To the older posts for subzero, you don't really need to gather energy from other sources. It's sloppy and can pollute your energetic body. Subtle energy is all you need to know. Basically your intention, thinking and goal. Use your thoughts to generate energy instead of sucking energy from outside. Like when your're making a psi ball think of it forming or I'll go a little further, feel it forming or visualize. Your thoughts can generate so much power you don't even realize just focus, meditate and practice. Results will appear. Absorbing energy is a newbie trick which doesn't make you have a lot of going for you, but when you apply thought, one direct thought can create a ripple effect and continiuing that upon each other can create so much. Good luck.
...That was enlightening.
I did not know that. Thanks for the tip, even though it wasn't directed at me.