The U.S. Department of Energy has named the ASHRAE/IES 90.1-2013 energy standard as the new national energy reference standard, superseding the 2010 version in effect until then.
Within two years, all states must put into effect a commercial building energy code at least as stringent as the 2013 version of 90.1, or justify why they cannot comply.
The updated standard pays particular attention to lighting controls, with more stringent requirements, including*: