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autisticstar
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16 Feb 2008, 5:55 pm

I read an article this week about how many environmentalists have changed their position on nuclear power because of the prospect of global warming and the fact that nuclear power does not produce carbon emissions like coal and gas plants do. I don't have much of a background in science, but I think I remember reading about fusion and fission and one of these could potentially produce nuclear energy without the radioactive waste associated with nuclear power. Does anyone here know the difference between fusion and fission? What are your thoughts about nuclear power and alternative energy sources?



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16 Feb 2008, 6:18 pm

autisticstar wrote:
Does anyone here know the difference between fusion and fission?

Nuclear fission is used on modern nuclear power plants; it is chain reaction of uranium or plutonium decay induced by neutrons. But it produces very dangerous radioactive waste.
http://en.wikipedia.org/wiki/Nuclear_fission
Nuclear fusion is the transformation of light nuclei to more heavier (e.g. hydrogen to helium). It doesn't produce radioactive waste, but there is no fusion power plant now. Fusion is going inside Sun and when the "hydrogen" (fusion) bomb explodes.
http://en.wikipedia.org/wiki/Nuclear_fusion

I think that nuclear fission is more realistic perspective in the nearest future. If reactors on fast neutrons become more widespread, the deposits of nuclear "fuel" will serve us during 50000 years. But fusion is much more attrative, because it is the unlimited source of energy (from heavy water).



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16 Feb 2008, 6:24 pm

My problem with nuclear power is whilst its dressed up as our saviour once the oil runs out no-one ever tackles the problems with nuclear power outside of the radiation based issues.

You still have to build the stations - requiring all that comes with it quarrying etc - send boats out to ferry back ore to make fuel to use in your nuclear power stations then once its all over work out a way to distmantle it and build another. All producing copious amounts of greenhouse gasses and much of it requiring some non-clean fuel source.



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16 Feb 2008, 6:27 pm

actually fusion does produce radioactivity, just nothing like fission. There have been efforts to create a fusion reaction that produces more energy that it takes to create fusion; they're still a few decades off.

I used to work at a nuclear plant, and they had to refuel every couple of years. Still, they don't produce much in the way of greenhouse gases. There's no such thing as producing energy without a cost. But that's life..;)



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16 Feb 2008, 6:33 pm

Nuclear fusion as a practical fuel source is impossible because of the heat involved- no material in existence can withstand the temperatures produced. It is possible to contain the reaction with a magnetic field, but this requires so much energy that the fusion reaction is no longer viable as an energy source. Fission, on the other hand, produces large amounts of cheap energy and only a relatively small amount of dangerous waste which could be stored in a remote area or even jettisoned out into space. However, I think the best solution would be to use hydrogen fuel cells. Clean, efficient, the only waste produced is water... Chevrolet is starting to introduce a car running on fuel cells, and NASA has long used them for rocket propulsion. Why not use it for our general power demands?


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Stevopedia
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16 Feb 2008, 8:03 pm

Orwell wrote:
Nuclear fusion as a practical fuel source is impossible because of the heat involved- no material in existence can withstand the temperatures produced. It is possible to contain the reaction with a magnetic field, but this requires so much energy that the fusion reaction is no longer viable as an energy source. Fission, on the other hand, produces large amounts of cheap energy and only a relatively small amount of dangerous waste which could be stored in a remote area or even jettisoned out into space. However, I think the best solution would be to use hydrogen fuel cells. Clean, efficient, the only waste produced is water... Chevrolet is starting to introduce a car running on fuel cells, and NASA has long used them for rocket propulsion. Why not use it for our general power demands?


How do fuel cells propel rockets? Fuel cells only produce electricity.



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16 Feb 2008, 8:09 pm

Never say "impossible". Fusion probably needs a "trick" to make it viable.

As for "fuel cells"... would you care to say from whence you get the energy to get the hydrogen?


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Orwell
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16 Feb 2008, 8:30 pm

Stevopedia wrote:
How do fuel cells propel rockets? Fuel cells only produce electricity.

Sorry, I misspoke there. I was thinking of the liquid hydrogen fuel that was burned in rocket engines. They do use fuel cells for their power needs, though.

To lau... hydrogen is the most abundant element in the universe. A bit harder to get here on Earth, but its supplies are certainly much more plentiful than those of petroleum. Where do we get the energy to drill for oil or mine for coal?

One specific method that has been proposed is to use solar energy to split water into hydrogen and oxygen, and then use that hydrogen in fuel cells. With recent advances in solar cells, this is likely to become much more economical in the near future.


