The first part of her passive heals her according to power bars spent by his opponent (it would use the actual amount spent, after being modified by e.g. Doctor Fate's passive). Enhanced block abilities do not heal her.
Energized Starfire's super will heal her team (but not herself) for 5%-20% of their maximum health, and the amount is not affected by the combo counter.
Previously, the same heal is applied upon using her other specials, but this has since been removed.