Shrink-wrapping nuclear energy : Cold fusion once again promises to make nuclear plants compact and less dangerous

How do you bring respect back to a discredited field? One way is to change its name as new evidence accumulates. This method works particularly well if the original name was ill-conceived and non-representative — like cold fusion, a name given more to interest the public than to describe a field accurately. So when scientists found more and more data to support their claims, one of the first things they did was to find a ponderous and dignified name: Low Energy Nuclear Reactions (LENR).

Most scientists as well as the public thought that cold fusion was dead and buried in the early 1990s, just a few years after two scientists announced its discovery at a press conference. Now the phenomenon is staging a comeback, but with the name Low Energy Nuclear Reactions. However, the major change in the field is not in the name; it is in the number of scientists involved and the variety of methods employed. Cold fusion was announced by two scientists, while LENR is independently being achieved by several. Says Gopal Coimbatore, professor of physics at the Texas Tech University, US, “The results are quite convincing.” Coimbatore recently chaired a session on LENRs at the American Chemical Society meeting in Chicago.

Fusion is the process in which two atomic nuclei combine to produce a new element and energy. Scientists so far thought that to bring two nuclei together needed high temperatures. But now evidence seems to indicate otherwise. At the University of Illinois in Urbana Champaign, George Miley packed heavy hydrogen tightly into clusters between thin films and watched heat being generated. He also observed the formation of new elements, a process that is the signature of fusion. At the Space and Naval Warfare Systems Centre in San Diego, Pam Mosier-Boss and Stanislaw Szpak found similar evidence in experiments at low temperature, as did Melvin Miles at the University of LaVerne in California. Miles is now a collaborator of Martin Fleishman, who was one of the scientists to announce the achievement of cold fusion in 1989.

In 1989, Pons and Fleishman announced that they had achieved cold fusion

Fleishman and Stanley Pons created a sensation by announcing that they had achieved cold fusion through electrolysis — the splitting of water by electricity. They used heavy water (which has heavy hydrogen or deuterium in place of of normal hydrogen) instead of normal water. Their apparatus heated up suddenly once in a while. This heating could not be explained by any conventional means, and was evidence of fusion, said the scientists. But their experiments were not immediately reproducible. All scientists thought that what they saw was nothing more than a chemical reaction. Since the scientists chose to announce their results through a press conference, their work was further discredited. They may have been keener to establish priority than to prove their work.

However, as most scientists turned away from cold fusion, a few kept beavering at it diligently, some as extensions of their work in other fields. For example, George Miley had been working on thin films for many years. In particular, he had worked on multilayered thin films that sometimes created unusual conditions, in terms of atomic-sized pockets where atoms are packed together. Deuterium atoms packed very tightly might have fused. Miley observed heat and many unusual elements like selenium, which can come only from fusion.

His experiments are now more interesting from a scientific point of view than as an energy source. Why did the atoms fuse? Even if they come close together, as they do in his experiments, they still have to overcome the powerful Coulomb force — electrical repulsion — before fusing. There is probably an answer. Says Miley, “I think they overcome the Coulomb barriers through tunnelling.” This is the strange phenomenon in the quantum world where particles seem to dig through barriers. Miley has to do much work before making this a continuous energy source.

Miley presented his work at the American Chemical Society meeting. Among the other scientists presenting their work was Pam Mossier-Boss. She and her colleague Stanislaw Szpak used electrolysis of heavy water to achieve fusion, or so it appears. The electrode they used was made of palladium. Deuterium atoms from the heavy water accumulated within the lattices — regular arrangements of atoms — of palladium and were packed close together. Some of them may have fused.

We cannot know directly. Like Miley, Mossier-Boss and Szpak also found excess heat and the element tritium and X-rays. This is evidence of nuclear fusion. They have also published papers in journals. “Their results can be explained only by invoking low energy nuclear reactions,” says Coimbatore.

In the last two years, because of similar results coming from many research groups, the US department of energy officials have started to develop interest in the phenomenon. After all, experiments at the frontiers need funding. And the officials’ interest can translate into funding. The sooner this happens, the better it will be for the scientists engaged in this work.