North Carolina State University’s (NCSU) Centennial Campus is growing with new buildings such as Plant Sciences and EB Oval and with loop additions including the College of Textiles and Monteith Research Center. This project design expanded central chilled water plant capacity with the addition of a stratified chilled water thermal energy storage tank (TES).
During advanced planning stages, options and comparative analysis were developed for each element of the design. The tank was sited to minimize grading and structural retaining walls while remaining accessible and relatively obscure from primary campus views. A deep foundation system consisting of H-piles to bedrock was selected to minimize settlement. Tank aspect ratio was selected to ensure that top of water elevation was at the tallest point on campus yet align well with the top elevation of the adjacent chiller plant. During this stage of design, RMF provided a detailed comparison of steel vs concrete tank construction with consideration for cost, construction, operations, and maintenance.
An energy model was developed to optimize TES charge and discharge cycles for standard large general service and large general service time-of-use rate structures. Graphical dashboards, key performance indicators and automatic controls sequencing was then developed based on the energy model output. In addition, RMF also provided sequencing and integration of a nearby steam turbine generator (STG).
