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Costing the Earth, Wednesday -- new nuclear build
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mobbsey



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PostPosted: Wed Mar 23, 2011 12:55 am    Post subject: Reply with quote

An Inspector Calls wrote:
And here's a strange thing: your original article pleading the shortage of uranium fuel makes no use of the thermodynamic argument either


I wrote the article for the Oxford Institute for Energy Studies nearly six years ago; what do you think I've been doing in the mean time? Rolling Eyes


An Inspector Calls wrote:
No: you want to postulate a thermodynamic failure - you demonstrate it. Give us your numbers to demonstrate that uranium extraction will be thermodynamically limited in the not too distant future. I await your erudite reply.


Erudite? You really want me to be erudite? Shocked

Damn, I'll have to look that up first... err... ahh!
Quote:
"erudite" - (adjective) having or showing knowledge or learning.
Origin: from the Latin eruditus, from erudire "instruct, train"


Right, gotcha...


OK, let me take you right back to the first reply I sent and recap what my initial position was:
Quote:
"So, yes, I absolutely accept the THEORY of the extraction of uranium from seawater; what I doubt is the practical REALITY of being able to do that at a economic value that doesn't nullify the effects of feeding that energy into the global economy."


I accept that you can get the uranium -- what I doubt is the viability.


Now, for the purposes of this exercise I'm going to use life-cycle data from the World Nuclear Association (WNA), just in case you believe that anyone else might be a little biased in their weirdo-hippie green renewable outlook.

Goto: http://www.world-nuclear.org/info/inf100.html

The flaw in this analysis is that it's a truncated life-cycle assessment (basically, it misses a lot of things out) -- if you want a proper life-cycle analysis of the nuclear fuel cycle I suggest that you read either:
http://www.isa.org.usyd.edu.au/publications/documents/ISA_Nuclear_Report.pdf
or
http://www.energywatchgroup.org/fileadmin/global/pdf/EWG_Report_Uranium_3-12-2006ms.pdf
or
http://www.stormsmith.nl/

For example, the University of Sydney study states that, using lower grade (0.01%) uranium ores representative of the 30-50% of the world's remaining uranium reserves, "Under these conditions -- assuming Storm van Leeuwen and Smith’s parameters -- such a nuclear fuel cycle would indeed not produce net energy, and its greenhouse gas emissions would be comparable to a gas-fired power plant"; in contrast the WNA study just ignores the low quality ore issue.

That said, let's use the WNA's dodgy figures.


For a typical 1GW reactor, based on the WNA's 'Energy Analysis paper' statistics, the lifetime energy input is 52.5PJ (peta-Joules) of which uranium mining accounts for 2PJ, or almost 4% of the input energy. This produces 3024PJ of electrical power, meaning that the energy return of the plant is 98%, or 20:1 (that's nearly double the result of some other studies).

Now, running a 1GW plant for the 40 years in the WNA study uses 640kg of U-235/year; that's equivalent to 25,600kg for 40 years. The amount of natural uranium, composing 0.7% U-235, is therefore 3,657,143kg. Converting that to UO2, 4,929,193kg.

The trial you cited used 350kg of "braided amidoxime polymer". I don't have the embodied energy data for that, but I do have the figure for polyamide -- 140MJ/kg. The raw plastic has to be processed -- we can't know how much energy that took because it could be extruded, injected or blown, and all three have very different energy demands. Given that the plastic is burnt to reclaim the uranium metal, let's ignore the processing energy and assume it's balanced out by the energy recovery from burning plastic (that's a big "if" because of the low generation return of plastics incineration).

So, the amount of energy it takes to make the plastic, to absorb the amount of uranium, that a 1GW reactor requires for 40 years, is going to be the mass of uranium multiplied by the 350 kilos of plastic multiplied by 140MJ/kilo of embodied energy and then divide by a billion to convert to peta-Joules...
and the magic number is 241.5PJ

So, based on the WNA's same flawed fuel cycle analysis the total energy input is 292PJ -- five times higher; originally mining took 2PJ, which means your seawater scheme has increased the energy required for yellowcake production by a factor of 120!

You see, it's all about entropy!

Also, you've just completely distorted the price economics of the nuclear fuel, but -- and you're not going to like this -- the cost of the fuel has absolutely nothing to do with the uranium and everything to do with the plastic you're absorbing it onto.


