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PostPosted: Oct 22, 2008 9:57 am 
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Nuclear power won't solve America's reliance on fossil fuel imports
There isn't enough uranium to supply all the reactors that would be needed

21 October 2008
Daniel B. Botkin
International Herald Tribune

NEW YORK

John McCain has called for building 45 new nuclear power plants by 2030 and 100 eventually. Barack Obama's website says, "It is unlikely that we can meet our aggressive climate goals if we eliminate nuclear power from the table."

But to what extent can nuclear power really help reach energy independence?

There's a problem about nuclear energy that gets little attention. At present, fossil fuels provide 87 per cent of the world's total energy, while nuclear power plants provide just 4.8 per cent. (All nuclear power plants currently generate electricity, accounting for about 15 per cent of world electricity generation, while fossil fuels produce almost 67 per cent of the electricity.)

The best estimates put the amount of uranium that can be mined economically at 5.5 million metric tonnes, and according to the International Atomic Energy Agency, today's nuclear power plants use 70,000 metric tonnes a year of uranium. At this rate of use, the uranium that could be mined economically would last about 80 years.

Suppose it were possible to replace all fossil fuels with nuclear power. Suppose that we could use nuclear energy to make liquid and gas fuels to power vehicles and could do this quickly using conventional nuclear power plants.

We would have to build enough plants to increase energy production by 17.4 times, which means using 1.2 million tons of uranium ore each year. At that rate of use, the reserves of uranium would be used up in less than five years.

Geologists also estimate there are 35 million tonnes of uranium out there, regardless of the cost of mining it. With nuclear power replacing all fossil fuels, even these would be used up in 29 years.

Thus, if the goal is to counter global warming by replacing all fossil fuels with nuclear power, this goal cannot be met.

Advocates of nuclear power point out that it doesn't have to replace all other sources of energy. Let's consider that approach.

At a recent meeting, the Group of Eight major industrial countries agreed to reduce carbon emissions 50 per cent by 2050. Suppose nuclear energy increased just enough each year to enable fossil-fuel use to decline at a constant annual rate, to 50 per cent by 2050, while nuclear power therefore increased to provide 50 per cent of the world's energy.

At this rate of use, uranium reserves would run out by 2019, and the estimated maximum of 35 million metric tonnes of uranium in identified resources would run out by year 2038, gaining us less than two decades.

There are some important caveats. Exploring for minerals is done on an as-needed basis, and large areas of the world may have been little explored for uranium. Every mining geologist and mine corporation executive will tell you that estimates of total reserves of a mineral are just that -- estimates -- and that the reserves of many minerals always increase over time.

This approach may be all right for the planning time of mining companies, but it won't work for a long-term global energy strategy based on adequate supplies of uranium.

Considering the enormous costs of building the large number of nuclear power plants that are contemplated to replace fossil fuels, the U.S. would be courting disaster if it chose this route with nothing but blind faith that there may be a lot more uranium out there if we only look for it.

We need to know a lot more about available uranium resources and where they are. If they are in unfriendly countries, they might not be available at all.

Nuclear power advocates also argue that it is possible to recover significant amounts of uranium from spent fuel. According to the International Atomic Energy Agency, "In 2004, two-thirds of the uranium used was newly mined; the rest came from civil and military stockpiles, spent fuel reprocessing and re-enrichment of depleted uranium."

But the amount from spent fuels is not specified and a reprocessing program to deal with 1.2 million tonnes of used uranium would be a major undertaking, perhaps not technologically feasible in the near future.

Others suggest that breeder reactors, which produce more nuclear fuel than they use, will solve the problem.

The United States experimented with a few breeder reactors from 1964 to 1994, but they were shut down or work on them halted in the 1990s.

Other nations have tried building them and some are considering or developing them. But to my knowledge perhaps only one or two breeder reactors are in use and providing electrical energy anywhere in the world and these are probably not "breeding."

There are reasons for this: The technology is not there yet and the reactors are dangerous in themselves, even without considering their potential use in making atomic weapons. They are the kind of nuclear reactors that everybody fears Iran or North Korea might build and use to make atomic bombs.

In sum, the breeder-reactor route, if it is practical at all, is a long way in the future as a major contributor to the world's energy and certainly not a way to reduce our dependence on fossil fuels now.

The bottom line: From what is known about resources of uranium and the present and future state of nuclear power plants, there is no way that nuclear power can play a dominant role in the world's energy supply.

This is not to say that it could play no role in a strategy involving many kinds of energy, only that those who press for a greater role for nuclear power must first show that there will be enough uranium to assure that thousands of nuclear power plants built at enormous cost would not soon stand idle -- and leave our economy standing idle too.

Daniel B. Botkin is an environmental scientist. His latest book, Tomorrow's Energy: Fact and Fiction, will be published in 2009


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PostPosted: Oct 22, 2008 10:56 am 
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Geologists also estimate there are 35 million tonnes of uranium out there, regardless of the cost of mining it. With nuclear power replacing all fossil fuels, even these would be used up in 29 years.


He cant be much of a scientists if he doesnt even bother to dig up better information than that :roll:


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PostPosted: Oct 22, 2008 11:29 am 
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jaro wrote:
and according to the International Atomic Energy Agency, today's nuclear power plants use 70,000 metric tonnes a year of uranium.


:lol: :lol: :lol: :lol: :lol:


Last edited by USPWR_SRO on Oct 22, 2008 11:34 am, edited 1 time in total.

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PostPosted: Oct 22, 2008 11:31 am 
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This is a repeat of a standard and discredited anti-nuclear argument.


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PostPosted: Oct 22, 2008 12:14 pm 
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Daniel B. Botkin is an environmental scientist.

That usually means to me no credibility whatsoever.


