delta and size of the installation becomes smaller. It's not as much "geothermal" as it is "thermal delta" electrical power.
There is no reason not to use both solar and geothermal to diminish our dependence on oil.
Nuclear works on thermal deltas too, but doesn't exploit them enough. Spent fuels, for example, heat their pools for a decade before they're considered "cool" enough to put into permanent storage (should any ever come available). That's a waste heat that's dissipated by evaporation (phase change) of water rather than claiming it as electrical power through modern energy capture technologies. Given modern technologies the spent fuel might give more electrical power than the reactor if it were exploited. I have issues with the whole "we don't have to take the trash out" mentality of nuclear proponents, but I have no problem with making the most of what they do.
We need to come to grips with the idea that "a big enough thermal delta is an electrical energy source." And then moderate the "Big enough" term with advances in technology. That's the ultimate recycling: finding utility for the thermal energy we are now throwing away.
Help stamp out iliturcy.
things totally out of our control (e.g., volcanos, meteors, solar variation, etc), may in the end drown out our effect
the earth had reached sort of an equilibrium - CO2 released by volcanoes etcetera was being cancelled out by plants taking it out of the atmosphere, but in the latest few centuries humans have changed the co2 concentration in the atmosphere from 200/250 to 400 ppm
Yes, I'm left. You have a problem with that?
Global Warming, Nuclear Energy, Agrarian Society
This is news to few; heck the bumper sticker I made for myself with that saying has this in its footer metadata: "Made on 4/24/2007 1:19 PM".
I hear Richard Branson has repeatedly tried to get appointments with Obama to talk about IFR reactors (and been rebuffed), so I probably don't need to be prosthelitizing them any longer.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
cheap electrical power available from nukes
That's not really true.
That's why I said it's a big "if", but in any case, the cost of nuclear power versus fossil fuels depends on how seriously you believe that there is a link between carbon emissions and global warming. Global warming could result in many trillions of dollars of damage as coastal areas are inundated by rising seas, droughts and other extreme weather, crop loss, etc.
If Nuclear power really does emit less carbon and carbon is causing global warming, then nuclear power could be far less costly even if the raw price per kwh is higher.
What did it cost you to move you and your family from the continental US to Alaska? How much energy was required? And what's different about the area around what's now your home since you took up residence there?
Now multiply that by 7 billion. Well... you did say *everyone* should migrate, right?
But they'll all get to smoke a joint without being hassled, so that makes it sensible. Yeah, right.
BTW, I live just as far north as you do. Also in a place where people don't pay much heed to the War On Some Drugs.
And yet... I'm pretty sure that you've managed to contribute little or nothing of use to the discussion here.
Il n'y a pas de Planet B.
With enough electrical energy we could convert to a hydrogen/oxygen economy, rather than a carbon-based one. There are some issues though, like the Hindenburg.
Then don't build your airship with a highly flamable skin - hydrogen was only part of the problem.
It turns out that Hydrogen in a normal Earthlike atmosphere is explosive.
So are many other common fuels like gasoline and natural gas, yet we've learned to harness them safely.
Also, it wants to be a gas rather than a liquid, which limits its utility.
As does natural gas, yet there's growing talk of using Natural Gas to fuel long haul trucks due to the dropping costs of natural gas.
And as a gas, it passes freely through any known material at room temperature because hydrogen2 molecules are as small as molecules get.
Generate it at the filling station so it doesn't have to be pumped for long distances, and dissolve it in some other substance to ease storage.
And then there's the whole "we get half of our electrical energy from coal" thing, and the conversion losses.
But the whole premise of this article is that we need to move to "clean" nuclear power, not fossil fuels.
Unless we get some good watts from some other source, your electric hybrid is likely generating more CO2 than my Chevy truck.
Unless your Chevy truck gets better than 53/48 mpg, then my electric hybrid generates less CO2 than your truck since both of our vehicles are powered by the same fuel - gasoline. Even when electric cars are powered by coal plants, they than conventional cars.
If I had an electric car, most of its power would come from hydroelectric power.
If power, from whatever source, was free, what would the world look like?
