Geothermal applications make the grade for two Northeast schools
Head of the class.
Talk about making the grade.
Two educational facilities in the Northeast dug deep and selected geothermal applications to provide heating and cooling for their campuses.
In Trenton, N.J., the year-round Christina Seix Academy opened its doors in the fall of 2012 serving children living with a lone adult caregiver. Seix Academy is a pre-kindergarten through 8th grade school that has eight buildings — including educational, residential and commercial facilities — spread across its 64-acre campus.
Haddon Heights, N.J.-based mechanical engineering and design firm Pennoni Associates created the system schematics at Seix Academy. The company submitted three options during the bid-and-award process, including standing column-well, dual-loop and closed-loop systems.
Pennoni’s MEP Division Manager and Project Engineer Bob Mellohusky created three separate reports on each type of system for the school. Mellohusky interviewed other owners of commercial properties that featured these systems and asked about maintenance and operation.
“We determined that a closed-loop, vertical-bore geothermal system was most efficient,” he says. “That would be the backbone of the HVAC for the commercial buildings, in addition to accounting for the future needs of the residential facilities.”
Originally, Mellohusky recommended the dual-loop system, but the owner had some reservations and selected the closed-loop system.
“The dual-loop system may have saved 40% on the drilling,” he notes. “In the end, we presented the facts and they made the decision.”
The application has five individual borehole fields with 106 boreholes (drilled at 350 ft.) and a 196-ton total capacity. Seix Academy wanted to include within the original design enough borefields and capacity for future buildings in case of an expansion.
When Mellohusky started value engineering the project, he switched the design to fit Seix Academy’s needs.
“We discovered that we needed to make adjustments to the borehole field design,” he says. “Originally, there was a centralized system borehole field for commercial and residential buildings. After review, we decided to use the same principle and the same equipment, but with a decentralized system.”
The decision to decentralize the system was made early in the process and subtracted a significant amount from the price tag.
“We were able to make that recommendation right off the bat. It was real easy to take a step back into that design concept and the owner bought into it right away as a cost-saving option,” Mellohusky adds. “They were able to knock about $500,000 off the budget and still have a geothermal system to sufficiently service the facility.”
Seix Academy’s application features ClimateMaster water-source and geothermal heat pumps. There are 68 Tranquility 20 Single-Stage Series horizontal and vertical units, five Tranquility Rooftop Series units and two vertical Tranquility 20 Single-Stage Series units.
As of press time, the Seix Academy is still in the process of seeking LEED Gold certification from the http://www.usgbc.org/ U.S. Green Building Council. Pennoni and Mellohusky added low-flow plumbing fixtures throughout the buildings — which include a 28,000-sq.-ft. academic building, a 13,900-sq.-ft. fieldhouse/gymnasium, a 10,440-sq.-ft. community resource welcome center and 7,180 sq. ft. of commercial space.
On the residential side of Seix Academy, there is 10,660-sq.-ft. dedicated to faculty residences, a 2,860-sq.-ft. headmaster residence and 10,970 sq. ft. of student dormitories.
For Mellohusky and his team at Pennoni, this was the first application they designed for a campus environment.
“Normally, it has been one building, one borefield,” he says. “This geothermal system needed a primary and a secondary loop. They are two independent loops, but the primary loop just handles the borefield while the secondary was put into each of the buildings. That was a wrinkle for us. That was primarily a cost- and energy-savings feature.”
The Seix Academy buildings were constructed to meet or exceed ASHRAE energy efficiency standards while achieving LEED requirements. The campus has its own photovoltaic solar array that was designed by Pennoni.
“They felt owning and operating their own solar array was the way to go,” Mellohusky says. “Our electrical group worked on that design and the integration into the grid. It’s not able to power the whole facility, but it is able to offset some of the costs.”
According to its website, the vision of the Seix Academy is to: “Provide young children living with a single adult caregiver, beset by acute economic needs, a strong education, critical core values and a safe environment, enabling them to become future leaders in their communities and beyond.”
