In celebration of Earth Day, Central New Yorkers will have the chance on Saturday to visit more than 20 sites across Onondaga County to see how they’re using renewable energy. We chose three of them and are starting with with a geothermal system underneath the pike block in downtown Syracuse.
President of IPD engineering Sam Cosamano walked through a series of doors to the mechanical room in the basement of the Witherell building.
“The high pitch whining that you’re hearing here, these are pumps running at variable speed to keep up with the needs of the building.”
The pump underneath the sidewalk on Salina Street extracts brine from an aquifer 50 to 60 feet below the basement floor. The brine then runs through filters, followed by a titanium plate heat exchanger, before being reintroduced to the aquifer under Clinton Street. Cosamano said this open loop system cost only 10 to 15 percent more than a conventional heating and cooling system, but saves much more on energy.
“We believe that it’s costing us about half of the operational cost of a conventional system. So we are not using gas fired boilers to heat in the winter, and we’re not running a cooling tower and using a lot of make-up water in the summertime.”
Cosamano says even the pumps themselves are designed to be energy efficient, something relatively new to geothermal systems.
“We put a variable speed drive on the pump in the ground, so we’re not always pulling the same amount of brine out of the ground. We’re looking at how much energy the building needs to consume, and we’re only driving the pump as hard as we need to. So, some days we may be only pulling a little brine out of the ground, and other days we may be pulling a lot of brine out of the ground. That helps us conserve energy, too.”
But Cosamano says there were some early complications with the now-three year-old system.
“In our first year, the heat exchanger started to clog up on us. We investigated and there was iron based bacteria that we were getting out of the ground. So, we did a little bit of chemical engineering. As it turns out, by injecting just a little bit of hydrogen peroxide into the extraction well, we’re able to keep that under control.”
And, he says, it’s worked well since. But convincing customers to go geothermal for new construction or system overhauls isn’t always easy. Cost is one factor, especially if it’s a closed loop system. Then, the open loop system like the one downtown has inherent risks.
"With conventional systems, you kind of know what you’re getting. When you’re drilling into the ground, you don’t really know what you’re going to get. So, if you have a critical building, and you want to make sure the system is going to work, some customers shy away from systems like this.”
He says the risk is paying off for the pike block. The system heats and cools about 30,000 square feet of ground floor commercial space.
Tours are available Saturday from 11 a.m. to 3 p.m. More information on the self-guided tour of renewable energy systems at 21 locations is at ccawarenessaction.wordpress.com