I fully expect angry comments about this....
Here's how a cold fusion experiment is supposed to work, broadly. One takes an electrochemical cell containing either regular water or D2O, and as one electrode uses palladium (prepared in some meticulous way, to be discussed further below). Then one sets the electrochemical conditions such that hydrogen (or deuterium) ions are electrochemically favored to go into the palladium lattice, up to some very high loading. It's been known for decades that Pd likes to take up hydrogen, so the fact that one can do this is of no surprise. Now, while all this is going on, one carefully monitors the temperatures of the electrodes, the water, etc. The experimental claim, coarsely described, is that after some time, cells containing heavy water under these conditions begin to get hot (but not cells containing ordinary water!). Ideally one does good calorimetry and can measure the amount of energy that comes out of the cell in the form of heat, vs. the amount of energy put in in the form of integrated electrochemical current times voltage. The claim is that in some such experiments, the inferred amount of energy out is much larger than the electrical energy in. This is "excess heat".
So, what's the problem? Well, there are several issues.
1) Calorimetry can be a tricky business. This was the main criticism of the original Pons and Fleischmann work. From what I can tell, people have been much more careful about this than twenty years ago.
2) The experiments just aren't reproducible, in many senses of the term. For example, the temperature-vs-time evolutions of nominally identical cells are completely different, and all over the map. There are big fluctuations on many timescales all over the place. Sometimes the thermal output is big, sometimes it's small. This is generally swept aside by those doing the experiments, who take a wildly fluctuating response, integrate it, and claim reproducibility because the net integral ends up having the desired sign. Not the desired magnitude, just the desired sign. What would I expect to see in a well-controlled experiment? Take one large piece of palladium, cut it into thirds, and set up three identical cells. The temperature-time histories of these things should really reproduce. If you can't do that, then you don't have a controlled experiment. This isn't a small thing.
3) The cells stop working after a while. Unsurprisingly the time period varies from cell to cell. Now, why should this happen unless the underlying process is chemical in some way? By the way, some cells (but not all) "revive" when the electrochemical conditions are changed. Again, all of this is massively variable, even between nominally identical cells in the same labs.
4) The claim of excess heat assumes that there's no chemistry taking place. For example, what if I made that assumption and looked at my car engine? The amount of electrical power input by each spark plug is miniscule compared to the total power out. If I neglected chemical reactions, I'd come to the conclusion that something amazing was going on. Furthermore, if I normalized the output power by, say, the number of platinum atoms at the tips of the spark plugs, I might then conclude that the only way of achieving such power out was something like nuclear. That's the hazard of ignoring possible chemical channels. The issue here is that palladium is known to be highly catalytic, and there are certainly diffusion processes within solids that can be strongly influenced by isotopic differences. Moreover, the claim is also that surface prep of the Pd is of absolutely critical importance. Again, this sounds to me like catalysis, not a bulk effect. Now, you'd think this could all be resolved by analytical chemistry - look at the cell materials before and after running. Look at the water before and after running. However, remember that the different folks doing this disagree on basic analytical chemistry issues like the possible production of helium, tritium, etc. That has to make you wonder about how trustworty their collective analyses are.
Now, I'm not saying that there's nothing worth examining here. The DOD clearly thinks its worth looking into, and it would be nice to get this straightened out once and for all. However, 60 Minutes notwithstanding, the work is just not reproducible in the sense that most experimental physicists would use.
As a chemist, I'd say the work isn't reproducible either.
ReplyDeleteNicely put, Doug. To me it is also clear that chemistry plays a big role in this stuff. But that doesn't by itself mean that there is not also a role for nuclear reactions.
ReplyDeleteI don't have the feeling that the enthusiasts are pooh-poohing the irreproducibility, or the need to correct it if this is going to be accepted as real science. What troubles me more is that although they admit they don't know what's going on, they are happy to project cars that run for years on a single chemical charge, no radioactive biproducts, etc., etc.
For those who want to hear it from the enthusiasts, the ACS posted video from a news conference a month ago at their meeting in Utah (!), which is annotated a little at Advanced Nano.
You wrote:
ReplyDelete"For example, the temperature-vs-time evolutions of nominally identical cells are completely different, and all over the map."