Now, let's talk plastic prices (before we start, be aware that I started my working life as an engineer in the injection moulding industry).

Remember the embodied energy of nylon was 140MJ/kg. It's calorific value is only 45MJ/kg; so it embodies 3.1 times more energy than it contains. That's a representation of the extra energy that it takes to fabricate the plastic from monomers.

Let's assume all that energy is made of crude oil. To collect 1kg of uranium you need 350kg of plastic, so 350kg multiplied by 140MJ/kg and divide by 1,000 to convert to giga-Joules is 49GJ of energy. There are 5.7GJ of energy in a barrel of oil, so to create your 350kg of plastic takes (49/5.7) 8.6 barrels of oil.

So, finally, taking the current price of a (Brent) barrel as $115, your 1kg of uranium oxide is going to cost $989! Shocked
(and, of course, that doesn't include the price of installation, maintenance of the matrix, collection, handling, extraction, etc.).

Right then, here's you chance to get interactive and provide some feedback:

I can tell you the market price of nylon, $2,500/short ton (907kg), so 350kg of raw material at wholesale will actually cost $965. Isn't that a fairly good correlation to the energy value of the raw crude that went into making it!!

So, the quote you reproduced earlier stated:
Quote:
While more tests must be done, the researchers claim such a system could extract uranium at a cost of $200-300/kg uranium, two to three times the current cost at $100-150/kg. It has been argued that fuel is a small proportion of the cost of a nuclear power plant, so this increase will not drastically affect the cost of electricity.


OK, tell me, please, how do you square their figures being three to five times lower than the cost of the raw materials? -- and of course I'm only using the raw material cost, not the final yellowcake production figure! Laughing

Were they based on much lower oil prices (there's a pretty good correlation between wholesale plastic and oil prices) or were they just telling porkies to try and con the investors?

Now, of course, oil is worth $115/barrel. If oil went back to $147/barrel, as in 2008, your kilo of uranium would $1,264.


OK then: from your earlier quote -- "we could evidently afford to pay £1,000 per kilogram" -- that's exactly what you are proposing!

You're whole scheme would instantly push the cost of nuclear way up above current levels; which is why I suggested earlier that, from a thermodynamic perspective (or "economic entropy" as Nicholas Georgescu-Rogen called it), the higher the entropy of the source material the higher the energy input and costs.

...and finally, as the great Samuel Pepys said (or was it Zebadee?), "and so to bed".
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An Inspector Calls
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PostPosted: Wed Mar 23, 2011 10:14 am    Post subject: Reply with quote

From The WNA I read, in terms of energy balance:
Input is thus 1.74% of output.

And note that the input the WNA considered
Fuel preparation: mining, milling, conversion, enrichment, fuel fabrication,
Power station: build, operate and decommissioning, and finally
Waste management.
But as you say, rather limply because you don't say how,'this is a truncated life cycle'!!

So OK, next, the University of Sydney which is one of your examples of a proper lifecycle:
http://www.isa.org.usyd.edu.au/publications/documents/ISA_Nuclear_Report.pdf
And here we have:

The energy payback time of nuclear energy is around 6½ years for light water reactors, and 7 years for heavy water reactors, ranging within 5.6 14.1 years, and 6.4-12.4 years, respectively.

Now in both of these examples they're looking at the thermodynamic efficiency of the whole nuclear lifecycle, inclusive of fuel.

Next, let's switch to looking at the seawater extraction example. There they extracted 1 kg of uranium using a suspended array of filters. You assume a mass of 350 kG [sic] costing 140 MJ/kg to produce - i.e. 49 GJ (I think you're doing a whole reactor/annum calculation, but I'll stick with my measly 1 kg of uranium produced). Now 1 kg of uranium needs conversion from cake to fuel and I'll leave that energy calculation as an exercise to you, but roughly 1 kg of uranium fuel at 5 % burn in a 30 % efficient reactor (Hoyle's example) produces 300,000 kWh, or 1.08 TJ.

That means the energy output is 22 times higher than the energy input
You see, it's all about entropy!

As you've stated an energy cost for the polymer of 350 MJ/kg I see no point in drilling down to explore the components of that figure and how many barrels of oil that takes - interesting but I assume your energy figure of 140 MJ/kg includes that as you're obviously very aware of whole-lifetime energy costs.

