I took some physics, but I am not a physicist, but I can't see how you can have cold fusion because of the energy involved in slamming crap together. Just an opinion,
Cold Fusion does exist. Muon Catalysed Cold Fusion was demonstrated in the late 1940s. Interestingly the maximum efficiency of the reaction is at around 1000 Kelvin (~700 C) making it perfect for boilers.
A
muon is a heavy particle with a charge of -1, the same as an electron. Hence It can behave like an electron, so when interacting with a couple of heavy hydrogen nuclei it can bind them just like an electron binds a hydrogen molecule, except much more tightly because the muon is much heavier. In fact it brings the nuclei together close enough to fuse.
As a catalyst, the muon is not consumed in the process and is released where it can go on to catalyse another reaction. Despite its short two microsecond lifetime, a single muon can catalyse hundreds of fusion reactions.
Unfortunately it takes a lot of energy to create a muon in a particle accelerator, more than is released in the fusion reactions by a couple of orders of magnitude. If an efficient way to create muons were to be found it would truly be the holy grail of energy production.