That is completely incorrect. The control factors are well understood and they show up clearly in the data. I suggest you have a look at the graph on the first page here:
http://lenr-canr.orgYou will find 4,000 pages of similar graphs & data on this web site. I strongly recommend you review the scientific literature before making assertions about it.
Also, you wrote:
ReplyDelete"The claim of excess heat assumes that there's no chemistry taking place."
No one makes any such assumption. They have looked very carefully for chemical reactions. They have found none. Furthermore, cold fusion cells that do not have a single gram of chemical fuel in them have produced 100 to 300 MJ of energy, without producing a trace of chemical ash. Chemical sources of energy are conclusively ruled out.
Also, chemical reactions cannot produce tritium, x-rays, neutrons, transmutations and the other nuclear effect observed in these experiments.
Please do not imagine that people assume this or failed to do that. Thousands of papers on cold fusion have been published. They are available at any university library. Hundreds are available at LENR-CANR.ord. Read the literature -- don't jump to conclusions or make statements about experiments you have not read about.
An atom of carbon burning to carbon dioxide gives 4.078 eV. Fusing a pair of deuterium atoms gives more than 3 MeV. If we accept 60 Minutes at face value, "cold fusion" operates a million times crappier than mere combustion.
ReplyDeleteIf "cold fusion" worked a million times better it would still be crap. How much energy is required concentrate deuterium from 0.015%% natural abundance to 99%? You don't make profit until you've paid your debts.
Jed - I have looked at papers. Indeed, I looked at exactly the stuff that 60 Minutes was shopping around trying to find an appropriate person to go review the experiments at the labs.
ReplyDeletePerhaps I could have worded my comments more carefully. The description of the heat as "excess" assumes that the only input is the electrochemical current+voltage. Is that better?
Regarding the analytical chemistry, there are multiple groups working on this stuff that disagree amongst themselves about whether there is tritium, helium, neutrons, etc. My point is, if different groups disagree about whether there is tritium in the effluent, then how much weight should I put on the statement that there is definitely no chance of chemistry going on.
I wish the enthusiasts the best of luck. If this turned out to be a nuclear process, it would be incredibly exciting. I just think that my threshold for such a claim is really high. It would require us to throw out just about everything we know about nuclear fusion (which is quite a bit).
organiker@lycos.com
ReplyDelete"An atom of carbon burning to carbon dioxide gives 4.078 eV. Fusing a pair of deuterium atoms gives more than 3 MeV. If we accept 60 Minutes at face value, "cold fusion" operates a million times crappier than mere combustion."
This comment makes no sense. There was no mention of the energy output in this program. Cold fusion cells have produced 10,000 times more energy than an equivalent mass of chemical fuel could, and there is every reason to believe they can produce millions of times more. Cold fusion cells have achieved temperature and power density comparable to a fission reactor core.
"If 'cold fusion' worked a million times better it would still be crap."
It does work a million times better than combustion.
"How much energy is required concentrate deuterium from 0.015%% natural abundance to 99%? You don't make profit until you've paid your debts."
Heavy water costs $500 to $1000/kg retail depending on purity. It is much cheaper in industrial quantities. Most of this cost goes to pay for the energy required to separate the heavy water from ordinary water. 1 kg of heavy water in cold fusion produces 69 million MJ of heat, the equivalent of 523,000 gallons of gasoline. Using present day extraction techniques, 0.015% of the heavy water would be needed for separation. Compare this to the 10% of oil needed to extract and refine oil. The overhead is much lower.
Advanced methods of separation have been developed that would require much less energy and produce less pollution.
You need to read the literature on this subject before commenting on it.
You wrote:
ReplyDelete"Indeed, I looked at exactly the stuff that 60 Minutes was shopping around trying to find an appropriate person to go review the experiments at the labs."
What do you think of the person they found, Prof. Duncan? Do you agree with the APS that he is qualified to evaluate the experiments?
"Perhaps I could have worded my comments more carefully. The description of the heat as "excess" assumes that the only input is the electrochemical current+voltage. Is that better?"
They do not assume this. With an open cell they run the effluent gas through a mass spectrometer to determine exactly what is coming out. With a closed cell they test samples of the electrolyte. Electrolysis is the only source of electrical or chemical energy that goes into the cell. No fuel is present before the experiment, nothing is formed (except O2 and D2 obviously) and no other chemical fuel is found during or after the run. Obviously the D2 and O2 is accounted for.
