What we call "Price of Energy" is in fact not the real price for the energy.
Why not?
Because Energy can neither be created nor destroyed.
If energy can not be created it can only be transported to exchange it for money.
What does this mean to the economic theory, where we have a small amount of the cost share reserved now for "energy"?
Paying for energy therefore is not paying for the energy - it is paying for the "transport of energy" to make the energy available in our economic system or paying the gate keeper of an energy containing system.
But all energy available is already out there in the nature - we can only take it and pay for the delivery, but not pay for the energy itself.
So, the natural price of energy is zero since it is a necessary and an external ressource into any given economic system.