Learn to love Alaska
In addition to the other commentor's point about using nuclear power to extract, transport, and enrich fuel would allow you to dramatically decrease the carbon footprint of nuclear, there's also the points that:
2) Newer enrichment technology like centrifuges and, soon, laser excitation enrichment, dramatically reduce the energy needed to enrich uranium (which is a proliferation concern of course, but us keeping ourselves from having centrifuges doesn't seem likely to stop Iran from building them). I mean, the energy requirements for a gas centrifuge is something like 1/50 the power needed for the old gas diffusion plants (which were just horribly inefficient). I don't know what laser enrichment will be, but I gather it will use something like 1/100th the the power of gas diffusion facility.
3) If you use Thorium in a molten salt reactor, you don't need any enrichment at all (well, ok, you need startup fissile and for the first few decades, that probably means some enriched uranium or U/Pu mix, but eventually you can start new plants from the U-233 which was bred in old Thorium plants which will be being decommissioned, so you wouldn't need much Uranium mining at all), and it is currently a waste product of mining other minerals, so there's essentially no additional mining footprint (as demand grows, this may eventually change).
If power, from whatever source, was free, what would the world look like?
A whole lot brighter at night!
In the 1960's and 1970's, through the concerted efforts of well meaning organizations like Greenpeace, the nuclear power industry was destroyed. In their attempt to do good this organization indirectly caused the construction of untold numbers of carbon emitting power stations. In our current attempt to "do good" it is important not to let our hubris lead us to make mistakes that will cost future generations. No scientifically accepted model says the Earth with turn into a Venus-like desert. Average temperatures are expected to rise 2 - 12 degrees F by 2100 according to the EPA. Sea levels are expected to rise at most 2 meters by 2100 according to the IPCC. If it costs us a mere 1-2% of our GDP each year to prevent that change, over the course of 100 years that adds up: Current World GDP (About 64 Trillion USD) * 1.02 ^ 100 = $ 460 Trillion Dollars For $460 Trillion dollars we could move everyone within a mile of the ocean inland, build greenhouses to supply the entire world's food supply, and plant 100 billion trees with money left over.
Well, for one thing, our current approach to nuclear waste is completely moronic. Trying to bury it for 100k years is a bit of a fool's errand.
The only sane solution to the nuclear waste problem is to force the long-lived waste (mostly plutonium, but some other actinides as well) to fission, and the only way to do that is in a fast nuclear reactor.
In truth, we've painted ourselves into a bit of a corner. We NEED to do R&D on fast reactors (especially molten salt fast reactors, and the Integral Fast Reactor), and start to build whatever is going to be the safest, most effective nuclear reactor.
When you burn off the long-lived waste in a fast reactor, you do get more radioactive waste as output BUT that waste cools off "quickly" - it becomes basically non-radioactive after 300 years (I say "basically non-radioactive" because you do get extremely low levels of lingering radiation for a long time - that's how half-lives work, mathematically, but the radiation is lower than average earth crust after about 300 years).
I don't know about you, but I'd rather have a 300 year problem than a 100k year problem, wouldn't you?
Experience suggests that this is an oversimplification. The HTTR (High Temperature Thorium Reactor) had a few unexpected failure modes that led to some discharge of radioactive stuff into the atmosphere. The other german experimental Thorium reactor (Juellich) almost went boom because, for some nowadays not so mysterious reason, the graphite was heated way beyond what it should have. Nobody knew that back then. While nothing happened, it still is a mayor waste problem to this day.
This leads us to another issue. The failure mode of the HTTR was not that unexpected. It was, like the Tsunami issue at Fukushima, predicted by other people and ignored by those responsible. The designers and builders of the the HTTR made a point about how they were completely sure that nothing could possibly go wrong, and whoever claimed otherwise was an idiot. Doubts were brushed aside. The moral of the story is that we cannot trust the judgement of nuclear engineers to the extent that would be necessary.
"The design is inherently safe, nothing can go wrong" -- yeah, right.
