WUSM Central Chilled Water Loop System – Upgrade and Optimization

This month, WUSM completed a project to further optimize the flow of chilled water to several buildings, resulting in lower usage of electricity from the chilled water system that provides space conditioning to many of the buildings. These buildings are cooled year-round via a distributed system of chiller plants interconnected by supply and return piping. Chilled water is circulated to the buildings by pumps that are equipped with variable speed drives so that the pumps can be slowed down via automated controls, thereby moving less water and using less electrical energy during times when the building cooling loads are reduced.

The project largely involved building automation programming changes that fine-tune the control of each building’s bypass valve in order to reduce chilled water loop flow. Additional energy savings benefits are expected, such as improving chiller plant loading for higher efficiency operation and, at times, reducing the number of chillers operating to meet cooling loads.

Buildings involved in the project include: East, West, North, and South Buildings, as well as McMillan, Maternity, Cancer Research, Biotech, CSRB, and FLTC. The project is expected to have a simple payback of less than two years.