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Author Topic: In response to the nuclear fusion interview today  (Read 3590 times)

Offline MarkPawelek

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decades away! I think she really meant centuries away, if never.
  • Fusion may not work because the assumptions behind it are wrong! Plasma atoms may quickly become uncharged hence no longer contained.[1]
  • Nuclear fission is also carbon free energy. Transatomic power calculate the cost of energy from their WAMSR design at 6¢/kWh[2]
  • The kinds of 'waste' one gets in nuclear fission are not nearly as dangerous as scientists tell us. Low dose radiation is 3 to 4 orders of magnitude less harmful than Linear No-threshold (LNT) models predict. The LNT model regulatory agencies use is a fraud, which has been accepted for 58 years.[3,4]
  • Renewables are a joke. EROI studies indicate that a minimal EROI factor of 12 is required[5] to sustain industrial civilization[6]. Renewables can't get near that value when energy storage is factored in[7] and without energy storage renewables are carbon intensive (needing gas- or coal- fired generation to make them work without blackouts]

Thanks for answering my tweet. I'm unconvinced by the answer. This is why:
  • Why do BBC science shows give so much publicity and time to nuclear fusion and no time to Gen IV fission?
  • Has there been a single TV/radio show explaining why Gen IV breeder reactors are so much more likely to provide for our energy needs than pie-in-the-sky fusion?
  • Why does the EU fund fusion to the tune of €1 billion / year yet give practically nothing to Gen IV fission research?
I think fusion is politics not science.

Refs:
PS: I'm not against fusion.
« Last Edit: 31/08/2014 19:24:10 by MarkPawelek »


 

Offline MarkPawelek

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What to Do with a Failed $5 Billion Experiment?
« Reply #1 on: 31/08/2014 20:36:51 »
Quote
So you spent 17 years and $5 billion to build a fusion experiment. You built a facility wider than the length of three football fields. You built a 400-foot-long laser with more than 33,000 optical parts; it is currently the highest energy laser in the world. You've been through more budget overruns and management problems than you'd care to admit.

Now, you finally turn the thing on at full power and carry out your experiment. And it fails monumentally. Now what?

This is the dilemma facing the National Ignition Facility (NIF). Built with the promise of providing ignition -- creating fusion energy greater than the energy needed to release it -- NIF fell 28,000 times short of its goal. No one knows how to fix it. So NIF has now been finding other things to occupy its time.
- What to Do with a Failed $5 Billion Experiment? [nofollow]
 

Offline alancalverd

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Re: In response to the nuclear fusion interview today
« Reply #2 on: 01/09/2014 00:07:36 »
In 1955 the Zeta reactor was announced, along with the statement that unlimited fusion power was 5 years away. Over the past 50 years that figure has gradually increased to 25 years. Several good friends have built careers and retired on handsome pensions thanks to fusion reactor projects. It's an intriguing problem but I wouldn't bet on it becoming a serious power source before the whole economy inverts and we don't need it.   
 

Offline PmbPhy

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Re: In response to the nuclear fusion interview today
« Reply #3 on: 01/09/2014 00:18:44 »
There are many reasons to use fusion over fusion such as the waste from fission is dangerous and it takes a lot of money and security to store it. It can readily be used as a dirty bomb too. On the other hand fusion uses deuterium as a fuel and the waste products in fusion power is much safer. The half-life of the radioisotopes produced by fusion tends to be less than those from fission, so that the inventory decreases more rapidly. See http://en.wikipedia.org/wiki/Fusion_power#Waste_management

It's impossible for a fusion reactor to have a melt down too. As that link say There is no possibility of a catastrophic accident in a fusion reactor resulting in major release of radioactivity to the environment or injury to non-staff, unlike modern fission reactors.
 

Offline MarkPawelek

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Re: In response to the nuclear fusion interview today
« Reply #4 on: 01/09/2014 07:38:28 »
to: PmbPhy

None of your points are unanswerable:

