‘Occupancy Sensor’ Furthers Sustainabilty Initiative
Published: Thursday, September 13, 2012
Updated: Thursday, November 15, 2012 01:11
As part of a sustainability and energy efficiency initiative, the College has installed monitoring devices in student residences that will adjust the room temperature based on whether students are in the room. These “occupancy sensors,” as Sustainability Director Ed Neal described them, are connected to thermostats installed in the residence halls. Neal expects these sensors, combined with a host of other campus renovations, to produce up to a 30 percent reduction in the amount of energy the College uses.
The thermostats and occupancy sensors give students control they didn’t have before, Neal said. In the past, students reported bad experiences with preexisitng units. Neal cited tales of students who would return from breaks to find “their goldfish [were] dead” because the room had gotten too hot. Additionally, some room windows were often left open over the summer with the air conditioning still active, wasting energy.
When a student sets his or her preferred temperature on the new thermostat, the unit stores that preference alongside a preprogrammed minimum temperature. If the occupancy sensor determines no one is in the room, it sends a message to the thermostat to revert to the minimum temperature, preventing energy wastage.
When a student returns to the room and the sensor detects him or her, the thermostat automatically readjusts to the student’s preferred temperature.
“I wanted the project to be something where we can actually save energy but nobody’s paying a big sacrifice to make that happen,” Neal said.
The occupancy sensor, fixed on the ceiling, resembles a smoke detector with two solar panels and can detect both heat and motion. “If you fall asleep, you’re not going to wake up freezing,” Neal said. “It will know that you’re in the space.”
Maintenance workers began installing the sensors and thermostats over the summer and have continued working on the project into the school year, according to Neal. The thermostats and sensors are present in Mather, McBride and Caples Residence Halls on North Campus and Hanna, Leonard and Old Kenyon Residence Halls –– which have heat but no air conditioning –– on South Campus.
Mather, McBride and Caples Residence Halls use blowers with three basic settings (low, medium and high) to regulate temperature. Using the new thermostats, students get to pick a specific temperature and the College can reduce its energy expenditure. “We think this is going to be better for students and for our energy conservation measures,” Neal said. (In those dorms that have blowers, students can still switch them off, but when they are left on, the thermostat controls them more efficiently.)
Other dorms, Neal said, either do not have blower units in the rooms or, in the case of more modern buildings, already have smarter “building automation” equipment. In those newer residences, “this also allows the facility guys in maintenance to remotely see the temperature. So if there’s a room that’s in trouble, they’ll get an alarm telling them it’s cold or it’s hot and they may be able to fix it before you even know you have a problem,” he said.
The occupancy sensors are a part of the College’s new sustainability initiative, which Neal said would reduce energy usage from electricity, water and natural gas between 28 and 30 percent. The overall program also includes new lighting fixtures, adjusted showers and toilets and mechanical upgrades to steam units and basement air handlers. “When the project is complete,” said Chief Business Officer Mark Kohlman, “the College expects to save $600,000 annually from reductions in energy and water usage.”
The maintenance department installed new lighting fixtures in numerous buildings that conserve energy and improve the environment. The fixtures also provide better light in dorm rooms. Last year, they also replaced dorm showerheads and toilets, which now use a “low-flow” water system.
Maintenance workers are also upgrading the air handlers in various buildings to use systems called variable-frequency drives. These modifications will allow for smarter management of the airflow inside upgraded buildings. “The old control systems that they had basically, when nobody in the building needed anything, it would take that heat or [cold air] and throw it outside because energy was cheap at one time,” Neal said. “Now, we’re actually going to be able to use only what we need to use.”
More programs that promote energy sustainability are under way. “You’re going to see a lot of things that we’re doing to try to be more frugal and manage our energy to the best that we possibly can and reduce our carbon footprint to do our part to protect the environment,” said Neal.
Other projects include upgrades, such as shutting down Kenyon’s central steam plant next summer and replacing it with satellite boilers.
Smarter energy monitoring equipment is also in the works for the whole campus. “We are installing, in the mechanical spaces, water meters, electricity meters [and] steam meters so that we know what individual buildings are doing,” Neal said. Once this process is complete, students will be able to modify their electricity consumption habits accordingly.
These sustainability efforts, according to Neal, serve to increase energy usage awareness. “This project does have a behavioral modification program, which is an educational thing,” he said. “It’ll tell us all about all the initiatives that we’ve done. On our campus, we don’t have to convince you to do better. If you know what better is, you’ll do it. [With] the behavioral modification portion ... we’ll bring out all these initiatives and say, ‘This is what we did, this is why we did it and this is how it works.’”
“We think this is going to be better for students and for our energy conservation measures,” Neal said. “It’s going to save energy for us, reduce our carbon footprint and provide the students with a level of comfort they don’t have right now.”