So, I think you've completely failed to demonstrate the weakness of the uranium extraction fuel cycle.

And finally

Quote:
OK then: from your earlier quote -- "we could evidently afford to pay £1,000 per kilogram" -- that's exactly what you are proposing!

You're whole scheme would instantly push the cost of nuclear way up above current levels
That's nonsense. There's no proposal, as you put it, merely a sensitivity calculation. To remind you, Hoyle assessed the impact of $1,000/kg uranium fuel as a fuel cost value of 0.33 p/kWh.

Last edited by An Inspector Calls on Wed Mar 23, 2011 2:05 pm; edited 2 times in total
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mobbsey



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PostPosted: Wed Mar 23, 2011 11:10 am    Post subject: Reply with quote

An Inspector Calls wrote:
Now 1 kg of uranium needs conversion from cake to fuel and I'll leave that energy calculation as an exercise to you, but roughly 1 kg of uranium fuel at 5 % burn in a 30 % efficient reactor (Hoyle's example) produces 300,000 kWh, or 1.80 TJ.


No it doesn't.

You're equating you're 1kg uranium dioxide seawater yield, with only 0.7% U-235, with a "5% burn-up in a nuclear reactor" which is going to require at least a 4% to 5% U-235 enrichment (depends on levels of Pu breeding, which depends upon reactor configuration).

Consequently the amount of energy from your 1kg of seawater UO2 is going to be...
(92/(92+16+16)) = 0.74 -- to correct for U - UO2 mass
multiplied by...
0.007 x ( 5% / 0.7% ) = 0.00098 -- to correct for U-235 enrichment

...which means your final energy value would be 1.8TJ x 0.74 x 0.00098 = 0.0013TJ, or about 0.07% of what you thought it would be originally. (and that's before we even get started on subtracting the energy costs of the nuclear fuel cycle!)

In any case, I asked you to comment on why the research study you quoted produced figures for uranium costs which were three to five times less than the cost of the raw materials to produce the plastic braid. Have you no views on that at all?
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biffvernon



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PostPosted: Wed Mar 23, 2011 11:43 am    Post subject: Reply with quote

mobbsey wrote:

You're equating you're 1kg uranium...


Ha! At last! A fault in a mobbsey post. Second 'you're' should be 'your'.
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mobbsey



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PostPosted: Wed Mar 23, 2011 11:55 am    Post subject: Reply with quote

biffvernon wrote:
Ha! At last! A fault in a mobbsey post. Second 'you're' should be 'your'.


Perfect is for Gods and megalomaniacs, my imperfections demonstrate my humanity... ah yes, good 'ole Alexander Pope -- "To err is human, to forgive is divine".
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An Inspector Calls
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PostPosted: Wed Mar 23, 2011 1:44 pm    Post subject: Reply with quote

You're far too pessimistic for the enrichment process.
Referring to this article:
http://www.world-nuclear.org/info/inf28.html

Quote:


The capacity of enrichment plants is measured in terms of 'separative work units' or SWU. The SWU is a complex unit which is a function of the amount of uranium processed and the degree to which it is enriched (ie the extent of increase in the concentration of the U-235 isotope relative to the remainder) and the level of depletion of the remainder. The unit is strictly: Kilogram Separative Work Unit, and it measures the quantity of separative work performed to enrich a given amount of uranium a certain amount. It is thus indicative of energy used in enrichment when feed and product quantities are expressed in kilograms. The unit 'tonnes SWU' is also used.

For instance, to produce one kilogram of uranium enriched to 5% U-235 requires 7.9 SWU if the plant is operated at a tails assay 0.25%, or 8.9 SWU if the tails assay is 0.20% (thereby requiring only 9.4 kg instead of 10.4 kg of natural U feed).
So instead of getting 1.08 TJ of energy out of my kilogram of uranium cake, I get 135 GJ of electricity.

Next, the energy involved in this enrichment process (same reference):
Quote:

The gaseous diffusion process consumes about 2500 kWh (9000 MJ) per SWU, while modern gas centrifuge plants require only about 50 kWh (180 MJ) per SWU
Taking the latter figure, 8 SWU will require 1.44 GJ.

Therefore 1 kg of seawater uranium cake will produce 133 GJ.

The sea filtering process took 49 GJ, so the energy multipication ration is now down from 22 to 2.7.

