You can do the following:
Maxed out A rated PD, charge enhanced + fast charge experimental
Two large, Two medium, two small, beam turrets, G5 max efficient
Three pips to weapons allow for endless fire and around 48% heat with a maxed A rated G2 monstered power plant.
If you mod the PD towards weapon charge you can probably go for efficient G5 beams all the way with 4 pips.
Additional huge and large still may consume too much power.
If you want only one additionsl large it should work, too. But you will need 3.5 to 4 pips on a reular fast charge PD
Heat won't be an issue at all.
I can have 6 turrets fire + a large and huge long range PA which can fire three times before over heating, plus very fast heat ventilation.
Thermal conduit is very good though.
Edit: My Setup
Maxed G5 A rated PD, charge focused + experimental
Maxed G2 A rated PP, monstered
6 beam turrets maxed G5 efficient, thermal conduit
2 G5 maxed long range PA, thermal conduit
Three wep pips for endless fire but hardly energy gain.
4 pips necessary to charge the capacitor back up if you stay on target very well. If not three pips will do in most cases, depending on PA usage.
Hear only rises when PA gets fired but declines below 50% quickly enough unless you do multiple shots in a row.