Hi all,
We have encountered a peculiar situation in our project due to a couple of factors:
- our project is a building located in a campus and receives chilled water for cooling from a District Cooling and since this is an university campus, there is no real charge being incurred from using the chilled water system;
- due to the location and type of building, the cooling energy consumption is very high compared to the other subsystems when we run our energy model
Because of these 2 factors, when breaking the percentages of energy consumption by the different subsystems, due to the weight of the cooling, all the other subsystems weigh less than 10%.
So my question is: do we have to include the chilled water from the district cooling to calculate the percentages for this credit (which would make the project require only one advanced meter)? Or should we exclude the chilled water from the calculation (which will make several of the remaining subsystems weigh more than 10%, therefore requiring more meters)?
Thank you,
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5906 thumbs up
April 13, 2023 - 6:14 pm
My first reaction as a reviewer would be that I have a hard time believing that none of the other energy end uses exceed 10%. Is this something like a data center? What is the building type and what are the loads that are driving the cooling energy use? Depending upon the answers to the previous questions the first thing I would do is question my modeling results. To answer your later questions - you must include all energy end uses and you can't exclude the chilled water.
Camilo Velez
PrincipalSimgea
21 thumbs up
April 17, 2023 - 12:36 pm
Hi Marcus,
Thank you for the answer. We are actually reviewing the model results because of this exact reason; the building is for academic/art performance, so the people and lighting loads are on the high side, but nothing like a Data Center.
What we have found in our review so far, is that although the building has a bit more of internal loads than your average office building, the reason for the cooling consumption (in terms of energy) to be around 80% of the total energy consumption, is because of it being thermal (chilled water from DES) and not electric energy, once we analyse it from the energy cost perspective (using the LEED Interpretation 100002152 for the cost of the chilled water), we get a more reasonable 50% of end use being cooling, and other end uses being over 10%. So my questions now would be:
Thank you,
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5906 thumbs up
April 17, 2023 - 1:14 pm
What is the climate zone?
Camilo Velez
PrincipalSimgea
21 thumbs up
April 17, 2023 - 2:09 pm
ASHRAE 1A - South Florida, hot and humid most of the year.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5906 thumbs up
April 18, 2023 - 5:37 pm
In your climate zone with higher than normal internal loads I could see the cooling energy being 50%. Certainly within the realm of possibilities.
Yes this credit is based on energy use not cost.
Camilo Velez
PrincipalSimgea
21 thumbs up
April 19, 2023 - 12:05 pm
Thank you Marcus for your reply and clarification.