From a previous U.S. News article about 13 Facts about Daylight Saving Time:
"Daylight saving time was first used during World War I, as part of an effort in the United States and other warring countries to conserve fuel. In theory, using daylight more efficiently saves fuel and energy because it reduces the nation's need for artificial light."
This fact has long been disputed by politicians and energy experts. Many believe that the extra artificial light needed in dark Daylight Savings mornings cancels out the benefit of brighter evenings. However, a 2008 Department of Energy report to Congress found that Daylight Savings Time does indeed save energy, though not as much as we'd hoped. According to the report, the total energy savings throughout the period of Daylight Saving Time add up to 17 Trillion Btu of primary energy consumption, which is only .02 percent of the country's total use in 2007.
To put that number in perspective, the average household uses 106 million Btu per year. So, the energy savings throughout the period of daylight savings would be roughly equivalent to that of merely 160,000-some households, which is about the population of Vancouver, Wash.
This will be the second year that we adjust for Daylight Savings in March, not April, so don't forget: Sunday is the day to "spring ahead."