You can't empower anything without raising energy.
What you probably mean and WiseDragon replied to is to rise your energies before power meditations/rituals. Yes this is advised, because it can get "dangerous" or have some side effect if you use up your soul's resources, so it is advised to rise your energies. But it can get as simple as breathing exercises or the 666meditation. "Yoga" can also do that.
This is especially important if you are dancing on the limit of what you can take.
And yes, logically the meditation will be more effective.