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.

A recent study of global emissions revealed Australians to be the world's worst polluters per capita, producing up to five times as much Carbon Dioxide (CO2) from generating power as China. Coming in second was the United States, with eight tonnes of greenhouse gas per head, which is 16 times more than that which is produced by India. The United States was also found to have produced the most CO2 in total, followed in second by China.

The data was compiled by the Center for Global Development, a U.S.-based organization, based on data presented on the Carbon Monitoring for Action (Carma) website. Carma's site is believed to be the first global inventory of emissions, which looks at 50,000 power stations worldwide.

One of the interesting things that Carma points out is that although U.S. power plants emit the most CO2 (2.5bn tonnes per year), Australian power stations are the least efficient on a per capita basis at 10 tonnes, compared with the U.S. per capita emissions of 8.2 tonnes.

China's emits the second highest total amount of CO2 in the world's power sector, putting 2.4bn tonnes of CO2 in the atmosphere annually. However, China's emmissions are far mroe efficient than Australia's, and are only one-fifth of Australia's on a per capita basis.