For my 1000 watter I have a 40 amp breaker dedicated to lighting.. You could run 2 fans and 1-1000 watter saftley and keep you from any worry! Both my 600's and 1000 watters are electronic ballasts,so that would make a difference in amp draw and running amps as well..Hope this was some help!

Ga Grown!
GaGrown Reviewed by GaGrown on . Just starting--power requirements I'm using an insulated 8 x 10 shed with a large roof fan. I'm going with 2 systems, either 600w or 1000w HPS, haven't decided yet. Will need heat in the winter. How much power do I need? I was thinking 20 amps, but someone told me that with HPS I need more. Rating: 5