Cold fusion

• 1. Introduction

  ›

  Cold fusion is the name for a nuclear reaction that would happen at or near room temperature. Ordinary fusion needs millions of degrees. It powers the stars, hydrogen bombs and prototype fusion reactors. In 1989, two electrochemists at the University of Utah announced something startling. A small tabletop apparatus filled with heavy water, they said, had given off heat that chemistry alone could not explain. The announcement raised hopes of a cheap and abundant source of energy.

  Within months, most scientists had written the claim off. The subject soon earned a reputation as pathological science. Even so, a small community of researchers still works on it, often under other names, and no accepted theory says how it could happen.

  Where did the idea come from, and why did it look so plausible to serious scientists? What exactly did the physicists find wrong with it? And why does anyone keep trying?

  143956

• 2. Palladium Dreams

  ›

  Palladium's appetite for hydrogen was recognized in the nineteenth century by Thomas Graham. In the late 1920s, two Austrian-born scientists, Friedrich Paneth and Kurt Peters, made a claim. Hydrogen, they said, turned into helium when it soaked into finely divided palladium at room temperature. They had reason to hope. Palladium can absorb up to 900 times its own volume of hydrogen gas, and Germany then needed helium to fill zeppelins. Paneth and Peters later retracted the report, saying the helium they measured had come from the surrounding air.

  In 1927, the Swedish scientist John Tandberg reported that he had fused hydrogen into helium in an electrolytic cell with palladium electrodes. He applied for a Swedish patent on "a method to produce helium and useful reaction energy." The application was denied. The retraction by Paneth and Peters counted against him, and he could not explain the physical process. After deuterium was discovered in 1932, Tandberg switched to heavy water. His last experiments resembled the Utah work closely, yet Fleischmann and Pons had never heard of them.

  The phrase "cold fusion" itself appeared as early as 1956, in a New York Times article about Luis Alvarez and muon-catalyzed fusion, a different process. In 1986, Paul Palmer and then Steven Jones of Brigham Young University used the phrase for "geo-fusion." That meant possible fusion of hydrogen isotopes inside a planetary core. Palmer, a geologist, persuaded Jones that the helium-3 found naturally on Earth might come from fusion inside catalysts such as nickel and palladium. Their team independently built the same setup the Utah pair would use: a palladium cathode in heavy water, loaded with deuterium by electrolysis.

  Jones had already coined his own term, "piezonuclear fusion," in a paper with Clinton Van Siclen submitted in 1985. In July 1987 he published an article titled "Cold nuclear fusion" in Scientific American. Soon his name would turn up on a grant proposal sent to the Department of Energy.

  1112135

• 3. The Press Conference

  ›

  Martin Fleischmann of the University of Southampton and Stanley Pons of the University of Utah suspected that electrolysis might squeeze deuterium into palladium. They thought the compression could be tight enough to trigger fusion. They passed current through heavy water around a palladium cathode inside a calorimeter, an insulated vessel built to measure heat. The current ran continuously for many weeks. Most deuterium bubbled away, joining oxygen from the anode. Usually the power going in matched the power coming out, and the cell sat near 30 degrees Celsius.

  In some experiments, however, the temperature suddenly climbed to about 50 degrees with no change in input power. These hot phases lasted two days or more and repeated several times. Eventually a given cell stopped producing them.

  In 1988, the pair applied to the Department of Energy for money for a larger series of experiments. Until then they had paid for a small device with $100,000 out of their own pockets. One reviewer of the proposal was Steven Jones. He and the Utah team met on occasion to share techniques. Fleischmann and Pons described considerable "excess energy" and believed it was commercially valuable and patentable. Jones was measuring neutron flux, which had no commercial value. The teams seemed to agree to publish together, although their accounts of a meeting on the 6th of March differ.

  By mid-March 1989, both groups were ready. Fleischmann and Jones planned to meet at an airport on the 24th of March and send their papers to Nature by FedEx. The University of Utah, eager to establish priority, pushed its pair to go public first. They held a press conference on the 23rd of March. The press release promised publication in Nature, but the paper went to the Journal of Electroanalytical Chemistry. Jones, upset, faxed his own paper to Nature afterward.