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jonk
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17 Feb 2008, 5:43 am

First off, global warming is a serious problem and we are at or quite near some important tipping points. We need to radically change how we use/produce energy. That won't be easy, as I'll start to explain here.

Worse, and much more difficult, we are going to have to come to grips with the idea of finding out how to run civilizations that have stable, not growing, populations. It's never been done before, all civilization has depended upon age distributions distorted by an exponential growth curve. No one really knows how to run one over the long term that has zero or negative growth. There are countries, like Italy for example, that experience periods of negative growth for periods of time but even then they import youth labor or else experience difficulties. The world's population has almost tripled in my short life time. And I've lived about half of it. Currently, the sheer mass of humans and their domesticated animals (cows, for example) has crossed beyond 99% of all of the mass of land vertebrates and we are consuming renewable resources at a rate that is at least 1.3 times the rate at which the earth replaces them. That's just the renewable parts and doesn't count the non-renewable forms, such as oil and coal. Total world forest systems are at 70% their equilibrium size a few centuries ago. World population is expected to rise from the current 6.65 billion, despite a drop from the peak growth rates experienced in the 1960's, to over 9.5 billion in 30-35 years (which I will live to see, easily.) It simply cannot continue. We will either figure a way to handle it intelligently and more gradually or else the problem will seek it's own solution precipitously. There is no other future possible.

Back to the power issue.

We don't find H2 in our atmosphere, like we do Argon for example, because H2 has such a low mass that it eventually reaches escape velocity and leaves into space. So it needs to be cracked off of something else. And that takes energy.

Currently, the commercial production of H2 in the US, at the rate of about 9 megatons a year, comes from fossil fuel. A steam reforming process, followed by a water gas shift reaction, is used. Each of which produces some hydrogen and a lot of the greenhouse gas, CO2. The net equation after both reactions is that one C(n)H(2n+2) fossil fuel molecule is added to (2*n) of H2O and produces (n) CO2 plus (4*n+2) of H2. You can see that a lot of CO2 is released. The reaction uses fossil fuels, but in addition to the fossil fuel use and the release of CO2, it also requires some 37 MJ/kg-of-H2 external energy input that has to come from somewhere. Usually, electrical, the source of which is often just a coal-fired plant producing more CO2. So the H2 has already cost a great deal in CO2 release and some energy.

The DOE estimates that in the US, if hydrogen vehicle targets for 2040 are to be met, the US will require 150 megatons a year of H2 (hydrogen) -- nearly 17 times what is currently produced, today. And today's process uses fossil fuels. There are a few non-production level methods being experimented with, but none seem viable before 2040. Some of these are a nanoscale version of a photovoltaic+electrolysis process (strictly lab-only idea, right now), biomass+microbial (also in a research stage and showing no promise by 2040), and biomass+thermochemical -- same comment. In any case, though there continue to be interesting innovations in photovoltaics, those today and likely before 2040 are very energy-expensive to make and can take a decade or more before they pay back their own manufacturing energy cost, let alone start providing energy for H2 production. Some microbes can use H2 for cell growth and also release it – but making gaseous H2 commercially this way is still far away. Not by 2040, for sure. Which brings us squarely back to basic electrolysis.

Electrolysis is about 65% efficient. A recent DOE report I read suggested the idea that it may be possible to crank that up to about 70% by 2040 -- that's their stated goal, anyway. So maybe so. But we don't know how, just yet. But using the 70% figure, it will require about 190 MJ/kg-of-H2. (Compare that with the 37 MJ/kg-of-H2 in the current production level means used for H2, that requires fossil fuels.) To reach the DOE's 2040 goal of 150 megatons/yr of H2, using the 190 MJ/kg figure, it will require some 25 quads of energy. That is 25*10^15 BTUs. That's 25% of all the energy used in the entire US from all sources. And take note that we only produce 7% out of renewables, 8% out of nuclear. If we don't want to increase the use of fossil fuels in making H2, and want to rely on nuclear power, we'll have to seriously expand our full-power operating plants to get there.

For example, there are 132 FPO permits (full power operating permits) and 28 of them are shut down (such as Trojan in Oregon.) This leaves 104 FPOs supplying 787 billion kilowatt-hours or 2.68 quads of useful energy after plant use is subtracted from the generation. If we decided to ramp up nuclear power to meet the projected 25 quads of electrical energy needed to make H2 via electrolysis, that would mean an additional 970 FPO permitted nuclear plants -- and that assumes that we continue building the huge monster-sized plants (10 CFR Part 50) we used to build in days gone by and not the smaller "advanced reactors" (10 CFR Part 52) that the NRC has been pushing since the early 1990's. We only have 104, right now.

