Beam Fire At Will got additional power drain because that was an attempt to balance it extreme damage boost. It did not help, actually.
Cannon Scatter Volley's increased energy drain was a bug and got fixed.
Attack Pattern Omega, Beta, Delta, High Yield Torpedo, Torpedo Scatter Volley, Mine Dispersal Patterns, Tactical Team, Cannon Rapid Fire, Cannon Scatter Volley - they all do not increase energy drain.
CRF and CSV does drain "more" it may be because it is firing faster but the drain is there. I notice the difference in drain between non CRF and CRF. Non CRF my power hardly dips below 115 on CRF I will dip to to 100. My weapon power is about 127