  • waste from fission is dangerous
    answer: Low level waste is not nearly as dangerous as I've been led to believe. Risk is exaggerated 1000 to 10000 times. I was taught LNT in physics class as if it were gospel (and taught no alternative). There's no evidence for radiation harm at low levels : LNT is unfounded. (listen to this long interview [nofollow] with Dr Ed. Calabrese)
  • catastrophic accidents ... resulting in major release of radioactivity to the environment
    answer: stop building pressurised fission reactors. Alternative, non-pressurised, molten salt reactors (MSR [nofollow]) have no danger of such release under any reasonable scenario (and any possible release is, by nature, contained locally).
  • melt-down
    answer: By definition, there's no danger of a MSR melt-down.
  • half-lifes of radioisotopes produced by fission
    answer: build only reactors leaving no long-lived radionuclides (e.g. IFR [nofollow], WAMSR [nofollow], ...). Reactors should be designed to burn up radionuclides with long half-lives (actinides) leaving only fission products (having half-lives no more than 30 years : Cs-137 and Sr-90).  Such spent fuel will be safe from radioactivity after 300 years
« Last Edit: 01/09/2014 07:50:14 by MarkPawelek »
 

Offline alancalverd

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Re: In response to the nuclear fusion interview today
« Reply #5 on: 01/09/2014 08:11:33 »
Spent fuel isn't much of a scientific problem as it is concentrated and concentrateable: it's just a political problem of where to dump it. The difficult stuff is the vast amount of low-level activated and contaminated junk from decommissioned reactors. Alas, fusion reactors also produce neutrons and hence radioactive junk.

We know LNT is mere convenience but we are gradually discovering that the RBE of alpha radiation is a lot more than the ICRP consensus value. I think (hope) we will see a significant change in the basis of radiation protection legislation in the next 20 years or so.     
 

Offline JohnDuffield

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Re: In response to the nuclear fusion interview today
« Reply #6 on: 01/09/2014 11:50:41 »
Pete: take a look a Kirk Thorensen talking about thorium here.
 

Offline PmbPhy

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Re: In response to the nuclear fusion interview today
« Reply #7 on: 01/09/2014 13:48:50 »
Quote from: alancalverd
Spent fuel isn't much of a scientific problem as it is concentrated and concentrateable:
That's not what they do with it though. See
http://www.nei.org/Issues-Policy/Nuclear-Waste-Management
Quote
Most used fuel from nuclear power plants is stored in steel-lined concrete pools filled with water, or in airtight steel or concrete-and-steel containers.

What I don't get is why not fusion other than the notion "it works, don't fix it" which in this case I don't think that motto applies. All the problems with storage are nowhere as severe as they are with fusion waste. The products of fusion is helium as you know. Fill children's balloons with it, as they say. :)

http://www.nei.org/Issues-Policy/Nuclear-Waste-Management/Used-Nuclear-Fuel-Storage
Quote
Used nuclear fuel is in storage at the nation’s nuclear energy facilities. Most plants store used fuel in steel-lined, concrete pools filled with water, which acts as a natural barrier for radiation. The water also keeps the fuel cool while radiation decays. The water itself does not leave the used fuel pool.
« Last Edit: 01/09/2014 13:56:53 by PmbPhy »
 

Offline evan_au

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Re: In response to the nuclear fusion interview today
« Reply #8 on: 01/09/2014 18:11:03 »
Quote
The water itself does not leave the used fuel pool.

The author left off the implicit "...we hope!".
 

Offline alancalverd

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Re: In response to the nuclear fusion interview today
« Reply #9 on: 02/09/2014 12:03:58 »
Quote from: alancalverd
Spent fuel isn't much of a scientific problem as it is concentrated and concentrateable:
That's not what they do with it though. See
http://www.nei.org/Issues-Policy/Nuclear-Waste-Management
It may be an engineering, economic or political problem, but not a scientific one.

Quote
What I don't get is why not fusion other than the notion "it works, don't fix it" which in this case I don't think that motto applies. All the problems with storage are nowhere as severe as they are with fusion waste. The products of fusion is helium as you know. Fill children's balloons with it, as they say.

Two problems (a) fusion doesn't work (yet, but that "yet" has been going on for 50 years and is likely to do so for another 50)  and (b) helium isn't the only product. There's a lot of neutron- and gamma-activated material outside the plasma ring.

 

Offline chiralSPO

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Re: In response to the nuclear fusion interview today
« Reply #10 on: 02/09/2014 14:45:53 »
I am a proponent of using fission power, so long as it can be done efficiently and safely. We do have to be careful about radioactive waste, but I think many people have an unreasonable phobia about this without realizing how much radioactive (and otherwise hazardous) waste is released by burning coal.

I would like to point out, however, that we already have a massive, self-sustaining fusion power plant a few million miles away--we just have to tap in to it!
 

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Re: In response to the nuclear fusion interview today
« Reply #10 on: 02/09/2014 14:45:53 »

 

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