Cost for 2 40w Florecents.

[Shovelhandle]

just for a few examples,
48" 34 watt cool white T-8 lamps produce aprox 90 lumens/watt
48" 54 watt T-5 cool white lamps produce aprox 92 lumens/watt
CFLs from 42W to 200W produce an average of 64 lumens/watt
The best ($$$) HPSs will max at 150 lumens/watt while average 250 W HPSs will produce around 116 lu/w and the wee 35W HPSs get as low as 64 Lu/w

Shovelhandle