We're working on a 35,000 SF lab building on a campus district cooling loop. The baseline system type is #5, so there's no chilled water in the baseline. The project overcoming the process heat from the lab equipment using the district loop's chilled water (similar to using a separate process chiller).
The question is: Will LEED accept a model that uses System Type #5's airside equipment to cool the process load in the baseline, and then uses the district chilled water to cool the process load in the proposed?
Fundamentally, choosing to cool the process load with chilled water is an energy efficiency measure that should get credit for the energy savings. However, with our default typically being to make process loads equal between the baseline and proposed, there's been some conversation around if we need to model a chiller in both the baseline and the proposed for this case. Does anyone have experience with this situation and can offer feedback?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5928 thumbs up
March 28, 2025 - 10:41 am
Since this is for a process load the models should be identical. If you wish to claim savings then you would need to perform an exceptional calculation and justify the use of an air cooled system in the baseline as standard practice.