We cannot drill our way out of this oil crisis. Since 2000, oil companies working in the U.S. have doubled the number of wells drilled per year.
Although increased drilling has added new oil to the nation's supply, it has not done so fast enough to offset the terminal decline of existing fields.
We are going to have to import more of our oil. Period.
Joined: Apr 28, 2005 Posts: 3277 Location: West shore Lake Eire, MI, USA
Posted: Mon May 14, 2007 7:02 pm Post subject: Re: Once-through total-use nuclear cycle possible?
Joe0Bloggs wrote:
So, breeders convert more fertile material into fuel than the fuel it consumes, but the reprocessing is expensive. Why is it that the fuel has to be taken out for reprocessing at all?
Mainly two reasons. Firstly at the enrichment concentrations allowed for civilian fuel the rods accumulate enough fission fragment waste over time that the breeding ratio falls below 1:1 and technically at that point they are high burn up converters, not breeders. Secondly if you use the fuel systems as currently used they can only maintain their physical integrity for a few years, as the Uranium/Plutonium/Actinides fission the fragments continue to build up. These chemicals are less dense than the heavy metals they derive from and hence require more space for the same weight of material. Once you have reached a certain pressure the fuel rods start to streatch, warp, or even crack open from internal pressure and gasseous or volitile fission fragments then escape into the primary coolant.
Quote:
Why can't the newly produced fuel be used directly?
Well actually quite a bit of it is used directly, however when the fission fragments accumulate they are like ashes on a fire, they tend to smother out the reaction by absorbing neutrons.
Quote:
Is it possible to design a reactor where fuel rods only have to be put in and taken out once--where the reactor continuously produces fuel from the fertile material and uses it up, until all the fertile material has been converted and all the fuel used up--and the spent fuel rod would be worthless and can be taken directly to disposal without reprocessing?
The short answer is no, provisionally. Instead of using solid fuel rods you can use molten salt as a fuel carrier and constantly seperate out the fission fragments while the reactor keeps running 24/7 except for maintenence periods. A Molton Salt reactor consumes actinide metals and produces heat and fission fragments and is so efficient in its neutron economy it can operate as a breeder with Thorium/Uranium/Plutonium/Actinide in a constantly adjusted ballance. If reactivity starts to fall the operators can just add fuel directly to the fuel flow channels brininging the reactivity back up. If you want more details simply google MSBR and MOSEL (Molten Salt Breeder Reactor and Molten Salt Epithermal Reactor). _________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
As a senior energy adviser in the Clinton administration, I recall attending a briefing by the National Academy of Sciences in 1996 on the feasibility of recycling nuclear fuel. I'd been intrigued by the idea because of its promise to reduce the amount of waste that had to be buried, where it could conceivably seep into drinking water at some point in its multimillion-year-long half-lives.
But then came the Academy's unequivocal conclusion: the idea was supremely impractical. It would cost up to $500 billion in 1996 dollars and take 150 years to accomplish the transmutation of dangerous long-lived radioactive toxins.
...
We are better off by investing in renewable energy and conservation, rather than pouring billions of dollars into the same old limitless energy schemes of our nuclear laboratories.
_________________ "Once the game is over, the king and the pawn go back in the same box."
-Italian Proverb
As a senior energy adviser in the Clinton administration, I recall attending a briefing by the National Academy of Sciences in 1996 on the feasibility of recycling nuclear fuel. I'd been intrigued by the idea because of its promise to reduce the amount of waste that had to be buried, where it could conceivably seep into drinking water at some point in its multimillion-year-long half-lives.
But then came the Academy's unequivocal conclusion: the idea was supremely impractical. It would cost up to $500 billion in 1996 dollars and take 150 years to accomplish the transmutation of dangerous long-lived radioactive toxins.
...
We are better off by investing in renewable energy and conservation, rather than pouring billions of dollars into the same old limitless energy schemes of our nuclear laboratories.
What does a pollitically motivated anti nuclear rant have to do with reallity? Very little, it gives no facts that can be checked, no figures that can be tested. Just generalities and speculation.
I have respect for http://www.wise-uranium.org/ and related websites because they give you their assumptions and let you test them. I don't agree with some of their conclusions, but I beleive they are sincere.
The pollitical hack you cited above, not so much. _________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
Posted: Mon May 28, 2007 3:11 pm Post subject: Re: Fission FAQ v 1.5
Tanada wrote:
What does a pollitically motivated anti nuclear rant have to do with reallity? Very little, it gives no facts that can be checked, no figures that can be tested. Just generalities and speculation.
