1. If something's expensive enough, that turns into manpower and then energy use as you look at the whole supply chain.

2. The ratio doesn't really matter once it hits double digits. If something outputs 100 energy units, the difference between it costing 10 energy units to build versus costing .01 energy units to build isn't a game changer. The important number is that almost all the energy it makes is "profit". And if you can make a solar panel output a few percent more energy, that matters more than getting the energy cost to 0 and having an infinite ratio would matter. All else equal, a solar panel that costs 4kWh to make and has a 1000x return is worse than a solar panel that costs 400kWh to make and has a 15x return.