Imagine setting about to do that? And the waste? Still an unsolved issue, with battles being fought in Nevada. In any case, it is doubtful that we will ever see another 10 CFR Part 50 plant set up in the US. It's been difficult enough for Congress to re-enact the Price-Anderson Act and the capital just isn't going to flow that direction -- it's simply dead. And the NRC is pushing the advanced reactors, 10 CFR Part 52, and they are very much smaller in scale (10 times smaller) and would require that many more to meet the need. So we aren't talking about 10 times as many plants as we have, we are talking about 100 times as many. And a lot of new infrastructure to build and maintain them. And doing it before 2040?? Not a chance.

(By the way, if you are being sharp, you may notice I gave figures for nuclear power that was 8% of about 100 quads. That should be 8 quads, roughly. But above, I've also mentioned the exact figures for the electrical energy generated by the 104 plants and it was 2.68 quads. You should wonder... what is going on here? Well, it turns out that conversion losses, transmission line losses and power plant usages reduce each one quad to about 1/3 of a quad -- we lose 2/3rds of each electrical quad we make!! Electricity is a VERY HIGH VALUE form of energy. It costs us dearly to make.)

Wind? That's a laugh. Hydro? Nothing left to do -- it's all been done and there will be no increases from there.

Which gets back to ... you guessed it ... coal. Which means CO2 and means global warming and means... death.

Now let me get to some of the details about licensing nuclear power in the US. I've been involved to a small degree, some years back. We have a serious problem regarding how to set up a human system around nuclear power plant licensing, so that the technical issues are well vetted through effective and knowledgeable debate. I've seen how the walls go up and the protective ring of moats get placed to form battlements against meaningful discourse in the US.

Years back, during the congressional hearings over the FPO (full power operation) permit for Seabrook, I found out about a MOA (Memorandum of Agreement) between the US NRC (Nuclear Regulatory Commission) and INPO (Institute of Nuclear Power Operations), which is (or was then) a private corporation that can be hired by nuclear power operators for tasks such as investigating nuclear power plant safety deficiencies.

Naturally, I have a copy of the MOA. This revised MOA was dated in October of 1988, was a modification of a 1985 MOA, and was signed by Victor Stello, Jr, then the NRC's Executive Director for Operations. I have carefully read through it and it effectively transferred the NRC regulatory responsibilities to INPO, because the NRC agreed not to duplicate safety investigations that INPO had performed and to rely upon those reports, instead. This was touted in the MOA supposedly to "lessen the burden" on the NRC. But the true (and intentional) effect of it was to cause nuclear power operators, upon notification by the NRC of some intended safety evaluation per their responsibilities, to immediately hire INPO, instead, to perform exactly the same required safety deficiency investigations that the NRC was expected to perform. Since INPO documents were private between INPO and the licensed Operator of the plant, and since the NRC would then refuse to duplicate the efforts, this MOA effectively sealed out of public view any safety information. In my opinion that was it's primary purpose. There is no doubt in my mind that this effect was well understood prior to the signing of it.

The upshot of this fact became QUITE CLEAR through the hearings and testimony I listened to for many, many hours, at that time. In the Seabrook case, the INPO documents were leaked and they highlighted several serious safety issues. In this specific instance, the leaked INPO documents described a wide variety of serious safety deficiencies (no one is arguing that INPO's work is poor.) The plant operator, PSNH, clearly planned to initiate corrective actions on the basis of this INPO report, but the corrective actions were planned to take substantially longer than the date on which the NRC's FPO permit was to take place -- March 1, 1990. In the testimony I listened to, NRC representatives were allowed onto the Seabrook premises to examine the INPO report, but were specifically barred from taking copies of the reports off-premises or from talking about any of the details in the reports. And in their testimony, they did in fact refuse to discuss the details and claimed that they had no copies to examine. They refused to address the leaked version. And the NRC consistently stated that the Seabrook plant met their safety requirements, without being willing to deal with any specifics. They expressed an opinion and refused to engage in any debate over the issues, hiding behind their MOA with INPO and behind their requirement for honoring their agreement with PSNH (Public Service company of New Hampshire.)

