I Discovered an amazing thing the other day... Usually, I project and it will never last more than 10 min... :/ For no reason I'd leave my astral body and wake up physically, or just start dreaming. One reason for this i have heard before is because we run out of energy. If we draw in energy when we're physically awake, I wondered if I could do it in the Astral. When I first projected, I just imagined a waterfall type setup, except it poured energy instead of water. I just stood underneith it for a few seconds until I felt satisfied, and I projected for a good three hours it seemed. I had my friend try this and he had the same results! Give it a try and see what you all think!!!
-Ace