Right - the problem is primarily due to an incremental increase in solar energy retention due to greenhouse gasses. Basically all of that 1361W/m2 ends up radiated back into space - some reflected, but mostly as infrared radiation (heat), but let greenhouse gasses capture even a fraction of a percent more of that infrared energy and it dwarfs humanities energy production and the global temperature will rise until it's hot enough that the amount of escaping energy again matches the incoming. Of course all manner of ecological feedback loops can contribute as well, and that's where the question really gets complicated. So far though it seems like, at the rate we're forcing the system, there are more positive (self-accelerating) feedback loops than negative (self-limiting), and that's a scary proposition for any engineer.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
It would be like magic, almost post-scarcity. Energy is *the* price setter. We tend to think raw materials and technology are more limiting, but actually more energy can substitute both raw materials and technology. For example, it is possible but energy inefficient to separate dilute chemicals.If energy is free, it would be possible to mine *everything* from waste and oceans. If you need a complex molecule, make an organic soup and separate useful stuff. If a certain production process has low yield, do not research ways to increase yield, instead increase capacity, separate, reuse. If farmland is not sufficient, use hydrophonic farms with artificial lightning and synthesized fertilizers. Need water, desalinate. Need water in the middle of Sahara, pump. Need cold air, condition. Make a dome over the a city o a desert; you don't need an impermeable dome if you don't mind using energy inefficiently...
Gentlemen, you can't fight in here, this is the War Room!
That's why we are talking about LFTR and not the reactor type you are refering to.
The german reactor was more or less a Uranium reactor that ran on Thorium as well. A LFTR runs almost purely on Thorium, needing Urianium only as a starter.
Do NOT mix the two up.
Please make yourself familiar with that concept. Thorium is a fuel. The reactor design is somewhat independent of it.
yes, nuclear is the answer.
Our culture has an irrational fear of nuclear power, much like in the early trains of steam trains, people thought they would die from asphyxiation if the train went too fast.
Some nuclear technology is dangerous. Thorium reactors (see other comments), for example, aren't.
But through our irrational fear, we've actually put us into a worse situation. In most western countries, we have nuclear reactors running well beyond their lifetimes, because we are too afraid to allow the construction of new, modern reactors. So instead we have old, less reliable, less safe and slowly falling apart reactors. Do you really think that's an improvement?
Burning coal and oil and gas is what has to stop, right now. I'm with a power company that offers renewable energy right now. But if there was one that offered renewable plus nuclear, I'd sign up immediately. For some reason, there isn't. You either get totally dirty power, with nuclear and fossil, or renewable. But nobody has the balls to ask the market if maybe there are enough people like me who don't really mind nuclear, but do mind fossil.
Assorted stuff I do sometimes: Lemuria.org
As others have pointed out, building and operating the plant has to be done regardless of the energy source, so factoring that in won't change much - though admittedly historically nuclear plants have been larger and more sophisticated. There's no reason that has to be the case though - the Hyperion reactor designs for example consist of a sealed reactor unit a few cubic meters in volume that produces 70MW of heat energy for ten years. The rest of the power plant could then be a retrofitted coal-fired plant for all that it matters. Well, aside from the underground vaults protecting the reactors from accident or sabotage, but that's just a big concrete-lined hole in the ground.
As for mining - a pound of U235 contains roughly 2.3 MILLION times the energy of a pound of coal. Even once we factor in the fact that only 0.7% of uranium is the readily fissile U235 isotope, and modern light water reactors (LWR) only extract about 0.6% of the available energy that's still about 100x the energy from a pound of mined uranium than a pound of coal. Refining it cuts even further into that energy budget, but still the shear reduction in the amount of "stuff" you need to move around should make it apparent that uranium has an edge in mining energy costs. And you can reprocess the "spent" fuel, which still actually contains most of the original U235 and improve that return considerably.
And things look considerably better for Thorium, 100% of mined thorium is the fertile Th232, and it "burns" much more efficiently without reprocessing - it has roughly 10,000x the energy density of coal, and at those levels it becomes painfully obvious how much lower the CO2 emissions from mining and transportation are. Plus it's a common by-product from rare-earth mining, so you get a fair amount for "free" in that regard.
As for handling the waste - with the exception of the spent fuel, which is all valuable isotopes and should be reprocessed anyway(in a LWR) or only moderate risk relatively short-half life isotopes in a Thorium reactor, the ash from a coal plant is actually more radioactive than anything coming out of a nuclear plant, as well as being highly toxic and far more voluminous. If we held everyone to the same environmental standards I suspect coal plants would have the higher energy footprint to deal with their waste.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Experience suggests that this is an oversimplification. The HTTR (High Temperature Thorium Reactor) had a few unexpected failure modes....
