Hi. We are applying for LEED certification for a building housing a Central Utility Plant (CUP) which supplies district energy to a hospital campus. I'm using Trane TRACE to model the CUP building for EAc1 credit (Option 2). LEED has developed a related document -- "Treatment of District or Campus Thermal Energy in LEED V2 and LEED 2009" -- but I have found it fairly unclear on how the plant should be modeled.

Following ASHRAE 90.1 Appendix G standards for the baseline model results in a small plant that only meets the cooling and heating loads of the CUP building itself. Our proposed model, by comparison, includes a massive plant that significantly exceeds the CUP building's HVAC loads. This plant, obviously, meets such a small load with less efficiency.

My question is this: If the building seeking LEED certification houses only a District Energy System, how should the plant and loads be modeled? Should the baseline and proposed models include the hospital campus loads? Should the baseline model be sized to meet the campus loads?

Thanks in advance for your assistance.