Which is obviously about right as we're dividing the usefulness of the cake by 8 in order to get it into a reactor. In case you want to nit-pick over the SWU of 8, feel free, but then I'll claim 40 % efficiency for modern nuclear power stations.

Let's deal with this point of yours now:
In any case, I asked you to comment on why the research study you quoted produced figures for uranium costs which were three to five times less than the cost of the raw materials to produce the plastic braid. Have you no views on that at all?

That is easily dealt with. There are two explanations:
(a) a change in oil price will obviously affect their costings, and, much more importantly
(b) the filtration material can be recycled and thus used for many collection cycles.

Let's consider point (b) and not hide the virtues of this process, suppose the material can be reused 5 times, which would get the costings nicely correct.

The energy efficiency of the process now goes up to 13.6.
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mobbsey



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PostPosted: Wed Mar 23, 2011 2:27 pm    Post subject: Reply with quote

An Inspector Calls wrote:
The sea filtering process took 49 GJ, so the energy multipication ration is now down from 22 to 2.7.


OK, not bad, but any process that has a return low than 4:1 is barely economic -- for example tar sands production, which comes into the range of 10:1 to 6:1 (barely makes a profit as $90/barrel, and they've hit capacity bottlenecks even at that price). The basic issue is that the process has to create a sufficient excess, or in strict terms a thermodynamic potential, to make the rest of the system work (have a read of Nicholas Georgescu-Rogens, 'The Entropy Law and the Economic Process' -- it was a book that was thirty years ahead of its time, and now gets mentioned in all the latest energy and resource economics research).

And, don't forget, I didn't include the energy required to prepare the plastic braid, put it in place and maintain it and then harvest the metal. That's likely to erode your 2.7:1 even further

An Inspector Calls wrote:
(b) the filtration material can be recycled and thus used for many collection cycles.

Let's consider point (b) and not hide the virtues of this process, suppose the material can be reused 5 times, which would getting the costings nicely correct.


Can you point me to any research that says the plastic matrix can be reused? All the studies I've seen burn the plastic in order to recover the metals collected because that's the most efficient way of doing it. You could dissolve the plastic using a solvent and enzymes, and try and concentrate the metals, but then you'd have to re-manufacture the plastic which will require about the same value of energy debt.

The plastic is purely a one-time process -- at best you're going to recover electricity and process heat from burning the plastic, which is why, if you re-read, I discounted the energy to process the raw plastic on the grounds it might be a similar amount of energy to the electricity produced by "thermal recovery" (to use the industry euphemism).

So, I can't give you the efficiency savings point.

Also, have a read of the University of Sydney study in detail... it's rather good because they consider all the critiques of nuclear fuel cycle LCA as part of their review!
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An Inspector Calls
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PostPosted: Wed Mar 23, 2011 3:05 pm    Post subject: Reply with quote

So, at last you concede that the process does not fail thermodynamically!

Quote:
Can you point me to any research that says the plastic matrix can be reused?


The original research paper (Kanno) talked of the adsorbant material being "robust". There are now papers pointing to the adsorbant being fixed as a continous belt suspended in an ocean current - and such systems recovering 6 tons per annum. And then there are (French) papers that propose using no adsorbant but instead nano-filtration. It takes no effort to find these papers using google and it's left as an exercise.

And just to go right back to the beginning of this discussion: the reason I made an example of seawater extraction was to highlight that as this was perhaps the lowest concentration of uranium we know about, and if we can extract that economically and thermodynamically efficiently, then when we consider other sources, it was highly likely that they were also viable for economic extraction - given an increase in the price of uranium cake. And I've demonstrated, that uranium price hike was unlikely to make nuclear power uneconomic.

So: nuclear power is not going to fail through any lack of fuel - probably ever.
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mobbsey



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PostPosted: Wed Mar 23, 2011 5:28 pm    Post subject: Reply with quote

An Inspector Calls wrote:
So, at last you concede that the process does not fail thermodynamically!


You seem to view the thermodynamic process as a profit/loss account where anything above 1 if good; it's not.

As I said previously, you need to make a significant excess of energy output over input in order to drive the economic process. For example:
# a system has an energy return of 20:1;
# the grid might drop 10% of throughput, 18:1;
# then power conversion and distribution in industrial processes can lose a further 20%, 14.4:1;
# then something like an induction heater, or a geared electrical motor drive, might operate at 60%, so the delivered work is 8.6.

