If you add up the energy inputs to create and supply the consumeable ingredients with the energy to run it, can it run off of solar cells with equivalent surface area so they just consume sunlight? Needs to be truly energy-neutral to be unequivocally useful. Burning more coal to use than it takes out, or hastening the day that alpha and gamma radiation screw us all up, aren’t acceptable. Of course, steps on the right path are to be celebrated.