  The timing helped the story spread. High-temperature superconductivity had been discovered in 1986, which left scientists more open to unexpected results that no theory could yet explain. Some recalled the Mossbauer effect, which had also been a surprise but was quickly replicated and explained. Adults still remembered the 1973 oil crisis. Global warming was becoming notorious, and acid rain and strip mining were on people's minds. The Exxon Valdez oil spill happened the day after the announcement.

  At the press conference, Chase N. Peterson, Fleischmann and Pons repeatedly assured journalists that cold fusion would solve environmental problems, using only seawater as fuel. They said the results had been confirmed dozens of times. The release quoted Fleischmann: "the discovery will be relatively easy to make into a usable technology for generating heat and power."

  The experimental protocol, though, had not been published. No other laboratory could simply copy it.

  274175215

• 4. Fusion Confusion

  ›

  On the 10th of April 1989, a group at Texas A&M University published results of excess heat. Later that day, a group at the Georgia Institute of Technology announced neutron production. It was the strongest support yet, because neutrons were detected in a reputable lab. Pons was acclaimed at a meeting of the American Chemical Society on the 12th of April. The next day, Georgia Tech retracted, explaining that its neutron detectors gave false positives when heated.

  Elsewhere, physicists were failing to reproduce the excess heat. Nathan Lewis of the California Institute of Technology led one of the most ambitious efforts, trying many variations without success. CERN physicist Douglas R. O. Morrison said "essentially all" attempts in Western Europe had failed. Robert Huggins of Stanford reported early success and became the only scientific support for cold fusion at the congressional hearings on the 26th of April. When he presented his data, the excess heat was only one degree Celsius, which chemical differences between heavy and light water could explain. He had measured no radiation. The press called the whole episode "fusion confusion."

  Meanwhile, the Utah pair held firm. The university asked Congress for $25 million, and Pons was due to meet representatives of President Bush in early May. On the 30th of April, The New York Times declared cold fusion dead and called it a circus. On the 1st of May, the American Physical Society held a session in Baltimore. Eight of the nine leading speakers called the original claim dead. Johann Rafelski abstained. Steven E. Koonin of Caltech blamed "the incompetence and delusion of Pons and Fleischmann," and the audience gave him a standing ovation. Morrison was the first to call the episode pathological science. The Washington meetings were cancelled on the 4th of May.

  Only the Texas A&M tritium results kept the idea afloat after the 8th of May. Then they fell too. In June 1990, science writer Gary Taubes accused group leader John Bockris and a graduate student in Science of spiking the cells with tritium. Researcher Kevin Wolf blamed contaminated palladium electrodes, and a university panel found contamination and measurement problems more likely than spiking. Bockris never won faculty support to resume his work.

  The official verdicts arrived too. Nature published critical papers in July and November 1989. A Department of Energy panel reported in November that the results were not convincing evidence of a useful energy source and opposed special funding. Yet in August 1989 the state of Utah put $4.5 million into a National Cold Fusion Institute. In March 1990, physicist Michael H. Salamon and nine co-authors reported negative results, and a lawyer for Pons and Fleischmann demanded a retraction under threat of a lawsuit. He later apologized. The institute listed 92 groups from 10 countries reporting excess heat in September 1990. It refused to share any evidence of its own, citing patents. It closed on the 30th of June 1991 after running out of money.

  Pons left Utah on the 1st of January 1991 for Europe. From 1992 he and Fleischmann worked at the Toyota IMRA laboratory in France. Fleischmann went to England in 1995. The contract with Pons ended in 1998 after $40 million produced no tangible results.

  7576162224

• 5. Physics and Measurement

  ›

  A single number captures the physicists' first objection: 50 orders of magnitude. Extrapolating from known fusion rates, uncatalyzed fusion at room-temperature energies would run that many times too slowly to explain the reported heat. Positively charged nuclei repel each other strongly. A muon can pull deuterium nuclei 207 times closer together, which is why muon-catalyzed fusion works. Inside a palladium lattice, though, deuterium nuclei sit farther apart than in deuterium gas.