This kind of situation that effectively works to bar informed public discourse about plant safety cannot be acceptable if this is to proceed. We need open information so that those less directly benefiting from the business outcome and yet still better informed about nuclear power plant operations can make reasoned arguments on the basis of the better information available.

Here in Oregon, I was supportive of our own Trojan nuclear power plant, as I had at least some confidence in the staff operating the system and a fair degree of confidence in the corporation, as well. But I also got a first-hand chance to see, because I attended the public hearing where this happened in front of me, how they would pile hundreds of boxes of material out in response to an order to provide certain detailed information and only say, "It is in there, somewhere. We've complied with the law in providing it." But with tens of thousands of pages of useless writings to pour through, it was very time consuming to track down what they were supposedly providing. And it made life for those seriously trying to understand the issues from an outsider point of view quite painstaking. And, of course, that was the intention at the outset. They were forced to cooperate, by law, but they used every available avenue they could to make it more difficult on those who might question them.

Now, I also understand how I might get like that, too, under the constant onslaught from people who largely don't know why they might legitimately oppose a system or otherwise why they should support it, but who are enabled by law to make the nuclear power business more difficult. But when the whole process becomes nothing more than diametrically opposed camps with no common ground between them, I fear for sensibility on any side. And that just isn't good.

The US nuclear power industry has also enjoyed powerful friends in various congresses and in various administrations (such as at the NRC) and has had the Price-Anderson act enacted and re-enacted in order to insulate them from any real or perceived risks in power plant operation.

Some years ago, I secured the proposed rules from the NRC on advanced reactors. In them (I still have the lot of them in some boxes in my closet), the NRC proposes to standardize the licensing, providing early site approval, certification of plant designs by rule (avoiding the lengthy public hearings for each plant), and simultaneous issuances of both a construction permit and an operating license (a "one-stop licensing called "combined licenses".) I'm not opposed to some aspects of this, as I understand the need for efficient processes to get the job done. But the rules have/had all the appearances of just more of the same, similar to the NRC MOA with INPO.

Under these provisions, nuclear power plan designs can be simply certified by rule. The cert is valid for 15 years from the date of issuance. An application can be renewed for another 10-15 years. If a utility takes full advantage of the procedures, securing an early site permit in advance and referencing a certified standard design in its combined license application, the issues available for consideration in any public hearing is severely limited. Neither the suitability issues nor the reactor design issues can be litigated or discussed. (The suitability is decided simply by the issuance of the early site permit and the reactor design issues decided by the existing certification.) The effect is to eliminate any safety siting issues in combined license hearings, even if there is new material information discovered _after_ the issuance of the early site permit.

So. How to bring about an effective process? I think it needs to be adversarial, in the same sense perhaps that science processes are, where knowledgeable statements can be challenged by knowledgeable criticism, and where that criticism *MUST* be responded to and fairly dealt with. And back and forth. A consensus process needs to be in place. Differing views need to have a venue, but perhaps restricted to knowledgeable adversaries, so that the heat of the process helps ensure that the better approaches are chosen. Ultimately, we need a real discussion that addresses the legitimate and real concerns and finds an appropriate compromise we can all live well with and not just the rulemaking outcome of some back-room negotiations between a few of the interested parties.

What I do know is that the system in place today is only good if you are willing to place your faith in those with profit motives in the industry. The battlements have been built and are continuing to be built, against the possibility of dissent.

So nuclear?? Well... aside from the fact that we have never licensed or built a single one of the new style advanced reactors... aside from the fact that we don't have a good means of transportation and disposal of nuclear waste... aside from the fact that we need to set up a practical means for allowing informed criticism to operate... and aside from the fact that there is no insurance company in the world that will insure any of these plants without a Congressional "blank check" that absolves them of costs above some small, fixed amount (as the Price-Anderson Act does for earlier plant types)... aside from the fact that we need to build 100 plants more for each plant we have running... well, aside from those problems, they sound pretty good.

So... where does this leave us, exactly?

My opinion? Deep s**t. There is NO easy answer here. We are stymied at every turn. Coal/fossil fuels are the only __easy__ answer to anything, we will probably not find the stamina to do anything else before it is far, far too late, and even then we won't have it because the turn-around costs will be quite simply impossible, and we will pass a couple of serious tipping points and the Earth will help us solve a few problems for us but not exactly in a way we will find pleasant.

Jon


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Last edited by jonk on 17 Feb 2008, 2:37 pm, edited 1 time in total.

hyperbolic
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17 Feb 2008, 6:08 am

I've been taking some industrial classes with people who are training to be nuclear plant technicians, and I have heard from some of them that you do get some radiation from the nuclear plants as an employee. If you get a certain amount, you are forced to retire. That was kind of scary.

