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ASAP

Single Voltage External Power Supplies

Last Updated: October 2007
See the federal standards main page to view current status

External power supplies are the small black boxes attached to the chord of many small or portable electronic appliances that convert AC supply voltage to lower AC or DC voltages on which the products operate. A typical power supply is only 25 to 60% efficient with several watts of standby power. A simple switch from magnetic to electronic components can increase this efficiency to 90%. California developed the first efficiency standard for power supplies that became effective in 2006, and several other states followed suit with laws in place by 2007 or 2008. In 2005 Congress directed the federal government to establish a rulemaking for external power supplies.

• Federal Documentation (DOE Web site)

Update
In December 2007, the Congress enacted H.R. 6, setting an initial minimum efficiency standard for external power supplies.  This standard allows for no more than one-half watt in “no load” mode and a minimum active mode efficiency that varies by output.  The new standards are effective July 1st, 2008.  The Department of Energy must, by July 2009, determine, if standards should be applied to additional types of power supplies excluded from the legislated standards.  By July 1st 2011, DOE must conclude a rulemaking which would set new standard for power supplies not previously regulated and would update the standards legislated in 2007.  Such new and revised standards would be effective July 1st, 2013.  A second round of review and potential increases is due by July 1st, 2015 and would be effective July 1st, 2017. (February 2008)