"Regarding the analytical chemistry, there are multiple groups working on this stuff that disagree amongst themselves about whether there is tritium, helium, neutrons, etc."
Which groups do you refer to? Tritium is very easy to detect. I do know of anyone who disputes the tritium findings at BARC, Los Alamos or Amoco for example. Helium is difficult but I have not read any papers challenging the findings at China Lake, SRI or the ENEA. Neutrons are the only disputed product as far as I know.
"My point is, if different groups disagree about whether there is tritium in the effluent . . ."
Which groups?
". . . then how much weight should I put on the statement that there is definitely no chance of chemistry going on."
If you propose that chemistry may be going on, please list a candidate chemical reaction. What reaction can produce, say, 100 MJ from 0.1 g of metal and 20 g of water?
"I wish the enthusiasts the best of luck. If this turned out to be a nuclear process, it would be incredibly exciting. I just think that my threshold for such a claim is really high."
If you assert that a chemical reaction from a few grams of material can produce 100 MJ then your threshold is low, not high. You seem far too open minded. I think the laws of physics & chemistry rule this out absolutely.
"It would require us to throw out just about everything we know about nuclear fusion (which is quite a bit)."
Schwinger and other expert disagree with you about that. I am not competent to judge. But I think it is much more likely that that laws of chemistry are well established than those of fusion physics. In other words, if we have to throw something out, the laws governing chemical reactions should take precedence over the plasma physics. Also the laws of thermodynamics, upon which all cold fusion calorimetry is predicated. I think it is highly unlikely that anyone will discover a reason why people like McKubre cannot measure 25 W excess heat, especially when there is no input power.
I meant:
ReplyDelete"I do NOT know of anyone who disputes the tritium findings at BARC, Los Alamos or Amoco for example."
Who do you have mind who disputes these results? How about Gozzi or Bockris? I have not read any critiques of them, but I have not read everything, after all.
I will grant, there are some marginal tritium claims.
DARPA/DoD, or the NSF should fund grants for some independent AMO people unassociated in their careers with anything related to cold fusion or electrochemistry to run some experiments to once in for all rule on cold fusion.
ReplyDeleteI'm sure Steven Chu probably knows some candidates for this sort of grant. ;)
anonymous wrote:
ReplyDelete"DARPA/DoD, or the NSF should fund grants for some independent AMO people unassociated in their careers with anything related to cold fusion or electrochemistry to run some experiments to once in for all rule on cold fusion."
That would be a huge mistake. Cold fusion experiments are extremely difficult. They require expertise in electrochemistry, materials, mass spectroscopy, calorimetry and other fields. Prof. Richard Oriani, one of the top electrochemists in the U.S., said that replicating cold fusion was the most difficult experiment he did in his 50-year career.
In 1989, several groups of nuclear physicist attempted to replicate cold fusion. They knew little about electrochemistry and unfortunately they did not consult with electrochemists. They made many major errors that precluded any possibility of success. From the point of view of an experienced electrochemist, what they did was equivalent to "finding a piece of gravel in the driveway and trying to make a semiconductor out of it."
This experiment only works when it is done by experts who devote anywhere from 6 months to 2 years of intensive effort to it. That is not surprising or unusual. Many experiments are like that, after all.
It could be made a lot simpler if the materials were improved, and people did not have to spend weeks or months fabricating and testing cathodes by hand. That is what the people at ENEA are working on. There was a brief video of that on 60 Minutes. Unfortunately to do that right would cost millions or hundreds of millions, and those people are working on a shoestring. I doubt they will make much progress in their remaining professional lives at this rate.
100 MJ over what length of time?
ReplyDeleteRe: disagreements about the chemical composition of materials pre- and post cycling, I spoke with Melich (certainly an enthusiast) face to face - I don't have references handy.
ReplyDeleteYou wrote:
ReplyDelete"100 MJ over what length of time?"
123 days. 17 W. 250% of input. See p. 9:
http://lenr-canr.org/acrobat/RouletteTresultsofi.pdf
Actually, that was a pretty big cathode: 100 mm x 2 mm rod. Not much surface area. You may have noted that the ENEA cathode McKubre showed is a thin foil. Lots more surface area but less mass overall.
Massive surface area with things like nanoparticles are the way to go, in my opinion.
