Lochons (local charged bosons or local electron pairs) can form on D+ to give D- (bosonic ions) in Palladium Deuteride in the solid state. Such entities will occur at special sites or in linear channel owing to strong electron-phonon interaction or due to potential inversion on metallic electrodes. These lochons can catalyze D- - D+ fusion as a consequence of internal conversion leading to the formation of He-4 plus production of energy (Q=23.8 MeV) which is carried by the alpha particle and the ejected electron-pair. The reaction rate for this fusion process is calculated.