As opposed to your Pro Nuclear agenda
Quote:
It would cost up to $500 billion in 1996 dollars and take 150 years to accomplish the transmutation of dangerous long-lived radioactive toxins.
Theres one you could check there are more...
The "reality" is that politics will determine how many nuclear plants are built. Just like many other activities human beings engage in.
So you can pretend that politics does not exist and nuclear is going to provide cheap abundant energy for all based on the numbers. Or in fact you can take a look at reality you know the real world and realize that nuclear and politics plays a major role. _________________ "Once the game is over, the king and the pawn go back in the same box."
-Italian Proverb
Joined: Apr 28, 2005 Posts: 3277 Location: West shore Lake Eire, MI, USA
Posted: Mon May 28, 2007 8:55 pm Post subject: Re: Fission FAQ v 1.5
Concerned wrote:
Quote:
It would cost up to $500 billion in 1996 dollars and take 150 years to accomplish the transmutation of dangerous long-lived radioactive toxins.
Theres one you could check there are more...
The "reality" is that politics will determine how many nuclear plants are built. Just like many other activities human beings engage in.
So you can pretend that politics does not exist and nuclear is going to provide cheap abundant energy for all based on the numbers. Or in fact you can take a look at reality you know the real world and realize that nuclear and politics plays a major role.
Numbers without context are meaningless. What if you spend a trillion dollars does that make the solution occur in 75 years? Or is money additive to the suppossed solution and with a Trillion dollars everything is sweetness and light in 15 years? Or is 500 Billion the optimum spending rate and 150 years the optimum timetable? What is the rationale for the numbers presented? That is the pollitics that matters, numbers without the context are just numbers that might or might not mean anything.
Physical laws do not bend to pollitics, that is what PO is all about. If you don't understand that I feel very sorry for you. _________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
Posted: Tue May 29, 2007 5:36 am Post subject: Re: Fission FAQ v 1.5
Tanada wrote:
Physical laws do not bend to pollitics, that is what PO is all about. If you don't understand that I feel very sorry for you.
Sure they do.
Say there is a "physical law" that says if you do the calculations right there is enough energy in the uranium of the earths crust and oceans to supply 9billion people with double the energy the USA consumes today for the next 20,000 years.
BUT if the politics don't allow the construction of nuclear facilities then that "physical rule or law" will never be realized.
It will remain hypothetical, which is exactly what much of the discussion on nuclear energy is about. How it can hypothetically solve our energy conundrum.
Or say that it takes more effort to safely dispose of nuclear waste than what can usefully be produced with the energy generated (political/economic decisions) then nuclear is a non starter.
Or say that a country like ummm... France decides to heavily subsidize their nuclear electrical generation capacity (political)...
A physical law is nothing but that. How it is used and implemented comes down to political and economic decisions.
How is the nuclear barrow coming along by the way? Are they still building more coal/gas fired plants around the globe than nuclear? _________________ "Once the game is over, the king and the pawn go back in the same box."
-Italian Proverb
Posted: Tue May 29, 2007 5:54 am Post subject: Re: Fission FAQ v 1.5
Concerned wrote:
Tanada wrote:
Physical laws do not bend to pollitics, that is what PO is all about. If you don't understand that I feel very sorry for you.
Sure they do.
Say there is a "physical law" that says if you do the calculations right there is enough energy in the uranium of the earths crust and oceans to supply 9billion people with double the energy the USA consumes today for the next 20,000 years.
BUT if the politics don't allow the construction of nuclear facilities then that "physical rule or law" will never be realized.
It will remain hypothetical, which is exactly what much of the discussion on nuclear energy is about. How it can hypothetically solve our energy conundrum.
At some point, when energetic disaster became obvious all NIMBY considerations will go to bin basket and hundreds of nuke plants will be build in haste and according to shabby standards.
Physical laws are likely to put limits on that in another fashion.
Rates of production of fuel, enrichment of it and rates of dealing with waste or rates of production of some critical materials for reactor construction, production of critical spares etc will not allow to run more then so or so reactors concurrently worldwide.
And the maximum number of concurrently operating reactors may be dissapointingly low at "saturation point".
Quote:
Or say that a country like ummm... France decides to heavily subsidize their nuclear electrical generation capacity (political)...
It is really useless to claim that subsidies are making nukes not attractive.
Once electricity price go up (inevitable), you will no longer need those.
