Dear All,

 
According to the section “Further Explanation” of the LEED Web guide, projects that are served by district energy systems (DES) and follow Option 1 (Whole Building Simulation) Path 1 (ASHRAE 90.1-10 Appendix G ) may demonstrate compliance with EA Prerequisite Minimum Energy Performance and EA Credit Optimize Energy Performance by modeling the proposed case with a virtual DES-equivalent plant. When information regarding existing DES efficiency is not available, default values may be assumed, namely:

  1. DES heating plant: 70% (higher heating value, HHV) for the total boiler plant average efficiency
  2. DES cooling plant: coefficient of performance (COP) of 4.4 for the total cooling plant average efficiency (including cooling towers and primary pumps)
    • Thermal distribution losses including minor leaks or condensate losses:
    • Chilled water district cooling, 5%
    • Hot water district heating, 10%
    • Closed-loop steam systems, 15%
    • Open-loop steam systems, 25%

Do you validate our interpretation?

Thanks in advance,