Doug Natelson said...
ReplyDelete"Re: disagreements about the chemical composition of materials pre- and post cycling, I spoke with Melich (certainly an enthusiast) face to face - I don't have references handy."
Well, his people do a thorough job at chemical analysis. I just now uploaded a paper about that from Kidwall. As Melich says, what they do to those cathodes would make the angels weep.
Naturally, they find microscopic changes to the surface. You can see it: a thin film forms, and discolors the surface.
They are looking for what happens on the surface to form the NAE (nuclear active environment). But whatever that is, there ain't much of it. Microgram amounts of material I suppose. Whereas to explain the energy as a chemical reaction in some cases you would need several kilograms of the best chemical fuel in existence.
I did not mean to suggest that there are absolutely no chemical or physical changes. I just meant that the cell is not magically converting 30 ml of water into 2.8 liters of gasoline, to take an example from Mizuno.
Extraordinary claims demand extraordinary evidence.
ReplyDeleteCold fusion is extraordinary in many ways, even before Fleischmann&Pons. Like it or not, but I would need to see a lot more evidence to be convinced that something real is behind it.
60 minutes should have asked someone like Robert Park or a scientist of similar level to investigate the reports and provide the balanced "other side" of the story. They claim they contacted APS to help assign such "referee", but in fact APS denies they had anything to do with it.
Obviously, there are still many biased pro-cold fusion defenders, like Jed Rothwell here. I am clearly biased towards skepticism, as is Doug and most other scientists I know. It's healthy skepticism, considering the history of the field, the number of outlandish claims made and lack of concrete results over the past 20 years.
The burden of proof is on cold fusion researchers - not on the rest of scientific community to spend extraordinary amount of time and effort to disprove cold fusion claims.
Climate Progress has additional skeptical reaction to the 60 Minutes story. Included there is a link to a 2004 Re-review by DoE, in which most (but not all) of the reviewers found the evidence for excess heat, and especially for nuclear reactions, less than convincing.
ReplyDeleteAngry comment!!!
ReplyDeleteThanks for the link, Don.
ReplyDeleteAnother point that I should have made in the main post: the investigators can't tell if this is a surface or a volume effect. That is, you'd think that you'd be able to make several Pd pieces, say a few cm^2, prepared identically except having different thicknesses. Then one could compare the output of otherwise identical cells and establish whether the phenomenon scales with Pd area or Pd volume. Gadget-to-gadget variation is sufficiently large that this appears not to be possible.
Time will of course tell.
ReplyDeleteAs an experimentalist, when somebody tells me that every single parameter has to be just so in order to see something, it usually means either
(a) the claim is false
(b) it is useless to spend time on it
not to keep adding to this topic, but it appears that Michael McKubre, the central figure of 60 minutes report, has been claiming that he reproduced cold fusion findings of Fleischmann&Pons for quite some time now - prior to DOE's 2004 report he kept saying that he found evidence of cold fusion multiple times. So in 5-6 years since then, he is still at the same point in his research? I would have imagined that we would have more by now - maybe not device, but at least a highly reproducible experiment with all i's dotted and t's crossed.
ReplyDeleteAs a general rule, major discoveries in science come from conferences and refereed publications, when other scientists successfully reproduce the results and publish them. We have seen very fast developments in pnictides, graphene, metamaterials, magnetic semiconductors etc. - just to name a few. A few weeks or months after original work has been reported you have dozens of groups working on it. A year or two later you may have many hundreds of people and publications.
The real discoveries do not arise from 60 minutes reports.
IP, you're absolutely right, of course. Indeed, the examples you mention are all nasty materials problems, and lo and behold, they've been worked out in relatively short order. The idea that after twenty years there's still some "magic" prep for Pd surfaces is pretty silly. There are well established techniques for getting clean surfaces, and they really aren't that subtle. The fact that there's voodoo here is another sign that all the action probably has to do with some surface contaminant rather than Pd itself. Indeed, I've seen electron micrographs complete with EDX elemental mapping of Pd surfaces from these cells, and they show little patches of non-Pd stuff (e.g., carbon) on there.
ReplyDeleteI wouldn't give any credit at all to cold fusion except that my hero, Julian Schwinger, was at least agnostic about it if not a believer.