  Fleischmann and Pons had calculated a pressure of 10 to the 27th atmospheres inside the metal. Real experiments reach a loading ratio of one deuterium atom per palladium atom, which corresponds to only 10,000 to 20,000 atmospheres. John R. Huizenga said they had misread the Nernst equation.

  The reaction products posed another puzzle. Ordinary deuterium fusion goes through an unstable intermediate with two main exits, each about half of the time. One releases a neutron with helium-3, the other a proton with tritium. Only about one in a million takes the third exit, producing helium and a gamma ray. At one watt, the usual pathways would flood the room with about a trillion neutrons per second, a level fatal to the researchers. Fleischmann and Pons reported 4,000 neutrons per second plus some tritium. Reports of helium without neutrons or tritium would demand branching ratios that contradict every other experiment.

  Gamma rays were missing, too. In April 1989 the pair published a preliminary note. Its spectrum showed a gamma peak without its matching Compton edge, which suggested they had erred in claiming fusion byproducts. Later work reported X-rays, helium, neutrons and transmutations, but levels stayed near background. Helium in particular could not be separated from trace contamination by air.

  The heat itself was shaky as well. In the Utah experiments, the inferred excess ran at 10-20 percent of input. Nathan Lewis found that the excess in the original paper was not measured but estimated from data showing no excess. Calorimetry rests on assumptions. Fleischmann and Pons assumed electrolysis was nearly 100 percent efficient, but hydrogen and oxygen recombining inside the cell would release heat and distort the calibration. Texas A&M also discovered bad wiring in its thermometers.

  Reproducibility never rescued the claim. Groups that saw an effect found that some cells worked while identical ones did not. The 2004 panel noted that even proponents "assert that the experiments, for unknown reasons, are not consistent and reproducible at the present time."

  Researchers such as Michael McKubre proposed a reason. The cell must be loaded to at least a one-to-one ratio. That ratio is hard to reach, because the pressure cracks some palladium and lets the deuterium escape. Fleischmann and Pons never disclosed their ratio. By 2002 the batches of palladium they used no longer existed, because the supplier had changed its manufacturing process.

  2567665383

• 6. Pariah Field

  ›

  In 1989, cold fusion was the scientific topic with the most published papers of any discipline, according to the ISI. After 1990 it fell off the charts. Scientists left the field and journal editors declined to review new papers. Fleischmann's last paper, in Physics Letters A in 1993, was among the last of his reports formally challenged by a skeptic. In 1994 Caltech physicist David Goodstein called cold fusion "a pariah field, cast out by the scientific establishment." Its practitioners felt under siege, he said, so they criticized each other little. In that climate, "crackpots flourish."

  Nobel laureate Julian Schwinger declared himself a supporter in the fall of 1989. When Physical Review Letters rejected his theoretical paper "Cold Fusion: A Hypothesis," he felt so insulted that he resigned from the American Physical Society. The journal Fusion Technology kept a permanent section for cold fusion papers from 1990 until editor George H. Miley retired in 2001. Supporters launched their own periodicals, including Fusion Facts, Infinite Energy Magazine and New Energy Times.

  The community built its own conferences too. The International Conference on Cold Fusion first met in 1990 and has gathered every 12 to 18 months since. Skeptics stopped attending, apart from Douglas Morrison, who died in 2001. In 2004 the International Society for Condensed Matter Nuclear Science was founded. The conference took a new name, then reverted to the old one in 2008. Researchers often prefer "low-energy nuclear reactions," because the label avoids implying that fusion is happening. Sociologist Bart Simon argues that the "cold fusion" label still gives the field a collective identity.

  A 1991 review by a proponent counted about 600 scientists still at work. The Boston Globe estimated in 2004 that only 100 to 200 remained, most with damaged careers. The American Physical Society began including cold fusion sessions in 2006, while stating that this was no softening of skepticism. The American Chemical Society added invited symposia in 2007. Its program chair, Gopal Coimbatore, said that without a forum the matter would never be discussed.

