The air people breathe is free. But for some University students, cleaner air will come at a price.

Beginning in 2006, Xcel Energy will charge its customers 6 percent to 8 percent more for natural gas to convert two of its coal-burning plants to natural gas, a decision that could benefit the environment and public health.

The conversion is part of Mayor R.T. Rybak’s city environmental improvement plan announced Jan. 17. In December, Xcel Energy confirmed that it would convert its coal plant in northeast Minneapolis and another in St. Paul. The project will cost about $1 billion.

Ed Legge, a spokesman for the power company, said this means a maximum of an extra $3.50 per month for its average customer – 10 to 15 cents per day.

Rybak said the Riverside plant is the number one source of air pollution in Minneapolis and that converting the plant is an integral step toward improving water and air quality.

Public health will also improve, said Andrea Kiepe, organizing coordinator of Clean Water Action Alliance of Minnesota.

“We’re talking about serious health benefits,” Kiepe said. “Anything we can do to wean ourselves off of coal is a step in the right direction.”

School of Public Health professor Matt Simcik said the results of this conversion would be “huge,” as many chemicals coal-burning plants emit might affect pregnancies as well as people’s respiratory and neurological systems.

Sulfur dioxide, carbon dioxide and nitrogen oxides from the Riverside plant account for $57.4 million in health costs for Hennepin County, according to a 2002 study by Carl Nelson, community energy initiative project manager for the Minneapolis environmental organization Green Institute.

The reduction of dangerous emissions would decrease health problems by 90 percent, Nelson said.

Justin Eibenholzl, environmental coordinator for the Southeast Como Improvement Association, said he has heard complaints from several neighbors about the odors of the emissions. After looking at health statistics and hearing complaints, he worked with environmental groups and several neighborhood associations to initiate the change.

Even though the conversion will not be complete until 2009, Eibenholzl said he eagerly anticipates the change.

“We’re pleased with the decision, but we’re just waiting for action to be taken,” the energy coordinator said.

Some University students, however, disagree with the conversion plans, saying their budgets do not often allow for an extra few dollars in expenses each month.

Junior Natalie Tomhave said she does not favor the increase.

“For University students, that’s not the best idea,” she said.

Meanwhile, other students said they are willing to pay the additional charge.

Junior Ted Eckels said he will pay extra money for natural gas, adding that higher energy prices will help people become more energy efficient.

“As long as it helps the environment, it’s a good thing,” first-year student Tracy Canton said.