Sustainability: Interconnected Chiller Plant

A primary project identified from the Sustainable Energy Master Plan was the interconnection of chiller plants on the “superblock” of the Medical Center. What this meant was to install piping to connect chilled water piping in buildings and chiller plants across the Black Building, P&S Building and Hammer Building.

While this sounds like a simple plan, to run piping, in actuality, it was quite an engineering feet. Over 400 feet of 16 inch diameter chilled water supply and return piping was run between our Black chiller Plant and the basement of the P&S building to connect the systems.

Interconnecting the plants means that instead of using three different chiller plants to run three different buildings, we are now able to utilize one chiller, most days, to operate the three buildings. On severely hot days, however, or if there is an issue with the primary chiller plant, we also have the option of running additional plants. Not only does this provide additional redundancy in case of an emergency, it also helps to reduce the overall chilled water utility consumption across the campus, in other words, improving our efficiency and reducing our carbon footprint. The installation of this piping also included an additional controls upgrade of the chiller plant, which allows the system to perform a checks and balances on its operation and ensure optimal operating condition.

While we finalize the controls portion of this project to conclude optimization in time for this next summer season, we also look forward to additional improvements on the plant that will continue to reduce consumption. These additional improvements include a pumping optimization plan that will allow the pumps that distribute the chilled water for air conditioning to ramp up and down according to demand, as well as an optimized dispatch schedule for when it is most cost-effective and efficient to run each chiller plant, as well as each individual chiller. Both of these additional optimizations will not only assist in improving efficiencies, but will also help with the life and performance of the chillers themselves as they continue to age.

Please direct questions and/or comments to cumc-energy@columbia.edu.