And so of your original 20:1 it's only 8.6 that goes into adding value to the resources that drive the economy. If the source ratio were 10:1, we'd be talking half that being delivered; 5:1 a quarter, etc. This isn't an issue of simply providing an energy supply, you have to provide a sufficiently large enough supply to overcome the entropy of the materials -- from raw materials that need processing, and components that need assembling, through to the pollution that needs to be cleaned/abated -- in order to create value.

What makes the economy operate isn't simply money, it's the ability to deliver "order" to resources and in turn this creates value. You take raw materials and turn them into something valuable; that principle doesn't differentiate between a steel smelter and a production line for Barbie dolls -- you still have to put in the energy to create the value of economic output. A half the value of economic growth is the value of raw energy added to the economy; a further 20% of economic growth is created by energy efficiency improvements; capital and labour constitute the final 10% and 20% respectively. That means securing the greatest energy return from industrial society isn't simply and issue of maximising the energy return at the point of energy production, but at the point of delivery as "economic entropy" -- we have to overcome entropy, creating order, so that during the economic process can degrade that order through consumption and use and derive "value" from the economic process. That's the thermodynamics of the economic process.

As far as I'm concerned, any human process that can maintain it's energy balance above 15:1 is on its way out; it represents a dead weight to the economy and drags down the efficiency of everything else. E.g., in the days when American oil was a few dollars a barrel the energy return was 100:1; American production today is in the low 20s; Arctic and deepwater oil are likely to fall below 20 -- which is why, not coincidentally, you now find the major oil execs. talking about "the end of cheap oil".

An Inspector Calls wrote:
Quote:
Can you point me to any research that says the plastic matrix can be reused?


The original research paper (Kanno) talked of the adsorbant material being "robust". There are now papers pointing to the adsorbant being fixed as a continous belt suspended in an ocean current - and such systems recovering 6 tons per annum. And then there are (French) papers that propose using no adsorbant but instead nano-filtration. It takes no effort to find these papers using google and it's left as an exercise.


Certainly I would have thought that membrane separation would be more effective from the materials point of view, which is why I originally talked about pumping; but you still have to maintain sufficient pressure across the membrane to concentrate the ions (and, as I remember from looking a membranes as part of desalination, the membranes are highly susceptible to problems/damage from pollutants, especially dissolved oils and solvents).

An Inspector Calls wrote:
And just to go right back to the beginning of this discussion: the reason I made an example of seawater extraction was to highlight that as this was perhaps the lowest concentration of uranium we know about, and if we can extract that economically and thermodynamically efficiently, then when we consider other sources


The difficulty is that all those other sources are cemented into rock, and usually they're igneous or metamorphic rocks meaning that leaching doesn't produce a great return. Consequently you're always having to put large amount of mechanical energy into the process to grind the rocks to a fine powder so that leaching can work, but what absolutely drives the energy demand of mining is ore quality. A 1% ore will produce a tonne for every 100 tonnes of rock, at 0.1% its 1000 tonnes per tonne, but when we get down to 0.01% ores, we're talking 1 tonnes per 10,000 tonnes of rock -- all being shattered, scooped and then hauled out of a large hole in the ground to the processing plant. And at present about 30% to 50% of known uranium reserves are below 0.1%, and at present that's what the industry will have to start mining in order to keep supplies flowing in the 2020s -- with or without a nuclear renaissance.

Seawater is the complete opposite to hard rock working. All you have to overcome is the entropy of mixing because the uranium is already in solution, although that is still a significant amount of energy; and it's why -- unless we could raise the productivity of the process through the production of other essential metals -- land-won minerals will always be the better option, at least for the foreseeable future.

An Inspector Calls wrote:
So: nuclear power is not going to fail through any lack of fuel - probably ever.


Absolutely it will fail because it's return is already well below 20, and once the average ore quality approached 0.05%-0.01% it won't maintain a sufficient 'head' or 'energy potential' to be a viable source of energy. It's the same issue with biofuels -- they're a complete waste of space (literally!), and don't begin to address the carbon emissions issue, because you can't process them into petroleum substitutes and produce a significant enough energy return to make them self-supporting (which is why they have to be so heavily subsidised).

