John Jay students walked up to the field at the top of the hill behind the Katonah Elementary, where three rigs and several trucks were parked. Loud releases of steam punctuated the steady rumble of engines. Already-dug geothermal wells were scattered about the school’s athletic field – each one surprisingly narrow, about the size of a tree protector tube.
This was AP Physics field trip to Katonah Elementary School, where crews are actively drilling wells for the school’s new geothermal heating and cooling system. The trip supported student’s understanding of thermodynamics, heat transfer and the conversion of energy between different forms.
The tour was hosted by some of the most knowledgeable people about the project: Richard Markgraf, architect and associate with KG+D Architects; engineers Laurence Barile and Paul Gallagher, principals with Barile Gallagher Associates; and Mike Lavoie, Katonah-Lewisboro Schools’ director of facilities.
Teachers Jim Panzer and Daniel Longhurst gathered the students in front of the school to talk about the big picture.
Architect Markgraf reminded the students that the geothermal conversion was one of several upgrades the school has had since it was built by President Roosevelt’s Public Works Administration in 1939. “It was first heated with steam,” he said. “The windows were the AC.”
About fifteen years ago, KG+D Architects was part of the team that converted the steam to gas. That system will remain as backup for the more efficient geothermal system.
The brick walls of the school are 32 inches thick, the students learned. The walls’ high thermal mass was one of the reasons the school was a good candidate for geothermal.
Engineer Barile described the process of determining how many geothermal wells the school would need for heating and cooling. “We dug a 500-foot-deep test well to determine the energy potential of the site,” he said. “We got lucky. We hit granite. Heat likes to go through that quickly.”
At the top of the hill, at the athletic field/geothermal field, a well driller came off the rig to speak to the students. “This site is eighty 500 footers,” he said. “That’s a lot of hole to cut!” He said that the rock was so hard that the rigs needed to replace their drill tips every 300 feet!
The tour ended in the basement of Katonah Elementary, where the geothermal loops will enter the building, and be monitored and controlled.
Lavoie highlighted the importance of students seeing real-world applications of a sustainable design.
“Visiting a geothermal well field, learning about a cutting-edge HVAC system and meeting the people who make them possible, our students learned of the opportunities as future engineers, architects, builders, tradespeople and sustainability-minded leaders,” said Lavoie. “We’re deeply grateful to the engineers, architects and well drillers who took the time to share their expertise with our students.”