The chemists claiming to have solved the world’s energy problems with cold fusion, Stanley Pons and Martin Fleischmann, made a somewhat unlikely pair. Pons was a quiet and modest man from a small town in North Carolina. Fleischmann was an outgoing European who exuded confidence and was almost old enough to be Pons’ father. The two had met while Pons was completing his Ph.D. at the University of Southampton in England, where Fleischmann was a professor. Pons admired Fleischmann’s intelligence and ingenuity, and Fleischmann soon became his mentor and friend. The two remained close over the years, as Pons moved from a graduate student position into a professorship at the University of Utah. Shortly after Pons took up his post as professor, the two began to collaborate on research projects.

The idea behind their cold fusion ​​experiment was sparked by another one of Fleischmann’s studies. In the late 1960s, Fleischmann had been using palladium, a rare metal, as a key ingredient to separate hydrogen from deuterium. In those experiments, he saw firsthand how palladium can absorb unusually large amounts of hydrogen — about 900 times its own volume. That’s a bit like using a single kitchen sponge to mop up 30 gallons of spilled milk! This amazing absorption power is due to a chemical reaction on the surface of the palladium that draws hydrogen inside the metal. Because hydrogen and deuterium are so similar (differing by just one neutron), the same reaction occurs with deuterium — it can also be sucked up by palladium in surprisingly large amounts. Fleischmann reasoned that since the deuterium absorbed by palladium undergoes a dramatic reduction in volume (by a factor of about 900), the deuterium atoms must be squished together inside the palladium. He began to wonder if a similar process could be used to force deuterium atoms close enough to fuse and release energy …