Many students have probably heard the buzz about Deep Green’s fame as a LEED certified dormitory, but what makes it so different from any other? Aside from the aesthetics that include its architecture and woodwork that came from the college’s forest, how is it comparable to other dormitories? For that answer, one needs to pry behind hidden doors to find out.
The afternoon was unseasonably warm for November when I met up with Matthew Devensky, Berea College’s Energy Manager, or the self-proclaimed “Nuts and Bolts Guy.” His job, and passion, is maintaining the efficiency of the heating and cooling systems on the campus. Like me, he gets excited about ways to make things more efficient.
We arrived in the east parking lot and took the outside steps down to the basement where he swiped his key card to gain access. The cool darkness of the concrete made the place feel like less like the crowing jewel of Berea’s Sustainability initiatives, and more like a bunker. Devenksy inserted his keys into a large set of double doors labeled “Mechanical,” and as he pulled open the doors, the hall was flooded with the sounds of electric motors and pumps.
Mechanical rooms house the infrastructure that supplies hot and cold water, electricity and handles the heating, ventilation and air conditioning (HVAC) for the building. “Deep Green has some really new tech in it that makes use of heat transfer in new ways,” Devensky said, “I mean it’s amazing what it can do.” He leads me around the corner to see a huge white machine, rectangular in shape with pipes jutting out it on the ends. Having been used to seeing various sizes of heat exchangers and chiller units, I was amazed by the sleek compact design. This was nothing like I’d ever seen. Devensky looked at it with admiration.“This is the central unit. It takes care of all the heating and cooling for both Deep Green and Anna Smith.” He patted one of the pipes, “It’s smart, efficient, and it can take heat and put it where it needs to go with very little loss.”
Space heating and cooling is responsible for 30 to 50% of a building’s energy consumption, making it a great place to seek out the most efficiency. HVAC is all about heat transfer and sometimes it can get complicated. For instance, most people believe that air conditioners cool the air, when in fact, they are removing heat from the air and pumping it to a different place. The result is the cooler air you feel coming from the vents. In a large systems used for entire buildings, loops of hot or cold water are circulated continuously to move heat, often with machines such as chillers to remove heat to the outside, or fossil fuel boilers to add heat to the inside. Each room will have fans that blow air through coils (think car radiators) with either hot or cold water running through them for the purpose of placing heat (heating coils) or absorbing heat (cooling coils).
One of Deep Greens biggest feature is a HVAC system that can move heat where it is needed. “If some of the system is calling for cooling in some parts of the building, the heat will be removed from that area and placed into the heating systems where people are calling for heating,” Devensky explained. “If there is too much heat in the building, it will send it out to the geothermal wells beneath the parking lot where the Earth will absorb it. But that’s wasting it.”
Geothermal refers to a network of vertical wells drilled 300 feet into the earth where the temperature stays anywhere from 55° to 64° F (13° to 18°C). Loops of water pipe ran down through each well to transfer heat. Heat pumps and air conditioners which rely on electricity, and do not burn fossil fuels themselves, can remove and concentrate heat through mechanical and chemical advantages, but often rely on outside ambient air temperatures.
During the winter time, a heat pump can take what little heat is still in the air and concentrate it to pump it inside and heat a home. During the summer, it can reverse and take the heat from inside, and pump it outside. The disadvantage of using outside ambient air is that it varies greatly, so the cooler it is outside, the harder a heat pump must work to heat a home, using a lot more energy. In the summer, the outside air is warmer and it makes it harder to pump hot air into already hot air.
“But geothermal stays at a perfect temperature from which to pull heat, or dump it, and Deep Green uses nothing but heat pumps and geothermal,” Devensky said with a grin. “This makes it completely independent from our campus boiler systems that use natural gas, and massive chillers that rely on outside ambient air to dump the heat.”
If you’re interested in learning more about Deep Green and campus energy systems, contact Nick Mullins Office of Sustainability Energy and Water Conservation Coordinator by emailing firstname.lastname@example.org.