Asking this is like asking how long it should take for a sperm cell to swim across the Atlantic Ocean. The EMD is simply not applicable to scales where RTGs ar

Asking this is like asking how long it should take for a sperm cell to swim across the Atlantic Ocean. The EMD is simply not applicable to scales where RTGs are used, much as a 5MW maritime diesel turbine is not applicable to swimming motions of a biological cell. The power density of Voyager is a hundred times lower than what an EMD ship would need.