if you are already on a 15 amp breaker
1 600 watt of flower
1 200 watts of veg
1 300 watts of fans and extra components for exhaust and ventilation

around 1100 watts of power
15 amp breaker is good for about 1800 watts and 80% of its power is good for about 1400 watts of power(dont want to exceed over 80% power much)

no electrition needed unless you want more hid lighting