Hi all,

My project has a central plant supplying chilled water to each building, as district cooling. The central plant consists of cooling towers, chillers and ice storage. The produced chilled water is distributed and pumped to plant rooms in each building.  

As our project has an on-site plant, we would like to use Option 1 Whole building energy simulation: Path 2 Full DES performance accounting. If we use engineering analysis, total energy saving is calculated by combining each building’s ones, which needs to input an average efficiency and lose of the central plant.

  1. Can I get some advice on a method to estimate an average efficiency of a proposed case model (This model only contains upstream equipment – cooling towers, chillers and ice storage, right?)? Is it correct to follow this reference, “Treatment of District or Campus Thermal Energy in LEED V2 and LEED 2009 – Appendix C”2?
  2. Once I have an estimated average efficiency, do I input the efficiency for a separated energy model of each building to claim energy saving?