The amber accent lights along the Mackinac Bridge cables are now turned off at 1 a.m. as part of a plan to reduce energy consumption by 11%. Turning off the decorative lights early will save about $2,000 annually, and other steps will save $13,000, said Bob Sweeney, executive secretary of the Mackinac Bridge Authority.

The other measures include powering down computers at night and on weekends, using motion detecting lights in areas of the storage buildings, installing programmable thermostats, and replacing canopy lights at the toll plaza with lightemitting diode (LED) lighting. The largest savings will be seen by turning off half the large lights used at the toll plaza. That, alone, said Mr. Sweeney, will save $5,200 annually.

All state agencies are required by December to reduce energy use by 10% annually under a directive issued by Governor Jennifer Granholm last November, called the "green initiative."