Posted: Thu May 31, 2007 2:03 pm Post subject: Re: Fission FAQ v 1.5
EnergyUnlimited wrote:
It is really useless to claim that subsidies are making nukes not attractive.
Once electricity price go up (inevitable), you will no longer need those.
Except it looks like Solar will have it all over nuclear price wise. _________________ "Once the game is over, the king and the pawn go back in the same box."
-Italian Proverb
Posted: Fri Jun 01, 2007 2:00 am Post subject: Re: Fission FAQ v 1.5
Concerned wrote:
EnergyUnlimited wrote:
It is really useless to claim that subsidies are making nukes not attractive.
Once electricity price go up (inevitable), you will no longer need those.
Except it looks like Solar will have it all over nuclear price wise.
Solar does not work overnight and wind blow at random.
I agree, that you may get solar or wind cheaper than nuclear, but such energy will not always be available.
Nuclear is about the only serious energy source other than FF and hydro, capable to provide baseload supply.
NB. I have great doubts about storing solar heat in form of molten salts, nitrates alike. We could easily run into white elephant project here...lakes of molten nitrates...
No serious installation using it is working now.
And what, if cloudy day follows frosty night?
What about polar regions, or even non-tropical/subtropical regions?
Posted: Fri Jun 01, 2007 5:04 am Post subject: Re: Fission FAQ v 1.5
EnergyUnlimited wrote:
NB. I have great doubts about storing solar heat in form of molten salts, nitrates alike. We could easily run into white elephant project here...lakes of molten nitrates...
No serious installation using it is working now.
The latest big Spanish solar installations are using molten salts, I think. So it can't work that badly.
I agree that solar isn't all the answer, though. My suggestion for the electricity mix of any country would be:
- As much hydro as possible
- Solar, wind and geothermal in the locations where it works well, and as much as possible in those locations
- Complete electricity needs with nuclear, until we find something better... or uranium runs out and we are forced to find something better or do without
- Phase out fossil fuels as quickly as possible
Posted: Sat Jun 09, 2007 2:50 am Post subject: Re: Fission FAQ v 1.5
Nuclear Future?
Dream on nuke advocates...
Quote:
He told his audience that fuel is four to five times the ‘hyped’ cost of nuclear power – between 20 and 25 percent instead of the mere five percent.
Dr. Kim shot down the premature conclusion that utilities would rather pay the high prices instead of going through a costly decommissioning process. He said, “There is no compulsion to immediately decommission – stations can be held in standby or cold shutdown.”
Finally, he took up the matter of ‘utilities not caring about fuel costs.’ He pointed out, “Take $900 million from your company’s annual net profits. See how happy your management is.”
Read this and weep nuke saviours _________________ "Once the game is over, the king and the pawn go back in the same box."
-Italian Proverb
Posted: Sat Jun 09, 2007 3:21 am Post subject: Re: Fission FAQ v 1.5
Concerned wrote:
Nuclear Future?
Dream on nuke advocates...
Quote:
He told his audience that fuel is four to five times the ‘hyped’ cost of nuclear power – between 20 and 25 percent instead of the mere five percent.
Dr. Kim shot down the premature conclusion that utilities would rather pay the high prices instead of going through a costly decommissioning process. He said, “There is no compulsion to immediately decommission – stations can be held in standby or cold shutdown.”
Finally, he took up the matter of ‘utilities not caring about fuel costs.’ He pointed out, “Take $900 million from your company’s annual net profits. See how happy your management is.”
If there is any long term future of nuclear, it will either be based on thorium cycle or FBR.
Thorium cycle is better bet, as it was demonstrated to work in civilian set up and certain type of reactor already in use can work with it. On the other hand civilian FBR are failures up to date.
There is also 200 times more thorium around, than U235.
Posted: Mon Mar 17, 2008 12:14 pm Post subject: Re: Fission FAQ v 1.5
Quote:
Is it possible to design a reactor where fuel rods only have to be put in and taken out once--where the reactor continuously produces fuel from the fertile material and uses it up, until all the fertile material has been converted and all the fuel used up--and the spent fuel rod would be worthless and can be taken directly to disposal without reprocessing?
They don't use up all of the potential energy in the fuel, but pebble bed reactors do operate continuously as the pebbles cycle down to the bottom, and are just topped up. They are also modular which should reduce construction costs and interest.
http://en.wikipedia.org/wiki/Pebble_bed_reactor
CANDU reactors do not need to stop for refuelling either.
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