16Feb/1013
Tom McCabe on Nuclear Fusion
Tom McCabe at the Rational Futurist has a new article up; "The Real Story Behind Fusion Energy". I suggest you check it out -- it dispels a great many myths that we have been told about fusion power, and recommends the construction of thorium-powered fission reactors instead.
February 16th, 2010 - 19:47
Pretty solid stuff. Unfortunately for McCabe, the problems he lists apply to fission as well. It’s a strong argument against nuclear power in general.
February 16th, 2010 - 22:14
the arguments are against certain tokomak configurations. However, even so-so fusion involving tokomaks or laser fusion that did not have great prices would enable nuclear fission to have no nuclear waste (complete burn of actinides) and could enable the use of depleted uranium for fuel.
The dense plasma focus and iec fusion can enable lower cost and direct conversion to electricity without using turbines. Using turbines is not necessarily a bad thing and there are more efficient versions. Supercritical CO2 turbines are a lot smaller.
February 16th, 2010 - 22:36
I would summarise the article this way:
(1) the fusion “propaganda” (which has not “saturated the airwaves” by the way) is misleading because it avoids talking about all the problems that could make fusion much more expensive, possibly less so than fission.
(2) if a thorium plant and a fusion plant were equal with respect to fuel availability, safety, first-generation pollution debt, the the thorium solution is superior because the research is already done, and no more billions would have to be spent.
True as stated, but those “billions on research” might be messing with your sense of scale.
ITER projected cost: ~15 billion AUD
Cost of replacing 2010 global electricity generation with fission power: ~15 trillion AUD (at ~1 AUD per watt)
February 16th, 2010 - 22:39
Ah the end of that first point should have said “possibly more so” rather than “possibly less so”
February 17th, 2010 - 05:20
A “fusion sucks” article. That is a silly sentiment, IMO.
February 17th, 2010 - 08:14
“However, even so-so fusion involving tokomaks or laser fusion that did not have great prices would enable nuclear fission to have no nuclear waste (complete burn of actinides) and could enable the use of depleted uranium for fuel.”
Interesting… how would that work? Are you just using the fusion reactor as a neutron source? If so, you can use an existing fission reactor (see: CANDU, thorium plants).
“Cost of replacing 2010 global electricity generation with fission power: ~15 trillion AUD (at ~1 AUD per watt)”
You forgot the decimal point, it’s $1.5T (250 W per person * 6B people * $1/watt).
“ITER projected cost: ~15 billion AUD”
Plus every other tokamak fusion project, of which there have been dozens, times one over the probability that fusion will eventually be cost-competitive with fission (because if it isn’t, the money all goes down the tubes).
February 17th, 2010 - 10:04
Tim, this is not a typical “fusion sucks” article. Tom McCabe understands the issues with significant depth. You have a powerful habit of quickly putting things into preestablished categories to dispel cognitive dissonance.
I am not completely in agreement with Tom in his article, but at least I’m subtle enough to let all the shades of grey show through in my personal interpretation, which I’m not always interested in posting because it takes time.
February 17th, 2010 - 10:32
Yes, the fusion reactor would be a neutron source. Yes, certain advanced fission reactor designs could be used as well for transmutation. Which system is best depends upon design and execution.
There are several Fusion – fission hybrid proposals
http://www.utexas.edu/news/2009/01/27/nuclear_hybrid/
One hybrid would be needed to destroy the waste produced by 10 to 15 LWRs. The process would ultimately reduce the transuranic waste from the original fission reactors by up to 99 percent. Burning that waste also produces energy.
Livermore has the Laser Inertial Fusion Engine concept
Neutronics Design of a Thorium-Fueled Fission Blanket for LIFE …
Helion energy (trying to make field reversed fusion) proposes a neutron source transmutation system
http://nextbigfuture.com/2009/12/development-path-for-helion-energy-for.html
It seems likely that using the early nuclear fusion systems to help resolve nuclear waste issues from fission is a win-win and some of the early fusion systems could be a lot cheaper and faster to develop than the advanced fission reactors.
I do like the liquid flouride thorium reactor. It does seem to have at least ten years for a development path. The Japanese Fuji molten salt designs seems to be the way to go with that. China, India or Russia would be the places for lowest cost and fastest development. The Russians seem to prefer various kinds of fast breeders though.
Getting all the way to complete deep burn on the fission reactor might not happen in as timely or economic fashion and there will be 600-1000+ LWR that will be running for another 40-80 years. So 60-100 neutron transmuters of some kind seem to be needed. The economics would not have to beat the fission or other energy sources the economics would need to beat reprocessing or accelerator driven transmutation. 20 billion for each reprocessing facilities in France and Japan to make MOX fuel. So even having double the cost for a fusion transmuter that also generates some power would beat the reprocessing or waste storage system costs.
February 17th, 2010 - 10:33
McCabe is clearly correct with regards to the Tokamak and laser fusion efforts. These programs are essentially welfare for PhD’s and have no chance of success. I think the laser fusion scheme is really a cover for weapons research, but that’s another story.
McCabe is also correct that there are many new fission concept such as the Thorium-based MSR and LFTR, as well as travelling-wave reactors that are far more promising, and being developed by various governmental and commercial parties.
However, where I think McCabe is wrong is that there are alternative fusion concepts being developed privately (Tri-Alpha’s FRC, Helion Power’s FRC, General Fusion) or being funded at small levels by the military (IEC polywell). I think one or more of these concepts have a chance of working out.
There is the polywell discussion group at:
http://www.talk-polywell.org/bb/index.php
February 17th, 2010 - 11:55
I feel compelled to bring Charles G. Beaudette’s Excess Heat into this discussion. (Blame Ben Goertzel.) It’s a fascinating look at the fusion research industry. I wonder where we’d be today if low energy nuclear reactions had gotten some of that funding.
February 17th, 2010 - 12:45
“However, most of the effort doesn’t go into basic research; it goes into simply making the thing big enough to generate more power than it consumes.”
Yes, that’s the entire point of fusion research: to surpass the breakeven point where you get more energy out than you put in. Incredible things happen when you pass a breakeven point. Rockets that pass the breakeven point of escape velocity can travel past Neptune; those that don’t, fall to the ground. Manufacturing systems (or biological systems) that can achieve the breakeven point of making all of their components can self replicate. The power of an AI that can achieve the breakeven point of reprogramming itself has been discussed extensively by Tom and Michael.
Sometimes slow, boring, incremental steps lead to breakeven points that have dramatic consequences.
I agree with Tom that there won’t be a “fusion singularity” which rapidly solves the world’s energy problems, because of the reasons that Tom described. Fusion will lead to dramatic, but not fantastical, changes. The same may be true of many other technologies.
Tom wrote a very good article. I agree with Tom about the value of thorium fission and with Brian Wang about the value of Bussard polywell fusion.
February 17th, 2010 - 14:12
Interesting and timely writing – I read the Wired article about Thorium reactors a couple months ago and have been following this closely ever since. The perspectives on fusion are helpful.
By all accounts Thorium reactors are both cheap to build and relatively easy to fuel and operate. Of course when you state costs in terms of immediately replacing an existing system with a new system the numbers are going to be daunting, just like the cost of building the current internet infrastructure from scratch would carry a daunting price tag. But the key is we don’t have to do that.
Until there is a “Thorium Lobby” in DC, though, that is likely not going to happen.
February 21st, 2010 - 03:02
There is another alternative fusion concept, the aneutronic reactor was designed to generate electricity directly without neutrons. I think this machine is well-conceived, because it was developed as an improvement of previous fusion devices.