I am also aware that the current storage operations in the US for nuclear waste are in a terrible state. It goes against security. The concerns of the state of Nevada over radioactive material being stored in a giant manmade cave at Yucca Mountain seem to overshadow the concerns of any major american city that a radioactive dirty bomb might be released over its population using American-manufactured radioactive material.

Until the storage issues can be resolved systematically, I am not really a fan of expanding nuclear power. Solar and wind seem much more green and still can be productive.



jonk
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17 Feb 2008, 7:23 am

hyperbolic wrote:
Solar and wind seem much more green and still can be productive.

First off, it's important to keep in mind how different electricity is from other forms of energy. Electricity has a very high cost to its production -- we waste 3 watts to produce 1 watt -- and it is the most versatile and valuable form we have. There are a million better ways to use that energy than heat, for example, or driving a car. Medical equipment comes to mind as a good example of a high valued use of a high valued energy, like electricity. This is neither here nor there regarding your above comment, but I say this because it is important to not equate electricity with other forms, such as gasoline.

Photovoltaic (one of the forms of 'solar') currently takes prodigious amounts of energy in manufacturing them. So much so, in fact, that many types will NEVER pay just their own manufacturing energy costs in their serviceable lifetime. They will break before break-even occurs. Most, though, reach that point a little earlier than _never_, but more on a scale of a decade or so. And in that time, some percentage of them break down and must be replaced. So it isn't so good, just yet. There are some very interesting technologies in the pipe -- but many of them have serious problems, such as requiring focusing or lensing systems or needing to "follow the sun." And of course, there is the cosine behavior of light energy per unit area on the Earth's surface, not to mention weather -- so some places are much better than others at reaching payback.

It's not very green, just yet. And not fieldable on a level that can serve a civilization, in any case.

Wind has a whole host of its own problems, but it is doable up to a point. I cannot imagine, though, how it will ever become a significant part of our 100 quads of energy per year (in the US ... the world is 400 quads.) It's not a solution to the problem, so far as I can tell.

If anyone thinks they can make a clear, quantitative argument regarding any "green" technology, I am ALL EARS. Seriously. I don't know, at all, how we can continue to consume anything close to the energy we currently consume, along with provisions for growth with population and business needs, without fossil fuels. No solution I can see is viable. They all have fatal flaws. And the fossil fuels will quite simply and fundamentally change the world as we know it. So we kill ourselves that way, too.

Conservation is always good for a thought. But if the average US citizen reduced their needs to 1/10th of what it is now, if they were to regress that far back into the horse-and-buggy days of more than a century ago and live like someone in Bangledesh, population increases in the world would take maybe two or three decades to completely get us right back to the same place in consumption of energy resources. Conservation is great. But it's linear and not exponential, like population growth. An exponential growth wipes out linear reductions in very short order.

Ultimately, it all comes back to population. We need to get down to a billion people, maybe two billion at the most. And reducing population does NOT seem like a solution that is politically feasible. And it cannot be voluntary, as then those with the genes which allow them to consider the idea seriously enough to act on it will expunge themselves from the gene pool leaving those with genes that prevent them from acting on such ideas to fill the void. And back to population rise.

So... anyone think that world-wide, mandatory population control is in our future?? Not I.

I just don't see an answer. Not when you get down into the details sufficiently to calculate reasonably accurate numbers.

Jon


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17 Feb 2008, 8:50 am

To quickly get them out of the way, Hyperbolic. 1) I lived in Cornwall for fourteen years. My radiation exposure there was way above what a nuclear plant worker is allowed to receive. 2) Storage of waste does seem haphazard. There are better ways - at present, I would favour dumping on one of our moons, say. 3) Alternatives such as planetary surface based solar/wind are not very efficient, at present.

And, Jonk, a massive and well thought out exposition. I agree pretty much whole-heartedly. I hope that the one thing you have missed out is the one thing that will get us through. That is: you assume science and technology will stand still.

Without some major changes in knowledge and/or approach, the future does look rather bleak. I hope that the pressure will build up enough to at least start using existing technology to better satisfy our demand for energy. For all its shortcomings, surface based nuclear energy is at least possible. Better would be orbital. A breakthrough in fusion would certainly be nice, if such a thing is indeed possible.


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17 Feb 2008, 11:37 am

Dr. Jerry Pournelle once proposed a perfectly workable, albeit non-politically-correct, method to dispose of fission waste products.

