>>6427141>>6428353MechE here, specializing in mechatronics at the moment so I don't have as much real world experience as much as understanding of the design.
Obviously you are correct in that you would need a ton of energy to even think about moving an arm, let alone simultanously moving an entire body. Unforunately solar wouldn't do the trick as they would be the most prone to be destroyed and their energy gain is fucking atrocious. What you would need is a fusion reactor, as they are super safe and have the potential to give you the energy you need (hopefully Germany gets theirs working).
As when this will come about, hopefully in our lifetime but most likely not. Exoskeletons and automated air support (hopefully automated bipedals!) are first. Large mechs will most likely come in when most security/armies are automated and larger mechs will serve more of a last resort / center node to give human mech pilots direct control. Mechs right now are just too much of a money sink/money lost potential to even think about sadly.
