Beginning in August many state offices will be closed Fridays to cut energy costs, shifting thousands of state workers to a four-day workweek, 10 hours a day.

Gov. Jon Huntsman Jr. said his new "Working 4 Utah" initiative, which he announced Thursday, is also intended to provide better customer service to Utahns because the agencies affected will be open longer hours from Monday through Thursday: 7 a.m. to 6 p.m.

"This will be a very good thing for the state," the governor told reporters during the taping of his monthly news conference on KUED Channel 7, where he unveiled the new program set to take effect Aug. 4.

It is expected to save taxpayers an estimated $3 million in energy costs as well as cut the amount of money state employees have to spend on gas to commute to work. Huntsman said the program will help the environment by reducing the state's carbon footprint.

The schedule only affects executive branch agencies, not state courts or the Legislature. Also excluded is public and higher education. Higher-education buildings make up the majority of the state's 3,000 buildings.

And the governor said other state functions will be exempted from the new schedule, including some in corrections, transportation and human services. But, he said, as many as 1,000 buildings throughout the state could end up being shut down on Fridays.

Many details remain to be worked out between now and August, however.

For example, the Department of Health still needs to determine whether to keep open the Bureau of Vital Statistics on Friday so people can pick up copies of birth and death certificates.

"We'll figure out where we can shut down on Friday," said Tom Hudachko, health department spokesman. He said that's tricky because many department services, such as the medical examiner's office, must be available around the clock.

The projected energy savings are based on an analysis of six state buildings, including the massive office tower behind the state Capitol, according to Kim Hood, head of the Department of Administrative Services.

Hood said shutting down just those six buildings an extra day every week over the next year should shave $123,000 from the state's energy bills. It should also save employees in those buildings nearly $313,000 in gas costs.

About 23,000 state workers will be affected by the change and Huntsman predicted about 10 percent will have difficulties making child-care, transportation and other arrangements needed to accommodate the change from working five, eight-hour days a week.

Many local governments in Utah already have four-day workweeks.