As the summer months approach, UO Facilities and Energy is looking at a way to reduce its energy consumption during peak demand.

The University of Oregon uses a chilled water system to supply cold water to the various buildings on campus. The cold water supplied goes to each building and takes heat from the room before returning to the chillers at the power station, said Paul Langley, interim co-director of utility operations at Campus Planning and Facilities Management.

The power station has five 1,500-ton chillers that supply chilled water to the various buildings on . Langley said the chillers use about one megawatt of power during the summer to cool the water for redistribution.

To save energy during the summer, Facilities and Energy will use a thermal tank, which allows the power station to distribute water from the tank during peak demand. Langley said the process would enable Facilities and Energy to discharge chilled water instead of using chillers to cool and redistribute water.

“Instead of starting a chiller, we can just discharge the water and then at night when the temperatures are cooler and we get more bang for a buck for chilling capacity, we can charge the tank back up,” Langley said.

Langley added, “We can hopefully discharge [chilled water] on heavy blow days, and if there’s a significant demand load on the power grid, we can set off our chiller plant and then discharge that tank.”

During regular operation, the power station uses five chillers to distribute the returned water across campus. The tank acts as a battery, Langley said.

Rick Tabor, interim co-director of utilities electrical at CPFM, said that a chiller is most energy efficient when performing between 30% and 60% capacity. Going over or under that range is not an optimal performance level.

If utilities and energy discharge the thermal tank, they can turn off two of the chillers and reduce the performance of the remaining three to run between 30% and 60%. They can also recharge the thermal tank at night to save energy; this is “peak energy savings mode,” Tabor said.

“By us being able to operate our chillers in the optimal performance level, it’s a major reduction,” Tabor said. “We couldn’t do this before, so that’s how we’re reducing our energy footprint.”

Underneath the campus are various pipes that distribute chilled water and steam to cool and heat campus buildings. These pipes connect the central power station and allow building staff to regulate the temperature in each building.

Water flows through underground pipes to each building and takes heat from the rooms, thus lowering the room temperature. Then, the chilled water heads back to the power plant.

Langley said that once the water arrives at the power plant, it undergoes refrigeration, removing the heat. The heat exits the building while the chilled water goes back out again. The system is a constant loop of water going to and from the power station.

Freshman student Ellison Ashley, majoring in education liked the idea of the university saving energy over the summer and said “that would be good, especially if there’s less people like living on campus during the summer to save energy.”

Sophomore marketing major Sophia Fowler agreed with Ashley, saying that it is “a good thing that [the university] is trying to save energy.”

Facilities and Energy will continue operating the many systems at the university and prepare for the summer months.