Have a look at this, it looks at similar issues -- http://www.theoildrum.com/story/2006/8/2/114144/2387

...and definitely look at some of the comparisons between conventional, nuclear and renewables in this article -- http://www.energybulletin.net/53475

A lot of "greenies" are anti-nuclear because they're pro-renewable; some greenies are pro-nuclear because they're anti-carbon; I'm "pro-reality", I assess all ideas on the basis of the physical laws that make the world tick -- and I don't care how cute, cuddly or iconic they are, if, on a time scale of say 200-300 years, they make no sense to the future viability of our species then I see no point in doing them when there are other options available.

And, in any case, we're going to run out (well, not "run out" precisely, but the supply and demand economics will mean that the technology is only viable for specialised or minority application across society) of indium for our computer chips, gallium for the fancy PV panels, and phosphate rock that keeps about 2.5 billion people alive due to the green revolution, BEFORE we'll "run out" of uranium.

That's the problem with the nuclear argument, and the carbon argument, like many others, is that they're one-dimensional (in the best Marcusian sense); people fixate on only a single dimension of the human system to the exclusion of the related processes that are equally knackered. It's only by developing systemically-oriented, synergistic solutions to the drivers of unsustainable human development that we've got any hope of reaching 2100 with more than 2 billion people left alive (see http://www.fraw.org.uk/f.html?csiro2008 -- if you're short of time just read the 'conclusions' section).
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mobbsey



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PostPosted: Thu Mar 24, 2011 9:23 am    Post subject: Reply with quote

Anyway, after our very enjoyable discussions...
did anyone actually listen to the Costing the Earth programme?
http://downloads.bbc.co.uk/podcasts/radio4/costearth/costearth_20110323-2125a.mp3 Rolling Eyes
or iPlayer,
http://www.bbc.co.uk/programmes/b00zphnr
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PostPosted: Thu Mar 24, 2011 11:54 am    Post subject: Reply with quote

I am under no illusions that an energy recovery rate close to 1 is good. I'm not particularly bothered about the result I get being quite low because it is founded on figures for the adsobent which neither of us can confirm - the weight used, its reusablity, and its energy content . You will also be surprised to find that workers in the field of metal extraction from seawater (and there are many) are fully aware of the energy balance and the economic balance. This is particularly good:
http://www.springerlink.com/content/y621101m3567jku1/fulltext.pdf
(Incidentally, therein a graph of adsorbent efficiency for repeated cycles - 6 are plotted, and ithe thermodynamics improve with each reuse).

I don't accept your dismissal of higher burn rate efficiencies than 5 % since it is known that concepts such as the FBR and CANDU have been successful in the past. There is no particular need to explore these technoligies at present because of an abundance of cheap uranium - the reason the Dounreay FBR was terminated. However, they could increase uranium resources by a factor of 50.
(Nuclear energy: principles, practices, and prospects by David Bodansky)

I don't accept your dismmissal of nuclear power plant thermal efficiency achieving 40 % since our own AGRs already have efficiencies of 41 %.

Apply these concepts and the extraction from seawater becomes a very attractive process.

Next we have:
Quote:
As far as I'm concerned, any human process that can maintain it's energy balance above 15:1 is on its way out; it represents a dead weight to the economy and drags down the efficiency of everything else.
and later
Quote:
Absolutely it will fail because it's [nuclear] return is already well below 20

Well, that's a problem because all those remarks apply equally well to wind power. We know that the energy payback period for an onshore wind turbine is about 2 years, and it will last 20 years (if it's very, very lucky). So it's energy payback is 10 times. Doomed according to you! Moreover it's doomed economically if it requires a subsidy (as well as capital grants) of £45/MWh. And offshore wind is even worse, both economically and thermodynamically. In that particular instance the grid losses (which you quote as 10 %, but are usually below 5 % apart for the most isolated locations) may well reach higher than 10 % because of their remoteness, and the use of DC lines with rectifier/inverter systems. Offshore wind needs a subsidy of £90/MWh!

And, falling back to economics as a reflection of the underlying thermodynamics (excluding the externalities of wind power for the moment), if wind is that bad, what about PV solar which has to be subsidised at £500/MWh!

