Cold fusion
Cold fusion is a popular name for an effect resulting in apparent excess heat, that some scientists have claimed could be produced from a nuclear reaction, mechanism unknown, near room temperature.
In 1989, electrochemists Martin Fleischmann and Stanley Pons of the University of Utah claimed to have produced such an effect loading a palladium cathode through electrolysis in heavy water, and some speculated that this might possibly become a source of cheap energy in the future.
After Fleischmann and Pons made their claim, a number of attempts to replicate the effect failed, and the claim was generally discredited. However, work continued, and Mike McKubre of Stanford Research International, and Miles and Bush at the United States Navy China Lake Research Laboratory, showed that a deuterium to palladium loading ratio of greater than 90% was needed to see the effect. The initial failures at MIT and CalTech used loading of well under 80%.
Further it has been shown that helium, in connection with the Fleischmann-Pons Heat Effect, is produced with a ratio to the anomalous heat that is commensurate with the ratio expected from some form of deuterium fusion to helium (though this ratio would be found with any reaction that starts with deuterium and ends with helium). This field is being actively researched today (circa 2012).
The field has been covered in many academic publications in recent years, including a review by Edmund Storms, "Status of cold fusion (2010)," Naturwissenschaften, October 2010. (preprint)
Research is ongoing in many laboratories around the world. There are also companies claiming to have working demonstration devices, claiming power levels that could see commercial usage; however there is no open independent evidence that these devices work, and some cold fusion researchers are skeptical of the claims.
The field has expanded from deuterium in palladium to also include hydrogen in nickel and nickel nano-powder, low energy glow discharge experiments and transmutation experiments (mostly in Japan). Research funding sources in the US include the Defense Advanced Research Projects Administration (DARPA), and the Department of Defense, Threat Reduction Agency.
The next international conference will be the 17th International Conference on Cold Fusion in Deajeon, Korea, August 12-17, 2012.