At the Energy Conservation Office, we are always looking for opportunities to improve energy efficiency and campus comfort. One way we can accomplish both goals is by incorporating ceiling fans in large classrooms. The most ideal ceiling fans for this project are high volume, low-speed (HVLS) fans that can circulate a high volume of air throughout a large space efficiently, which can reduce the need for heating and cooling. Comfort can also be improved by HVLS fans because classrooms can maintain a more consistent temperature without disrupting comfort.
Giedt Hall Room 1001 was chosen as our pilot classroom to install two fans selected from a company called Big Ass Fans ©, which are guaranteed to operate silently. We installed the fans during the summer of 2017. Over the six months, we tested experimental conditions during the Fall and Winter Quarters to evaluate comfort improvement and energy savings.
- Baseline Period: fan off and no changes to existing classroom temperature setpoints (Summer 2017)
- Experiment 1: run the fan at a single default speed, and adjust the classroom temperature setpoints to a more energy efficient setting (Fall 2018)
- Experiment 2: fan controlled through TherMOOstat votes, and adjust the classroom temperature setpoints to a more energy efficient setting (Winter 2018)
In order to ensure the fans are serving the people in the room efficiently, we connected TherMOOstat feedback to the fan's operation to allow students and faculty to participate in their own thermal comfort. Their participation can provide quick adjustment to their comfort and provide trend data for future settings.
Providing control of the fans to students and faculty helps us understand how people actually feel in their space and their comfort needs; however, we wanted to take a step further to make sure the fans are working at the top, optimal level. We added code to the fans to turn on or off based on expected occupancy in the room and set a default speed where we receive no votes. Outside air temperature is also taken into account so when you first enter the classroom, the fans will operate at the optimal speed.