Modelica-based modeling and simulation of district cooling systems: A case study

While equation-based object-oriented modeling language Modelica can evaluate practical energy improvements for district cooling systems, few have adopted this type of large-scale thermo-fluid system. Further, to our best knowledge, studies yet include hydraulics in piping networks alongside plant models featuring realistic mechanical systems and controls. These are critical details when looking make control many physical system installations. To fill these gaps, study released new open-source at the Buildings Library leveraged a real-world case University Colorado Boulder. The site includes six buildings connected central chiller waterside economizer. Several saving strategies pursued based on validated model, including setpoint optimization, equipment modification, pump adjustments. Results indicate that combination studied measures save campus annually 84.6 MWh energy, 8.9% electricity costs, 58.0 metric tons carbon dioxide emissions, while economizer cuts down chillers’ run times by 201 days/year, reducing maintenance costs extending life.