They said the move would save 279bn cubic feet of natural gas and save $4.4bn in energy bills by 2020.

 

"The change in the beginning of daylight saving time is just one step towards making our country more efficient in its usage of energy and conscious of our environment"

Edward Markey, Democrat representative

"The change in the beginning of daylight saving time is just one step towards making our country more efficient in its usage of energy and conscious of our environment," Markey said Wednesday.

 

Computer concerns

 

Critics of the early change say businesses have been slow in updating critical computer systems and fear it might lead to inaccurate times for business transactions and timetables.

 

"We fear that some high-risk organisations are not well prepared," said Andy Kyte, research vice president at the consulting firm Gartner Inc.

 

Kyte said that "it could generate business procedure and IT system problems that modestly disrupt smooth business operations, irritate customers and tarnish professional reputations."

 

However, Kyte said that the change was not on the same scale as Y2K, when electronic calendars in some computers and electrical appliances had to be re-calibrated to recognise the year 2000.

 

Others are concerned that the US workforce will struggle with one less hour of rest.

 

"Not only will this catch many Americans off guard in terms of their sleep habits, but information technology experts are predicting some computer glitches related to the early shift," said John Challenger of the consulting group Challenger, Gray and Christmas.

 

Daylight saving time did not become a national law in the US until 1918, when congress passed legislation creating it as a way to save energy by, in theory, moving an hour of "wasted" sunlight to the other end of the day, when people are awake.