U.S. Energy Information Administration - EIA - Independent Statistics and Analysis
5.4 Efficiency Have you ever noticed how hot an incandescent light bulb gets after it has been left on for a while? An incandescent bulb transforms only. - ppt video online download
Watts The Deal? Demystifying LEDs, CFLs, Halogens And More : NPR
LED vs. regular lightbulbs: Do they really make a difference?