FGCU’s geothermal air conditioner reduces impact on the environment

By Jaryd Brady

Florida Gulf Coast University markets itself as a “sustainable campus,” from native plants to reduce maintenance to Leadership in Energy and Environmental Design certified academic buildings. FGCU’s green initiatives include its method for cooling academic buildings. Through its cooling plant, FGCU not only reduces costs financially, but also environmentally.

FGCU’s physical plant, when it was built in 1996, was connected to the original seven buildings in operation through a central plant with an ice cooling system, 800 tons of cooling and two chillers.

“It’s really a simple system when you look at it,” Jim Hehl, the director of the physical plant at FGCU, said. “We distribute the ice via pumps underneath the academic buildings that are connected to the plant.”

FGCU’s energy storage tanks work directly with chillers to produce and store ice at the physical plant. At night, the water is mixed with glycol and circulated through the chiller in the energy storage tank to produce ice. The following day, during hours of operation, the ice is melted and the glycol is pumped out through FGCU’s plate frame heat exchanger. The chilled water is then circulated through underground pipes to cool the campus.

The cooling plant at FGCU serves as the primary air-conditioning unit for multiple buildings, as opposed to having one A/C unit for one building operating at all hours of the day. The plant operates Monday through Friday and cools the buildings with traditional air-condition on the weekends, which not only reduces the impact on the surrounding environment, but saves the university money that would be going towards power bills.

“Whenever we don’t run our chillers during those periods we keep our light bill very low as opposed to what it would be.” Hehl said. “We not only save on the monthly FPL bill, but we also, by agreeing to this time-use rate, get a large rebate check of over half a million dollars from FPL.”

The physical plant at FGCU also saves money on sewage because all the water used outside of storage is evaporated. 

“It’s impactful,” said Brenda Thomas, program director for Colloquium, a course that educates students on sustainability. “The university is growing, but we have to balance the needs of our students.”

FGCU continues to expand, not only in the case of students, but also building and operations wise as well. FGCU currently has 146 total thermal storage tanks producing over 23,000 tons of cooling capacity for academic buildings. With the simple addition of more tanks to FGCU’s physical plant, it can continue running under the same operations plan that was set forth back when the university was first built.

“We’re currently going through our third expansion of the plant and preparing for future buildings that we hope to get funded in the near future,” Hehl said. “One building, in particular, is academic building nine, which is going to have a high requirement of chill water.”

“It’s sad when you walk by and see that they’re bulldozing over trees to accommodate with the expansion,” Thomas said. “but I feel that FGCU is doing their best to maintain its status as a ‘green campus.’”

When asked about dealing with potential problems such as faulty chillers or over-used storage tanks, Hehl had one word to describe his team, “aggressive.”

“My team and I are very proactive when it comes to preventative measures,” Hehl said. “With FGCU being a newer campus, it’s very easy to maintain, our guys are constantly out there oiling motors, bearings, belts and checking the filters.”

FGCU is one of only 160 campuses in 42 states that use geothermal energy to cool its classrooms.

“With the savings and the efficiency of the plant, it’s really the way to go,” Hehl said.