SAN FRANCISCO — A chilled-water system at the University of California, San Francisco (UCSF) recently earned a $757,000 energy efficiency award from PG&E. Designed by San Francisco-based Arup, the system also received the 2013 Higher Education Energy Efficiency and Sustainability Best Practice Award in the HVAC Retrofit category. Constructed between August 2011 and December 2012, the $7.7 million project helped UCSF upgrade its water chilling system to a highly efficient system from its former inefficient absorption chillers. The new chillers will distribute water to both hospitals on UCSF’s campus.
There were three main goals for the project, according to Sukhjeet Sandhu, facilities director at the UCSF Medical Center. “There was a revitalization goal to renew [UCSF’s] cooling system infrastructure and add capacity; there was a goal to reduce operational costs by over $1 million per year; and there was a goal not to let the system go down during the construction,” Sandhu said.
The result of the project was a significant increase in energy efficiency and decrease in energy costs. The new chillers will save the school $1.3 million in utility costs and over $100,000 in maintenance costs annually, according to PG&E. The chillers are expected to pay for themselves in as few as six years.
Several major design elements characterized the project. The project team had to reinvent the central chiller plant in order to serve both hospitals instead of just one, which maximized the project’s value, according to Sandhu. This consisted of converting the multiple dysfunctional primary-only pumping systems to a modernized variable-speed primary and secondary pumping system, planning a detailed infection control system in order to replace the three-way chiller valves with two-way ones near patient care areas, connecting the university’s Long Hospital’s chiller system to Moffitt Hospital’s new chiller system, and implementing a new control system that automates the chiller’s operation and helps calculate the university’s energy savings.
The project team managed to perform the major overhaul of the university’s chilled water system while also keeping the hospitals operational during construction. “To ensure that the medical center remained operational during these extensive renovations,” Sandhu said, “Arup devised a step-by-step logistical approach using stents, similar to the concept of heart surgery, that allowed specialty contractors and pipe fitters to work on parts of the chilled water lines while water flowed through the bypass lines.”
Arup completed the renovations smoothly, without disturbing the operation of either hospital. “The patients and staff never even knew we were doing this work, so we more than accomplished the goal for non-interruption,” Sandhu said.
When asked to comment on the PG&E award the school received, Sandhu said that it “represents the largest energy efficiency rebate for a single project at UCSF and was the first large-scale energy improvement initiative completed at the medical center. Within an operating hospital under California’s stringent OSHPD jurisdiction, Arup helped UCSF to reduce operations and maintenance costs, utility costs, and greenhouse gas emissions while greatly improving service reliability, system performance and cooling capacity for future growth.”