Alternative system cuts energy costs, emissions

Medford - Underneath the playground at Kirby's Mill Elementary School lies something un­expected: about 100 pipes filled with a water-based fluid extending 500 feet into the ground where the temperature stays about 60 degrees.  The ground warms the water as it's pushed into the school where the heat is taken out. A pump blows the heat throughout the building. The reverse happens on a hot day. The system removes heat from the school, cools it in the ground and brings it back into the building.

    Known as a geothermal heat pump, it acts similarly to an ordinary heat pump, but uses the earth's natural heating and cooling properties instead of outside air. The Medford School District has three schools — Kirby's Mill, Taunton Forge and Chairville — with geothermal systems. Construction started last month on a fourth, at Cranberry Pines Elementary School, said Bryan McGar, assistant superintendent for finance and support services. The system, introduced into homes in the early 1980s, is making its way into schools and commercial buildings nationwide.  Compared to traditional heating and air conditioning, the geothermal system saves an average of 30 percent in energy costs and reduces greenhouse emissions into the atmosphere.

        About 40 schools in New Jersey run on a geothermal system, and in the next two years, the number is expected to grow to more than 100, said Lynn Stiles, professor of physics at Richard Stockton College of New Jersey in Pomona.  Schools in the tri-county area with the system include Gloucester County College in Deptford and Berlin Township's Dwight D. Eisenhower Middle School and John F. Kennedy Elementary School. "It's more efficient and cost-effective," said Brian Betze, superintendent of Berlin Township School District.  In addition, with installation costs dropping and the availability of rebates through state programs, the up front costs of a geothermal system are comparable to those of a regular system, Stiles said.

   The Kirby's Mill system cost about $2 million to install. Medford, though, received a one-time rebate of $300,000 through a state program. Also, a grant from the state School Construction Corp. covered 40 percent of the installation for the Kirby's Mill and Chairville schools, making installation comparable to that of a traditional system, said Joseph DelRossi, the superintendent.  Most of these schools use what's known as the closed-loop version of the geothermal system in which the water stays enclosed in the piping system Open-loop systems, which are less commonly used, function similarly, but cool and heat water that's pulled deep from the ground.

   Stockton College installed its system in 1994, the first institution in the world to use the closed loop system on a large scale, Stales said. Stiles said Stockton 's success led to the system's use at more schools and commercial buildings. He said visitors from China , Japan and European countries have visited Stockton to examine how the system cooled and heated most buildings on campus. "It's happening so fast because word has gotten out" Stiles said.

Niche Product.

  Even so, geothermal systems remain largely a niche product compared to traditional heating and air conditioning systems, said Glenn Hourahan, vice president of research and technology for Air Conditioning Contractors of America. The Arlington, Va. based trade group represents heating, ventilation, air conditioning and refrigeration contracting businesses. Hourahan said people choose traditional systems because they have lower up-front costs and are perceived to have lower maintenance and repair costs.

   Schools, businesses and homeowners should at least consider the geothermal system because of its lower operating costs, he said. "If the payback is quick, it doesn't matter if the up-front cost is high," he said. However, it is essential the system maintains a balance of heat in and heat out, Hourahan said. Without it, the ground temperature could drop or rise a few degrees, affecting the system's performance. A site analysis can determine whether this problem could occur, Hourahan said.

   Elsewhere in New Jersey , a handful of school districts are using geothermal systems. Jackson School District in Ocean County uses it in six schools, Pleasantville School District in Atlantic County in four schools and Middleton School District in Monmouth County in four, said Michael Fischette, principal of Concord Engineering Group in Voorhees. The company started installing the systems in schools in 1992 and has worked on more than half of the projects in the state. The company has 20 more schools in the design phase, said Fischette.  "The system, over the life of a school, is the most efficient to operate," he said, "I see it as the perfect solution to where natural gas is not available."

   That was the case the Medford School District faced in the mid-1990s. With no natural gas line near Taunton Forge Elementary officials decided to go geothermal McGar said. The favorable results led to its use at Kirby's Mill and Chairville schools, which both opened in the fall of  2004. Energy costs decreased by 9 percent with the new heating and cooling system compared with the old, which only had heating, said Joe Hilda Jr., the district's director of operations and technology. He uses a Web­based program to cool and heat individual rooms. "It takes advantage of what Mother Nature gives us," said McGair of the Medford School District