Daylight saving time 2011 begins Sunday, March 13. It will be the fifth year since Congress changed daylight saving time in the U.S. from the first Sunday in April to the second Sunday in March. The change was mandated by the Energy Policy Act of 2005, but extending daylight saving time has not proven to save energy.
Daylight saving time: winners and losers
Daylight saving time 2011 moves clocks forward one hour at 2 a.m. on March 13 everywhere in the U.S. except Arizona and Hawaii. Saving energy has been the rationale for daylight saving time since it was first implemented by Germany in World War I to save coal. In theory, extending daylight hours with daylight saving time saves energy by reducing the need for electric lighting. However, it has been argued that manipulating clocks to save energy is the equivalent of extending the length of a rope by cutting off one end and attaching it to the other. Daylight saving time is controversial because it benefits industries in retail and outdoor recreation, yet causes difficulties for such industries as farming and entertainment.
Energy saving benefits called into question
To promote energy savings, a provision in the Energy Policy Act of 2005 extended the period of daylight saving time by four weeks. The change amended the Uniform Time Act of 1966, and the earlier “spring forward” time was first enacted on March 11, 2007. Authors of the Energy Policy Act of 2005 claimed that extending daylight saving time would add up to a total energy savings in the U.S. of up to 1 percent. However, a study in Indiana after that state put all counties on daylight saving time in 2006 found a net decrease in energy savings. Converting the entire state to daylight saving time cost Indiana households an extra $8.6 million in utility bills due to higher heating costs in the morning and and higher air conditioning costs in the afternoon.
Daylight saving time pros and cons
Daylight saving time hasn’t been proven to save energy, but research has noted an increase of heart attacks during the first week of daylight saving time, attributed to sleep deprivation. On the positive side, research has found that daylight saving time reduces fatal car crashes and vehicle collisions with pedestrians.