Compact Fluorescent (CFL) Grow Lights
Compact fluorescent lamps (CFL) deliver more lumen output and consume less wattage than incandescent bulbs. They also run much cooler.
If you are only vegging and your garden is small, CFL bulbs can be a great option. But for a larger garden or for flowering, they aren't powerful enough to be the main lighting source. They make excellent supplemental lighting, however, to fill in those shadow zones.