Indiana’s shift to daylight saving time has added millions of dollars in increased electricity and pollution costs, according to a study from a University of California-Santa Barbara professor.

The shift caused electricity demand to rise anywhere from 1 to 4 percent, due primarily to increased air conditioner and heating use, according to the study by economics professor Matthew J. Kotchen. That causes electricity bills for Indiana households to rise an estimated $8.6 million per year, and “social costs” of increased pollution emissions to increase up to $5.3 million.

The bill increase translates to an additional cost of $3.19 a year per household.

“The point of this study is just to shed light on the old myth that daylight saving time saves energy,” Kotchen said, noting that this argument has been made since Benjamin Franklin raised the issue more than 200 years ago.

Kotchen said daylight saving time reduces lighting costs, but the increase in both air conditioning and heating expenses offset that.

Indiana started mandating statewide observance of daylight savings time in April 2006. Most of the state had spent more than 30 years not observing the time change like 47 other states have done. Arizona and Hawaii do not observe daylight saving time.

This year, the switch to daylight saving time falls on March 9.

Gov. Mitch Daniels pushed for the change to daylight saving time. But spokeswoman Jane Jankowski said the governor never painted the change as being about energy consumption or savings to homeowners.

“The reason the governor supported daylight saving time was about jobs and removing a handicap from Indiana’s economy,” she said.

Kotchen’s study involved utility bill data from 240,000 homes in 24 southern Indiana counties served by Duke Energy. He used that information to devise cost estimates for the entire state.

Kotchen said he didn’t think the difference in climate between southern and northern Indiana was significant enough to skew results.

He also said the study looks only at residential electric bills, and there could be other variables that affect the cost to Indiana residents.

“I would not draw any conclusions from this as to whether you should keep or get rid of daylight saving time,” Kotchen said.