ReplyDeleteAs far as the difficulty in reproducibility, I'm reminded of early laser experiments. People made multiple lasers to the same spec, some worked, some didn't. Designs were published, others couldn't get them to work.
Eventually, as the technology advanced, the bugs got worked out and now anyone, more or less, can build a laser. But for a while, you had to invite a guy over to your lab who had got one to work before, then he did things like changed the lengths of your power supply wires and eventually got it to run.
The book, "Gravity's Shadow", (which was a fascinating read to me) is about gravity wave experiments. It discusses the inherent difficulty of reproducing difficult physics experiments and compares the laser problems with the early gravity wave problems where a guy (who taught my GR class, hence my interest in the book) kept finding gravity waves that no one ever reproduced.
Lasers are not a surface effect and so they were a lot easier to get running. If cold fusion is true, then the basic underlying problem is that in the absence of a theory, they don't know what they are doing.
17W is small - why can't they scale up the effect to get sustained power of > 100W something enough to be unambiguous
ReplyDeleteYou (Jed) also say skeptical nuclear physicists and electrochemists didn't get together on this - Koonin with a group of Caltech nukers got together with Nate Lewis and dropped everything for 6 months to look for the effect.
They found nothing.
You want to claim they didn't know what they were doing?
Jed Rothwell claims "cold fusion" that
ReplyDelete1) produces 380,000 times the energy yield of combustion per fuel atom (D+D vs. C), but
2) cannot produce enough "excess" energy to be readily detectable
is not crap. Res ipsa loquitur.
Uncle Al wrote:
ReplyDelete"Jed Rothwell claims cold fusion that
1) produces 380,000 times the energy yield of combustion per fuel atom (D+D vs. C), but
2) cannot produce enough 'excess' energy to be readily detectable"
Cold fusion is readily detectable. Some cells produce 20 to 100 W with no input power. That's palpable. Not only is it readily detectable, it is impossible to miss.
However, you are confused. Just because a sample produces 380,000 times the energy yield of combustion per fuel atom, that does not mean it is easily detected. A sample of impure radium or uranium produces millions of times more energy per reaction, but so few reactions that the heat may be impossible to measure even with the most sensitive microcalorimeter. There is no connection between the intensity of the reaction per atom and the ease of detection.
If it is chemistry, and I am completely open to it being chemistry, then what is the process? If I understand this, you water (heavy), palladium, and electricity.
ReplyDeleteWhat is the chemistry of this?
There is plenty of evidence, start with the war on cold fusion YouTube video, if you want to see my work go to griffinsofdawn.com/general forums/ page 6,7, or 8 now titled free energy source.
ReplyDeleteI have to say I am very disappointed at people and there attitudes to new science, it has become a religion and new science is ridiculed and suppressed. We could have had free energy for at least 60 years.
If you view some of my other topics you can see how our current theory of orbits is wrong, our current theory of electrical systems is wrong as well, i also show how to charge a battery for free in one of my other topics.
And of course all my work on my water fuel cells is there free for anyone to view. There are now people in the tens of thousands utilizing some of this energy in there cars already.
I have seen ORMES build up on my cathode, i have tested them for weight loss, i run a negatively charged cell that produces more of this energy than even there high voltage cold fusion systems, even hydrogen on demand creates some of this energy.
The negatively charged fuel cells remove electrons, this creates more of this energy more efficiently.
You can also view the Joe cell.
I said years ago that if these scientist negatively charged there water first (drain some electrons) they would solve there replication problem, now they are aware of an incubation period, now I will say if they negatively charge there water first they will not have such a long incubation period.
Someone wrote:
ReplyDelete"If cold fusion is true, then the basic underlying problem is that in the absence of a theory, they don't know what they are doing."
Reality is like that, isn't it? Tough. Very tough. We are all floundering around in the absence of a COMPLETE set of fully-validated theories that explain everything.
Funny thing though: the theories are forthcoming. Some are well along in their construction. Others not so much, but promising. Partially-constructed theories inform empirical study, which results in better, more-refined theory. Sometimes research must take place for a long time without even a good clue as to what the underlying explanatory framework might be; e.g. genetics before the discovery of the double helix.
The fact that a theory is absent is (obviously!) no reason to reject the research. But that obvious fact will not, of course, stop the professional debunkers and pseudo-skeptics from rejecting it on that basis.