Christina Seix, a successful businesswoman, has been a resident of New Jersey since 2004 and grew up with her mother with limited resources. She became the Chairman and CEO of New York City-based investment firm MacKay-Shields and then she founded Seix Investment Advisors. Her New Jersey-based company grew to become a leading investment manager in the industry. She sold her company in 2004 and used the money to create the Seix Academy.
Mellohusky says his team was very aware of the importance of this particular project based on that vision.
“My team felt good about working on this project,” he says. “They were cognizant of the gesture Christina Seix was doing. As we were working on it, there was a sense of pride we had for what the school was going to be.”
In 2012, East Stroudsburg University, located 46 miles north of Allentown, Pa., officially opened its $74 million campus student-housing expansion. The project provides students comfort and privacy in modern suite-style living with the latest in sustainable building practices.
The new sprawl has two residence halls with 960 beds, the 157,000-sq.-ft. Hemlock Suites and 173,000-sq.-ft. Hawthorn Suites. Within those two residence halls is some commercial space, including a 15,000-sq.-ft. fitness center (located inside Hawthorn) and university police offices (located inside Hemlock).
The central aspect of the sustainable building is a geothermal system that provides building tenants and occupants in-room climate control among other major benefits. The system was designed by Philadelphia-based mechanical engineering firm Wick Fisher White and MEP engineer for the ESU project, Dan Jewell.
Jewell worked with Philadelphia construction company P. Agnes on project. The design follows a similar concept used at West Chester University, a fellow Pennsylvania higher-learning institute. Jewell reports nearly 600 small-tonnage water-source heat pumps from ClimateMaster were installed for the project.
“Each dorm room was provided its own dedicated water-source heat pump,” he says. “The surrounding support spaces also were served by small-tonnage dedicated units.”
Each of the suites is enhanced with ClimateMaster’s Tranquility Vertical Stack Series heat pumps. Jewell and East Stroudsburg University selected the Tranquility units because of the energy savings, low maintenance costs, improved air quality and the reduction of ESU’s overall carbon footprint.
The Hemlock building has a 405-ton heat pump system and a 120-borehole field while Hawthorn has a 377-ton heat pump system with a 110-borehole field. The boreholes are 500 ft. deep and between the two buildings there are 526 Tranquility Vertical Stack and Tranquility 30 Two-Stage Series heat pumps. They range from 0.75 to 2.5 tons in capacity with the environmentally friendly EarthPure HFC-410A Refrigerant technology. ESU’s geothermal system uses the earth as its heat sink, which eliminates the need for a major piece of equipment such as a cooling tower or closed-circuit cooler.
“This reduced the amount of energy required to operate the system and reduces the amount of equipment that requires maintenance and repair,” Jewell says.
ESU Facilities Management Auxiliary Project Manager Thomas Bartek stresses how installing a geothermal system was the right fit for the university.
“We wanted these buildings to be as carbon-neutral as possible,” he says. “Our students have come to expect more privacy, more comforts and more conveniences in their residence life experiences. That’s what we’re giving them with Hemlock Suites and Hawthorn Suites.”
Each of the buildings, particularly in the commercial areas, has varied levels of accommodations at given times of the day. Jewell and Wick Fisher White designed the system around this aspect.
“We included a dedicated condenser water loop to maintain the buildings’ indoor conditions for the spaces that are anticipated to operate year-round, without having to energize the larger system components,” Jewell says.
Hemlock and Hawthorn were built concurrently and only 300 ft. apart. On top of that, there was an existing underground utility and storm-water management system in place when construction started. Those were redesigned to make room for the needs at Hemlock, throwing a wrinkle into Jewell’s plan.
“The greatest challenge was the limited space to run ductwork, piping and other utilities,” he says. “The floor-to-floor heights were low and we were required to coordinate duct runs and various structural framing members and floor joists.”
The new facilities were installed with high-efficiency fixtures to qualify for LEED credits.
“The plumbing was designed following the International Plumbing Code,” Jewell says. “We utilized low-consumption Kohler fixtures, allowing the project to achieve the credit for water-use reduction in excess of 20%.”
For these two educational facilities, geothermal heating-and-cooling systems provided all the above in terms of design flexibility, energy efficiency and cost savings.