April 2008 • Renew Schools look to reduce carbon footprint by installing geothermal heating systems

Mt. Vernon High School in Fortville is currently under construction. “We are going through an expansion/renovation,” said Mike Horton, assistant superintendent of Mt. Vernon Community School Corporation.

This renovation is unique, though, because not only are they adding space, but the school will be reducing their carbon footprint in the process. “The building will be heated and cooled using geothermal energy through geothermal heat pumps,” said Horton.

Six years ago, the school corporation put a geothermal system in the junior high school, and according to Horton, it was an easy decision to decide to convert the high school to the same system.

“The cost effectiveness over time is great and it’s a pretty short payback period,” he said. “There is also less maintenance versus the old boilers and chillers.”

It wasn’t just about saving money, though. “Part of what we teach our kids each day is to respect the environment,” said Horton. “We’ve done a number of things in this area such as using our retention ponds or ‘green space’ for learning labs.”

So, what is geothermal energy and how does it work?

Geothermal energy is heat from within the earth. Above ground, temperatures can change constantly, but in the top 10 feet of the Earth’s surface, the temperature stays between 50 and 60 degrees Fahrenheit, meaning the ground temperature stays constant in many areas. This means that the temperature of the soil is usually warmer than the air above ground during the winter months and colder than the air above ground during the summer months.

With geothermal energy, the heat pumps use the Earth’s natural constant temperatures to heat and cool buildings by transferring heat from the ground into buildings or the reverse in the summer months.

According to Randy Stair, co-president of Stair Associates Inc., a mechanical/electrical engineering company in Indianapolis who is currently converting Mount Vernon High School’s system, the Earth’s natural heat is extracted from the ground through a continuous closed water loop through piping that goes into the ground, comes back out and runs through the building. (See diagram to the right.)

“We drill boreholes 200 to 300 feet in the ground,” said Stair. “We drop a piece of pipe with a U-bend, so the pipe goes in and then comes back out and circulates through the building. The same water goes through these loops and is heated by the Earth. That water travels to the heat pumps in the school where it then heats the classrooms in cold moths. In summer, the heat is taken out of the classrooms through these pipes and it cools the room.”

According to the U.S. Environmental Protection Agency (EPA), geothermal heat pumps are the most energy-efficient, environmentally clean and cost-effective systems for temperature control. Although most homes still use traditional furnaces and air conditioners, geothermal heat pumps are becoming more popular – even in schools.

Mt. Vernon isn’t the only school corporation moving to geothermal energy systems. According to Stair, his company has converted, or helped build, geothermal energy systems for at least 18 schools across Indiana.

“With this system, it’s not only great for the environment, but schools will see a 30 percent savings on their energy cost and a 10 to 20 percent savings on maintenance,” said Stair. “I really try to get schools to at least consider this option. It’s not as expensive, even up front, as what people have been led to believe. It’s affordable, saves money and is good for the environment.”

Other schools in Indiana using geothermal energy include (but are not limited to):

Franklin County Community School Corporation, Brookville

• Brookville Elementary School
• Brookville Middle School

South Madison Community School Corporation, Pendleton

• Maple Ridge Elementary School
• East Elementary School
• South Elementary School
• Pendleton Heights Middle School

Elwood Community School Corporation, Elwood

• Elwood High School
• Oakwood Elementary School
• Edgewood Elementary School

Mt. Vernon Community School Corporation, Fortville

• Mt. Vernon Middle School
• Mt. Comfort Elementary School
• Mt. Vernon High School

Clark-Pleasant Community School Corporation, Whiteland

• Whiteland Elementary School
• Clark Pleasant Middle School

Blue River Valley School Corporation, Mount Summit

• Blue River Valley High School

MSD Southwest Allen County, Fort Wayne

• Ernst Road Elementary School
• Covington Elementary School

Tippecanoe School Corporation, Lafayette

• James Cole Elementary School
  

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Is your school already participating in green activities? We want to know about it. Please contact Lynelle Miller at lamiller@doe.in.gov to pass on your innovative classroom and project ideas as well as share photos.