True. I was talking about Liquid fluoride thorium reactor however. It is simply not possible for this design to explode like Fukushima. When power is gone, the reaction cannot continue.
http://en.wikipedia.org/wiki/Liquid_fluoride_thorium_reactor
If I'd seen your post earlier, I might of modded you up.
At this point I'll concede on the global warming/climate change point. As you point out, the real question now is: Is avoiding the damage economically worth it? In some cases I hear people advocating to switching to electric sources that run 10X the cost of conventional ones.
As somebody else pointed out, if we were given a source of essentially free unlimited electricity we'd be 99% of the way towards post-scarcity. Cheap power enables so many things.
I think we still need a healthy mix of power sources, and I don't like coal due to the ancillary pollution - not just global warming. By the time you pilo on enough pollution controls to qualify coal power as 'clean', it's more expensive than nuclear.
We dearly need affordable power, and I think nuclear has the best promise. Even then I don't propose making it our 'sole source.' I like to place my ideal non-carbon electric mix at 40% nuclear, 20% solar, 20% wind, and 20% 'other' such as hydro. In order to reach this in the USA we simply need around twice as many nuclear reactors if we keep building them in the 1-1.4GW size range. We could use a whole raft of the small kw range devices for both providing electricity and heating remote Alaskan towns. Put the solar panels on roofs south of the Mason-Dixon line, the wind turbines in North Dakota and such, where they make sense.
I don't read AC A human right
Yes, it's science. The link between human carbon emissions and global warming is a model. It fits very well with the current data, including the estimations of past data (with the associated big error bars). However, new observations CAN invalidate the model, either with new data or better estimations of past data.
Be careful. It's science, not faith. It's a theory, just like relativity. It CAN be falsified by real data, just like Newton's gravitation was falsified in the large-field regime by Einstein. It's not a "settled" dogma.
That is exactly the type of claim I take issue with. If you are talking "gigawatts" and "can't blow up", then you are likely talking nonsense.
That's a very narrow definition of safe. It will most likely have its own way of making a mess. Perhaps it will be bloody unlikely in theory, but in practice, corrupt, greedy and stupid operators will make it happen.
Where he is wrong is in failing to realise that this only compares like with like. If I put a big electric motor in a Chevy truck and drove it like a redneck, it would possibly result in similar emissions to the Diesel version (there are benefits because the electric motor doesn't use power when stationary, and there is no auto transmission to waste fuel). But a hybrid isn't nearly as big and heavy as a truck, and it has much better aerodynamics. If I am transporting up to 4 people plus luggage, a hybrid is far more energy efficient than a truck. The problem is people who commute in overly large vehicles, for reasons of status.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
I'm not sure you understand what the tragedy of the commons is (it refers to common property that doesn't have a distinct owner, and as such is not taken care of). You certainly don't understand why it doesn't apply here.
Energy that is so cheap that it is easier to give it away than to sell it will be given away, while money is made from other sources. For example, the energy is so cheap that it might not be cost effective to charge households for its use, but you WOULD charge customers that use more than a certain amount (ie factories, large buildings, etc). This is similar to the way we treat roads now. Yes, we pay a gas tax, but commercial vehicles pay a use tax that is assessed by the mile. If roads were so expensive that they couldn't pay for the roads that way, then it would be more likely for roads to cost money to use for individuals.
I think a major mental block you are dealing with here is the fact that you aren't able to wrap your mind around the way that economies of plenty work. This is understandable because almost all real goods are governed by scarcity economics. Luckily, we have created a realm that is governed by economics of plenty--the internet. Think about the way internet services are provided. Free email. Free websearch. Free porn. Free everything. Yet the services continue to be provided, even by big companies that use expensive infrastructure. There would be nothing to stop a company like Google from providing free power to consumers if they could do it effectively.
FYI: The Bulletin of the Atomic Scientists is a noted anti-nuclear publication. Their name comes from long ago when a number of atomic scientists put it out to oppose nuclear weapons.
This is like having the RIAA do a review on the future outlook of The Pirate Party,