EPPING, N.H. — At Verdant Pastures’ Leddy Center for the Performing Arts theater here, a 20-ton geothermal system designed and installed by Intelligent Heat and Power, Stratham, N.H., creates a comfortable theater and office for patrons, actors and staff no matter what time of year while decreasing the theater’s heating and cooling costs — the system is expected to cut annual energy costs by up to 50%.
In 2008, Steve and Andrea Kaneb bought the historic 93-acre New England property that can be used for a variety of events, such as meetings, conferences and fundraisers. The theater was the first building to be renovated on the property because the HVAC system was deteriorated beyond repair.
"A geothermal heating and cooling system such as this one is an excellent choice for a commercial or private property," said Jeffrey Brideau, president of Intelligent Heat and Power. “They are extremely efficient over a huge range of temperatures, from sub-zero winter mornings to 100 degree summer days. In addition they can save up to 70% on heating and cooling bills while reducing the impact on our environment."
According to Brideau, the unique feature of this geothermal system is the horizontal ground connection since horizontal ground loops are rare in the New England area due to the rocky soil and thin overburden.
“Occasionally residential projects use horizontal loops if there is sufficient soil depth, but commercial properties are almost always vertical in this region,” explained Brideau. “The owner was fortunate in their site location. Likely due to being on the shore of the Lamprey River, there is a good amount of overburden on their plot. It would be hard to ask for better soil. At about five feet we hit clay, and above that is sand.
“With a loop field location at the bottom of a gradual hill we also have a continuous flow of ground water even in the dry month of August,” added Brideau. “This raises thermal conductivity of the soil tremendously and the flow of water will keep ground temperature from swinging as dramatically as it normally would.”
The custom staging, zoning and priority controls were designed and built by Intelligent Heat and Power. To design the system it took Intelligent Heat and Power a total of two to three weeks spread out over several months, and three months to complete installation of the system.
The geothermal system consists of four Florida Heat Pump EV split section units and four Unico air handlers. Two air handlers are dedicated to the theater’s seating area and are connected to Imperial energy recovery ventilators. Theses ventilators only bring in fresh air when CO2 levels in the theater exceed a threshold level, thus, reducing heating and cooling energy. The other two air handlers serve offices and the stage area as independent zones unless there is a need to divert air from the second set of air handlers to the theater seating area. The high velocity duct system allowed the duct work to be placed in the narrow catwalks above the theater.
“Our system was intended to work in conjunction with a brand new Viessmann boiler that had been installed to heat the radiant slab of the theater,” explained Brideau. “During the winter months, an error on the part of someone servicing the boiler caused the boiler to become inactive for most of December and January. During that time, the geothermal system was able to heat the building without any issues even though it was not designed to carry the entire load. As such, it should be expected that the savings were significantly in excess of the estimated $5,000.”
The theater was bought by the Kanebs at foreclosure, and before they renovated it, it was in disrepair for many years, so there is no data on past operational costs, however, according to Brideau, it was projected by his company that the geothermal system could provide a cost savings of approximately $5,000 per year in unused oil.
“Geothermal HVAC systems are equally efficient at cooling as for heating,” said Brideau. “By installing a geothermal system instead of a basic air-source cooling system, we were able to offset a substantial portion of the oil heating costs for the building as well as serve the comfort and ventilation needs in the cooling season.”
“While more than 200 patrons enjoy the indoor climate of the auditorium, they can also feel good knowing that the heating and cooling is friendly to our global environment,” said Steve Kaneb. “A geothermal system makes long-term economic sense and helps roll out part of our vision for Verdant Pastures.”
The Kanebs plan to continue renovating additional facilities and further develop the property at Verdant Pastures.