I have been thinking on 'energy consumption'.
To use a power plant, or to move your state of awareness, is simply a movement, or shift, of the AP. To move to a far off location, to remain there for awile, and then to move back, appears as if we have lost 'energy', however to me it is simply shifting back to our original position, or another spot. This is the reason, in my mind, that we use the plants, to attain great shifts, and learn to examine them, gaining cohesion in these new dreaming positions, as well as observing the movement itself. It is no different to me then dreaming a fantastic dream then waking up in disappontment.
It is very important to stalk ourselves, as we are moving, to be aware of what is moving us, and where. If we 'come back' thinking we have lost it all, or that we are sad, depleted, or whatever, then surely that is the 'position' we are moving ourselves to. I find that it doesn't seem like 'energy', but what I am focusing my attention on, or where I am placing my power.