Dear Sirs,

I am modeling a school building for LEED which has a Campus Energy System (water cooled chiller and diesel boiler). The DES was installed almost 8 months ago for the first phase of the project.

Now, I am modeling for the project's second phase, and additional chillers / boilers will be added to the DES in order to be able to serve both phases in addition to any potential building on campus in the future.

1) Looking at the USGBC's guidance for DES (Appendix C): in order to determine the proposed building heating / cooling efficiency, I guess I have to go with the "Modeling" option because the DES will be expanded as part of my project (so it's not existing).

For this option, do I have to create a separate model of the district plant, or shall I add this district plant to my project's model? Appendix C says "Apply measured or estimated load profiles as "process loads" to reflect the estimated total loads on the plant". If this is the case, then if I add the process loads in addition to my project's loads, I will be double counting the loads, right?

Does this mean I have to create a dummy project building (with no loads) with the proposed district plant to determine the efficiencies?

2) Does anyone have additional guidance for modeling district energy systems, other than the one of the USGBC? Something with more examples or maybe a case study with actual numbers?

Best regards,
Omar
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Omar Katanani