Green PSU
From MTUGreenComputing
80 Plus Program
The 80 Plus Program for power-supply manufacturers. If the PSU is certified it will throttle back it's power output so that it only outputs the power that is needed for the machine to run at a given load. An 80 Plus Power supply can save about 85 kilowatt-hours per year.
References
1. http://www.extremetech.com/article2/0,2845,2099781,00.asp
