In 2005, President George W. Bush signed into law a broad energy bill that will extend Daylight Savings Time by four weeks. The United States had previously observed DST from the first Sunday in April through the last Sunday in October, however under the new law DST begins in March and ends in November. The new period of DST went into effect in 2007, and continues again this year.

In 2008, Daylight Savings Time will begin on 2:00 a.m. March 9, which is this upcoming weekend. At this time, you will need to turn your clocks ahead one hour.

In other Daylight Savings Time related news, a new study out of Indiana shows that while conventional wisdom has claimed that DST saves on energy, that's simply not the case.

According to the Wall Street Journal, who first reported on the Indiana study, springing forward may actually waste energy rather than save it.

The study, which was conducted by the University of California-Santa Barbara economics professor Matthew Kotchen and Ph.D. student Laura Grant, looked at how extending daylight savings time across Indiana worked out. What they found was that it mostly had negative results:

• Residential electricity usage increased between 1 percent and 4 percent, amounting to $8.6 million a year.
• Social costs from increased emissions were estimated at between $1.6 million and $5.3 million per year.
• However, possible social benefits -- enhanced public health and safety and economic growth -- were not studied.

According to the study, an extra hour of daylight in the evenings might mean we spend less on electricity to power lights, but it means that houses are warmer in the summer and colder during the cooler months of DST. So overall, the reduced cost of lighting is offset by increased costs in air-conditioning on hot afternoons, and increased heating costs on cool mornings.