Step 1: Dry the waste.

Step 2: Mix the dried waste with concrete (or glass, but concrete is cheaper).

Step 3: Pile the bricks out in the middle of the desert - around one of the old nuclear-bomb test sites, perhaps. Cover the pile with a Quonset hut, to keep off the occasional rain. Don't sweat the shielding - the area's already radioactive, right?

Step 4: Put up a three-layer fence system around your site. On the outermost fence, every ten feet or so, place a sign reading, in English, Spanish, and a couple of other languages, "IF YOU CROSS THIS FENCE, YOU WILL DIE."

The sign isn't lying - go all the way to the building in the middle, and you'll be lucky to make it back out again before your hair starts falling...


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17 Feb 2008, 2:42 pm

lau wrote:
And, Jonk, a massive and well thought out exposition. I agree pretty much whole-heartedly. I hope that the one thing you have missed out is the one thing that will get us through. That is: you assume science and technology will stand still.

Not "stand still." For example, I accepted the US Department of Energy's estimate of a change in efficiency from 65% currently to 70% by 2040 for electrolysis. I just didn't assume any radically new developments that no one can see, right now. It's possible that there will be such a discovery, of course. But we don't have a lot of time left. Tipping points are being crossed as I write. Unless one of those happens in the next 5 or 10 years, it won't really make enough of a difference by the time these points are crossed irrevocably. So I set those aside, as unlikely to occur in time.

What makes this all the more personal, and this isn't just because I have children, is that I work with and teach other children and try and get them interested in science. I hear the anger towards "adults" who don't seem to care about them at all. And I don't know what to tell them. These are all our children. And even then, even when it is our own kids, those we supposedly care about more than life itself (or should), we can't even seem to get off of square one. It makes me wonder if there really is intelligent life anywhere in the universe. Not here, anyway.

Jon


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17 Feb 2008, 3:49 pm

Orwell wrote:
Sorry, I misspoke there. I was thinking of the liquid hydrogen fuel that was burned in rocket engines. They do use fuel cells for their power needs, though.
Chevrolet is starting to introduce a car running on fuel cells

It is very hard to have liquid hydrogen in a car - it is extremly cold and volatile. Compressed hydrogen is too penetrative and flammable. May be, some hydrides will help. Another good variant is ethanol but it is expensive and drinkable :).
But I see more effective and rational way for big cities - mass transit system; it is simpler to put hydrogen fuel tanks on bus (or even use trolleybus). It is possible to serve metropolis with 10 million citizens mostly by public transport (it was in Moscow 20 years ago). E.g. one metro line with 160 m long platforms, 90 sec interval between trains and 1,5-2 km between stations is more effective than highway and may be connected directly to the power plant without any fuel tanks.

Orwell wrote:
Nuclear fusion as a practical fuel source is impossible because of the heat involved- no material in existence can withstand the temperatures produced.

May be it is possible to develop really effective magnetic traps for plasma or even invent a catalyst which will allow to conduct nuclear fission at room temperature.



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17 Feb 2008, 5:04 pm

Alexey wrote:
May be it is possible to ... invent a catalyst which will allow to conduct nuclear fission at room temperature.

I think you mean fusion, as in cold fusion. Fission works just fine at room temperatures.

I've been closely following cold fusion discussions from a physicist point of view. The important physical laws and how they might apply to cold fusion are pretty well understood and, to be honest, were pretty well understood by the end of the 1950's. Nothing new has arrived that I'm aware of that changes the possibilities here. Not even suggestions of spin-2 bosons in superconductivity. It simply isn't in our near future -- near enough to make any difference at all in what lies ahead.

Physicists never bought into the idea, even at the beginning. The idea of cold fusion was cold dead in the physics community for a long time. Cold fusion caught the attention of chemists who, I have to say, would be pretty happy as a group to see the physics community with a bit of a bloodied nose. If you have any question about that emotional desire, just nine months after the announcement from Fleischmann and Pons, and in preparation for the annual meeting of the ACS, the physicists were actually barred from presenting there. The chemist community had come together on this subject and didn't want to hear dissenting voices, most especially _informed_ dissenting opinions.

Nothing much of real consequence has happened since to change the predictions about this. And in no way is it going to happen in time to make any difference, even if I'm wrong about the possibilities.

Jon


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Say what you will about the sweet mystery of unquestioning faith. I consider a capacity for it terrifying. [Kurt Vonnegut, Jr.]