Daylight Savings Time Could Be Costing Billions Yearly in Electricity

"The culprit is most likely a tradeoff between the reduced demand for lighting and an increased demand for heating and cooling—and it’s a trade that DST is on the losing end of."

http://www.treehugger.com/files/2008/11/daylight-savings-time-costing-billions-dollars-year-electric-bills.php