I'm using 6ea 100watt output
cfl's in the 6500k spectrum.
6 x 100 = 600watts of light.
These
bulbs use 23 watts ea.
23x6= 138 watts.
138watts ./. 120 volts= 1.15 amps.
Same for flowering except bulbs are 2700k.
my utility bill for October was $58.60.
As far as penetration, the blubs are in clamp on shop light fixtures and I can move them where needed and my plants are doing great.
This may not work for everybody but for a $58.60 utility bill, it works for me.