  79156962

• 7. Governments Revisit

  ›

  In August 2003, Energy Secretary Spencer Abraham ordered a second Department of Energy review. A letter from MIT's Peter L. Hagelstein and a wave of new papers prompted it, including a two-volume report from Navy researchers in San Diego. The 2004 reviewers were split approximately evenly on whether the experiments produced heat. Most agreed the effects were not repeatable and had not grown in a decade. They recommended no federal program, only funding for individual well-designed studies. Proponents saw a "rosier spin," and in 2009 particle physicist Frank Close told the BBC that the old problems persisted.

  Italy's national agency ENEA funded Franco Scaramuzzi's work on deuterium-loaded metals. In 2006-2007 it launched a program that claimed excess power of up to 500 percent, and in 2009 it hosted the 15th cold fusion conference.

  Japan's trade ministry spent US$20 million on a "New Hydrogen Energy" program between 1992 and 1997. When it ended, director Hideo Ikegami, once a proponent, said they had not achieved what was first claimed. Independent work continued through the Japan C-F Research Society. Yoshiaki Arata of Osaka University reported excess heat from deuterium gas in palladium and zirconium oxide.

  India halted work at the Bhabha Atomic Research Centre in the 1990s. In 2008 the National Institute of Advanced Studies recommended reviving it, though progress stalled. In 2015, the journal Current Science published a special section of 33 cold fusion papers.

  In the United States, millionaire Sidney Kimmel was moved by a 60 Minutes interview with physicist Robert Duncan. In February 2012 he gave $5.5 million to the University of Missouri for an institute devoted to hydrogen in palladium, nickel and platinum. In May 2016, the House Armed Services Committee asked the Secretary of Defense for a briefing on the military utility of LENR. Nature reported in May 2019 that Google had spent about $10 million. Scientists at MIT, Lawrence Berkeley National Laboratory and other labs worked for several years to set rigorous protocols. Their conclusion was that cold fusion did not occur. In 2021, Navy, Army and NIST scientists announced a new coordinated study.

  37731376

• 8. Patents and Pop Culture

  ›

  On the 12th of April 1989, MIT announced its own patent applications, based on the theory of Peter L. Hagelstein, who had been sending papers to journals for a week. The University of Utah appears to have rushed its announcement to claim priority over the discovery and its patents. In December 1993 it licensed its cold fusion patents to ENECO, a company formed to profit from them. In March 1998 it said it would stop defending them.

  The U.S. Patent and Trademark Office now rejects cold fusion claims on the same grounds it uses for perpetual motion machines: that they do not work. Esther Kepplinger, deputy commissioner of patents, said as much in 2004. A federal court upheld such a rejection in 2000. Some inventors rename their work. One holder of three patents rewrote his applications to stress electrochemistry so that electrochemists, not nuclear experts, would review them. In 2004 Melvin Miles received a patent after removing the words "cold fusion" from the text. The European Patent Office has granted at least one. A patent holder said his three had been valuable in attracting investment, since the public sees a patent as a stamp of approval.

  Popular culture adopted the phrase as shorthand for impossible science. The 1990 Michael Winner comedy Bullseye!, starring Michael Caine and Roger Moore, referenced the Utah experiment and was called "appallingly unfunny."

  The phrase turned up as a joke on Murphy Brown and The Simpsons, and in a 1995 Pepsi Max advertisement. It also named the Adobe ColdFusion software and a brand of protein bars.

  Thrillers borrowed it more seriously. The 1996 film Chain Reaction shows a variation on the principle. The 1997 film The Saint parallels the Fleischmann and Pons story with a different ending. Bart Simon suggests it pushed cold fusion further into science fiction. An Outer Limits episode in 1998 and the 2000 series Life Force used it too. In the 2023 video game Atomic Heart, cold fusion drives almost every technological advance.

  6162707863