The thermodynamics of industrial process: there are simply huge amounts of uranium, and thus energy, disolved in seawater. The Gulf Stream transports 10 million tons per annum, capable of generating 300,000 TWh. The difficulty is extracting this diffuse resource. All those arguments apply to every one of the renewable resources: they're too diffuse. The only two that pass muster are large scale hydro (run of river/elevated lakes) and tidal barrage; both of these are viable because they have the benfit of a natural resource concentration system. But the greenies will accept neither!

Fortunately, there are less diffuse fissile material deposits avaialble before we come to seawater, esp. of thorium, and once the uranium extraction price starts to rise we can reach for seawater extraction combined with bredding techniques.

(Shortage of other materials. Neodymion for wind turbine magnets comes to mind. But one thing at a time . . .)
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PostPosted: Thu Mar 24, 2011 12:00 pm    Post subject: Reply with quote

mobbsey wrote:
Anyway, after our very enjoyable discussions...
did anyone actually listen to the Costing the Earth programme?
http://downloads.bbc.co.uk/podcasts/radio4/costearth/costearth_20110323-2125a.mp3 Rolling Eyes
or iPlayer,
http://www.bbc.co.uk/programmes/b00zphnr

Yes I did - it was mostly about waste management (at both ends of the spectrum - mining pollution as well as RAD waste).
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PostPosted: Thu Mar 24, 2011 12:53 pm    Post subject: Reply with quote

An Inspector Calls wrote:
Well, that's a problem because all those remarks apply equally well to wind power. We know that the energy payback period for an onshore wind turbine is about 2 years, and it will last 20 years (if it's very, very lucky). So it's energy payback is 10 times. Doomed according to you!


You can't accuse me of inconsistency on that one -- if you look at one of my previous replies you'll find that I've represented groups against the development of large wind farms. In fact, I've been representing the shortcomings of wind as a "solutions" ever since I developed a touring presentation on the subject entitled, "If wind turbines are the answer what was the question?".

Trying to see the world "as it is", from a physical point of view rather than the anthropomorphism that passes for common reality, can be both a curse and a blessing: on the one hand, it simplifies understanding because you can dispense with the distortions and often illogical compromises of politicised debate; on the other hand consistently holding that view tends to make you rather unpopular. Personally I'm prepared to take the consequences of the latter because of the clarity the former gives to my work.

I do not accept "environmentalism" as a pre-defined philosophy; by questioning all aspects of it you give the ideas "life", but more importantly you're able to develop a more incisive critique of what really constitutes "the problem".


An Inspector Calls wrote:
Shortage of other materials. Neodymion for wind turbine magnets comes to mind. But one thing at a time


If you're interested in that aspect of the debate you might like to have a look at my latest work on that very subject (I also have a go at PV and other "green technologies" too, if that helps) --
http://www.fraw.org.uk/workshops/limits_to_technology/virtual_presentation.shtml
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An Inspector Calls
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PostPosted: Thu Mar 24, 2011 12:56 pm    Post subject: Reply with quote

Just an additional point. You point to me to this paper:

Quote:
...and definitely look at some of the comparisons between conventional, nuclear and renewables in this article -- http://www.energybulletin.net/53475


So many papers from the green camp start with good intentions but then slew their argument with data that gives them the conclusion they want to read. This is no exception, it seems to me.

Where on earth does he get his power plant lifespan data from? This is critical to all forms of energy production balancing if you are to swamp the energy capital expenditure.

So here we have green technologies with unheard of lifespans (in years):
    wave 20 (2 months might be more realistic)
    wind 21 (perhaps the odd turbine)
    tidal stream 20 (where?)
    tidal range 120 (yes, give him that, sense at last)


And then, surprise, fossil fuel technologies with conveniently short lifespans

    coal 31 (in days of yore perhaps, but not these days)
    coal with ccs 23 (why less? and where's the data from)
    gas 32 (don't be ridiculous - the one fossil error on the plus side - 20 if you're lucky)
    nuclear 29 (far too low - what a surprise)


Get the lifespan data wrong and you will distort both figures (EROEI and EIRR) used in the paper. That's especially true of a figure that bases itself on IRR - an economic assessment to be avoided.
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mobbsey



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PostPosted: Thu Mar 24, 2011 12:58 pm    Post subject: Reply with quote

Bandidoz wrote:
Yes I did - it was mostly about waste managemen


Yes, I think their trail for the programme was a little misleading. No consideration of resources, and whilst it referenced the health effects of mining it neglected to look in more detail at the rest of the fuel cycle.
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