JARED SOARES The Roanoke Times

Installation of a geothermal heating and cooling system at Mount Pleasant Elementary in Roanoke County has turned the baseball field into a work zone.

Pipes stand at attention in left field. A drill rig is parked atop the pitcher's mound.

The baseball field at Mount Pleasant Elementary School is out of commission while 123 wells are drilled to make way for a geothermal system to heat and cool the school.

The heavy machinery will be gone by spring and the field will be back to normal for little sluggers -- and the school will be one of four Roanoke County public schools using geothermal energy to heat or cool water in underground pipe networks.

Marty Misicko, the school system's director of operations, said the HVAC systems, which cost between $750,000 and $1 million, pay for themselves in about five years because they are highly efficient, replace the need for boilers or chillers and do not rely on fossil fuels.

"There is a little bit more of an upfront cost," Misicko said. "But if you think of the building[s] being here for the next 50 years, it is an incredible savings."

Northside High School was the first Roanoke County school to switch to a geothermal system when it was renovated about two years ago. Now three elementary schools -- Cave Spring, Green Valley and Mount Pleasant -- are getting the systems through a $32.2 million renovation project at the three schools and another high school. A fifth system is planned for the new Mason's Cove Elementary School, where construction is slated to begin in the spring.

Geothermal power utilizes the near constant temperature of the earth's subsurface, which is about 54 degrees, instead of using boilers to heat large volumes of very cold water by burning fossil fuels. Geothermal power essentially preheats the water so heat pumps can efficiently heat it to the desired thermostat temperature.

School board member Jerry Canada, who represents the Hollins District, said he is a geothermal proponent.

"The payback is phenomenal," he said.

Natural gas consumption at Northside High has decreased by about 90 percent since changing to geothermal. Now all Canada said he has to hear is the soil is suitable for geothermal and he is sold on installing it.

"There's no question with that kind of return," he said.

The benefit of the long-term savings over the initial expenses is something one Virginia Tech construction professor said finally is getting noticed.

"Public-sector owners are finally beginning to consider life cycle costs, not just first costs, in making investment decisions," Annie Pearce of the college's Myers-Lawson School of Construction wrote in an e-mail.

John Reynolds, superintendent of Rockbridge County Schools, said three elementary schools there have been renovated to include geothermal systems.

"Whenever we could, we would use it again," he said. "Our experiences with it have been nothing but good."

Reynolds said the division expected each system to take about three years to realize enough savings to pay for itself. But in most cases it only took half the time -- about 18 months.

"In the past, it [installing geothermal] was cost prohibitive," Misicko said.

But rising utility costs and improvements in technology have made it feasible, he said. And the school division has another edge: Construction costs are lower than expected because of the economic recession.

Bids for the three elementary schools and William Byrd High School renovations, which were awarded last summer in a combined bid package, came in 23 percent under budget, said Penny Hodge, the school system's assistant superintendent of finance. That will allow the school board to pursue a fourth elementary school renovation (at Mason's Cove Elementary) with the savings. Mason's Cove Elementary is isolated in the mountainous northwestern area of the county that is not served by natural gas; currently it is heated by burning coal.

"Our only options were propane or electricity," Canada said. "Neither one of those is a great option when it comes to expense."