The chance for instant power plant detonation is rather low. I used to think that maybe it just needed a certain amount of damage done past 0% but after firing 3-4 huge plasma bolts directly at a 0% powerplant from 250m with no explosion I've come to the conclusion that each time the PP is hit is essentially a roll of the dice to see if it will destruct. Therefore it's always best to use high rate of fire weapons like pulse lasers to seal the deal! That being said... using large pulse vs medium pulse seems to kill quicker, so maybe there is some damage/armor penetration based factor in play.
Mr. Owl, how many licks does it take to destruct a powerplant? A 1... a 2... ah 3! The world may never know.
