Has nothing to do with the means of producing energy
Well, this I believe was one of the last Missing Adventure Books that I have read (and while I would not be adverse to reading more, it really comes down to finding them, and I suspect that, with the exception of scouring second-hand bookshops, it may be expensive, particularly if I am ordering through Amazon). Anyway, this book involves Tegan, Adric, and Nyssa (whom I vote to be the Doctor's sexiest companion, at least for the older series, though I also quite liked Jo, Liz, and Romana II) and is set between Castrovalva and Four to Doomsday, but is also includes the Seventh Doctor from one of the novels, so in a way it is one of those two Doctors adventures.
The story takes place on an ice world which is ruled by a scientific elite that keeps the rest of the planet oppressed. However the planet, being an ice planet, is also a ski resort. This adventure is set quite a ways into the future there, where it appears that humanity has colonised vast swaths of the galaxy. It is always interesting to hear the Doctor praise humanity and its resourcefulness, in the belief that humans, deep down, are a good race of people. The Doctor always mentions that Earth is his favourite place, and humans are his favourite peoples.
I do not believe that this book has anything to do with the energy producing method called Cold Fusion, but I will speak a bit about it. As from my understanding (at least from year 12 physics) that fusion as a means of generating electricity was not possible, namely because the technology to enable the construction of a magnetic containment field simply has not been developed. Fusion power involves fusing two hydrogen atoms, which results in a huge burst of energy, however the amount of energy that is required to fuse the atoms requires an atomic explosion (fusion bombs, or hydrogen bombs, are detonated through the use of a fission bomb, otherwise known colloquially as atom bombs – both are nuclear weapons). However, the concept of cold fusion is that the fusing of the hydrogen atoms can be performed without resorting to nuclear power. While the idea may be enticing, as far as I believe, it is currently impossible.
