P2S was contracted to perform an MBCx commissioning on the central plant at Cal Poly in Pomona, California. MBCx, monitoring-based commissioning, takes a fresh look at central plant operations, evaluates what is operating well, what needs to be improved and what should be done in the future. The work is limited to controls and operational changes. Capital improvement is not included.
The primary challenges included performing commissioning work on a continuously operating central plant while identifying any and all the savings and operational opportunities. It also gave an opportunity to gain a better understanding of the plant’s controls and chiller operation.
Commissioning revealed that while the TES system charges its pumps operate. This feeds the chiller supply header from two ends. and causes a mismatch in chiller loading when the temperature from the TES tank is different then the temperature from the return of the campus loop. The chiller system was then configured for just primary pump operation and the TES pumps were permanently turned off. This improved efficiency and reduced chiller wear and tear. A capital improvement recommendation designed to improve efficiency: install a 600-ton VFD chiller that will operate when the TES tank is charging. This would also help extend the TES tank during hot weeks in the summer months by operating 24 hours a day.
Prior to commissioning the annual electrical energy consumption of the chiller plant baseline was 5,777,600 kWh.
The post electrical energy consumption of the chiller plant after MBCx was 5,177,500 kWh. The projected electrical energy consumption of the chiller plant after the 600-Ton VFD chiller, and new control system installation is 3,998,300 kWh.
A total electrical energy savings of 600,100 kWh was achieved with the MBCx project.