Cold fusion: Now there’s an idea I hadn’t thought about in a while. It came back onto my radar in spring 2026. I had written an article on how scientists tend to be risk averse, and Huw Price (opens a new tab), a philosopher at Trinity College at the University of Cambridge, responded to it on Bluesky, citing a paper he’d recently co-authored on attitudes toward cold fusion. He thinks scientists have been overly dismissive not only of cold fusion, but also of the claim that they have been overly dismissive of cold fusion. As if to prove his point, a journal had just rejected his paper. I’ve long admired Price’s work on the nature of time and causation, so I was intrigued.
When the cold-fusion controversy erupted in 1989, I was in the middle of backpacking off the grid for six months. (You could do that back then.) By the time I caught up on the news, it was over. In March, two chemists had called a press conference to announce a simple tabletop experiment that released too much energy to be a mere chemical reaction. They said it had to be nuclear: hydrogen nuclei fusing to form helium. It promised limitless clean, cheap power. Physicists were stunned. That sort of thing wasn’t supposed to be possible under such pedestrian conditions. Politicians proclaimed the end of all our energy woes. But then labs across the globe tried to replicate the experiment and couldn’t, and an almighty takedown ensued. The whole thing only lasted a few months. Not having experienced the episode in real time, and being a contrarian by nature, I initially sympathized with the plucky maverick scientists. But then I read about their rookie mistakes, their fudging of a crucial graph, and their threats of lawsuits against skeptics. Experiments that initially corroborated the results were retracted, in one case amid indications of deliberate spiking with fake fusion products.
Although cold fusion was a pathological case, fusion in general has been a graveyard of dreams. I grew up on the dream it evoked. Whether it occurs at room temperature, as it was supposed to have done in the cold-fusion episode, or at center-of-the-sun temperatures, as in conventional thermonuclear reactors (and bombs), fusion doesn’t require strip-mining (and disposing of) uranium or escorting oil tankers through the Strait of Hormuz. All you would need, ideally, is a bit of seawater. Fascinated, I once built a “fusor” in my basement based on an article (opens a new tab) in Make magazine. Fusors are real, the one legitimate tabletop fusion technology. In them, a high voltage creates a hot plasma that smashes nuclei together. My unit didn’t achieve fusion, but with work it could have, although it would have produced negligible power. I loved showing guests its glowing purple plasma, but the more I learned about fusion, the more a sense of disillusionment grew in me. A couple of years later, a friend at a private fusion company gave me a tour of an actual experimental fusion reactor. It was complex and costly. So much for cheap. It produced intense, deadly neutron radiation. So much for clean. And it required tritium fuel, which does not occur naturally and has to be manufactured. So much for just a bit of seawater.
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