Shifting an hour of daylight from morning to evening for an additional four weeks each year is expected to cut fuel consumption, as demand falls for electricity during early-evening peak hours.

Sports teams will be able to start their seasons earlier, as well as backyard barbecue enthusiasts, while some in law enforcement think evening crime rates could fall. Orthodox Jews, who wait until sunrise to say morning prayers, lobbied against the provision and airliners complained it would throw their international schedules further out of sync with Europe, costing the industry millions of dollars.

The energy savings are expected to translate into a 10.8 million-metric-ton reduction in carbon emissions over the next 13 years, according to an analysis by the American Council for an EnergyEfficient Economy.