This is in reply to Jberry's concern regarding power costs.
Yes a lot of power companies (like PG&E in northern California) calculate their "residential" charges in relation to a low "baseline" usage level and, if you use over the baseline, the charges per KWH triple or quadruple (sp?) .
However, if you elect a "commercial" rate you can choose a night time rate of $0.11 for as much power as you want. (My rate was as high as $0.40 per...about $1,600/month).
How do you get a commercial rate ? I moved my grow to a warehouse space and was able to triple my lights for the same cost as I was paying.
I never asked PG&E if I could get the commercial night time rate for a residence. (Didn't want to red flag that I was using a lot of power) but maybe you can who knows ???
Anyway, thanks for reading. Good luck on everyone's endeavors.