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PostPosted: Oct 22, 2008 12:19 pm 
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dezakin wrote:
Quote:
Daniel B. Botkin is an environmental scientist.

That usually means to me no credibility whatsoever.

Ditto for me.

I just posted the article to show that this remains a popular argument -- claims to the contrary notwithstanding....


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PostPosted: Oct 22, 2008 1:32 pm 
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Botkin is a biologist with specializations in Ecology, Evolution and Marine Biology. He appears to know nothing about geology or nuclear energy. Knowing nothing never stopped a Green brom being an expert.
http://www.naturestudy.org/whois/botkin.htm


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PostPosted: Oct 22, 2008 1:36 pm 
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What is the annual usage from our 100+ reactors? And how much is in the ocean? I've heard people mention that you can still get uranium economically enough to run a power plant from ocean water, and that if we did so, uranium would outlive the sun. Are these opposite claims true?

That 70,000 metric tons per year is worded in a way that it looks like each reactor takes that, but do even all plants worldwide get up to that?


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PostPosted: Oct 22, 2008 1:57 pm 
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Well it's about 28 tons of Uranium per 1000MWe per year.

~445 Operating reactors worldwide of various sizes. Say all are 1000MWe units for simplicity.

28 x 445 = ~12500 tons annually with once through cycle. A lot of that is recoverable so amount used up would be even less with reprocessing.

Only a factor of 8-9 exageration in that article.


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PostPosted: Oct 22, 2008 1:58 pm 
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robertrichter wrote:
What is the annual usage from our 100+ reactors? And how much is in the ocean? I've heard people mention that you can still get uranium economically enough to run a power plant from ocean water, and that if we did so, uranium would outlive the sun. Are these opposite claims true?

That 70,000 metric tons per year is worded in a way that it looks like each reactor takes that, but do even all plants worldwide get up to that?


The 70,000 metric tons per year is correct but for worldwide consumption. U.S. would be about a quarter of that.

Getting uranium from seawater is a big question mark in my mind. The problem is the debate seems to always swing around to pro and anti nuclear points of view. I've seen as low as 300$ per kg from seawater to 100,000$/kg. Arguments around "peak uranium" have also become extremely polarized so it is hard, for me at least, to sift through the facts. I would love to get a better handle on things as I have become more and more enthusiastic over extremely simple molten salt designs without fuel processing that run as converters using LEU and thorium and only require a fraction of the mined uranium compared to LWR, HWR or pebble beds. If uranium reserves are anywhere near as bad as some make them out then there isn't enough for a large fleet of these even if they use less uranium (i.e. we'd need molten salt breeders).

David L.


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PostPosted: Oct 22, 2008 2:01 pm 
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USPWR_RO wrote:
Well it's about 28 tons of Uranium per 1000MWe per year.

~445 Operating reactors worldwide of various sizes. Say all are 1000MWe units for simplicity.

28 x 445 = ~12500 tons annually with once through cycle. A lot of that is recoverable so amount used up would be even less with reprocessing.

Only a factor of 8-9 exageration in that article.


Bob,

They are talking about the total amount needed. Only 28 tonnes goes into the reactor per year but that comes from 250 tonnes or so of natural uranium before enrichment. The depleted uranium is byproduct if we don't have breeders.

David L.


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PostPosted: Oct 22, 2008 2:31 pm 
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David wrote:
The depleted uranium is byproduct if we don't have breeders.

Yup.
There's that B-word again.
....only works in tandem with the R-word (reprocessing -- be it on-line or off)


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PostPosted: Oct 22, 2008 3:13 pm 
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The wikipedia article on uranium says there's 4.6x10^9 tons of Uranium in seawater. if 3.5x10^7 will last 80 years, 4.6x10^9 will last 10,514 years.
http://en.wikipedia.org/wiki/Uranium

It quotes the website of Japan's Atomic Energy Research Institute for actual numbers. A JAERI scientists developed a coating for cloth to extract the uranium from seawater. So, there's not just numbers, there's even a proof-of-concept industrial process.
http://www.jaea.go.jp/jaeri/english/ff/ff43/topics.html

Incidentally, the "economically accessible" numbers are very suspect as well. Most such
studies take the market price at the time of the report, and give the known extractible reserves at that price. At $60/Kg, far less uranium is accessible than at $600/Kg, and this price difference has a negligible effect on the cost of the electricity. Also, exploration or new extraction technologies can change the numbers dramatically.

Uranium is a common trace element in granite, limestone and coal. There are huge deposits of trace uranium through most of the U.S. and in most other ores and tailings. Given higher prices, deposits with several parts-per-million can be extracted using systems similar to trace gold mining. These deposits often have energy densities greater than an equivalent mass of coal. Uranium can also be economically extracted from coal ash. In many cases the Uranium in coal has more energy than the coal could chemically provide.


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PostPosted: Oct 22, 2008 4:10 pm 
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jaro wrote:
David wrote:
The depleted uranium is byproduct if we don't have breeders.

Yup.
There's that B-word again.
....only works in tandem with the R-word (reprocessing -- be it on-line or off)

You dont even need breeders, just surplus enrichment capacity. The depleted uranium isn't that depleted.


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PostPosted: Oct 22, 2008 4:26 pm 
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dezakin wrote:
You dont even need breeders, just surplus enrichment capacity. The depleted uranium isn't that depleted.


You're basically saying we need a better energy efficient enrichment process, as trying to deplete that uranium even more and end up with a product with the same enrichment as nowadays would otherwise be very energy inefficient.

dezakin wrote:
Quote:
Daniel B. Botkin is an environmental scientist.

That usually means to me no credibility whatsoever.


I'm also an environmental scientist, it just means that you're a scientist and care about the environment...unfortunately real scientist are stuck in their labs trying to find things never been found instead of badly rewriting stuff that are already known.


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