We are working on a Manufacturing Project in Vietnam with very high non-regulated loads (around 75% of the total energy consumption). It is designed without air conditioning, mechanical ventilation will provide adequate thermal comfort at a level acceptable in the tropics. I have a question related to the same project and credit but regarding the validity of this LEED Interpretation for LEED v4. I still would like to know if anyone has experience or insight on the following question in case we need to pursue this path.
For this project, the Energy Modeling for EAc2 will require us to simulate cooling that is not part of the design to achieve the right indoor temperature and humidity as required by ASHRAE 90.1. As the volume of the spaces is large, a lot of equipment and an envelope designed to be light and open up for natural ventilation, the extra cooling load becomes particularly large (approximately 20GWh/year), about 200% more than the total actual expected consumption (approximately 10GWh/year).
My question is, is there a case for us to use the actual naturally ventilated consumption simulation result for EAc5, considering that EAc2 consumption will give a result 3 times higher than what we actually expect? Has anybody faced this issue before?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5906 thumbs up
May 29, 2018 - 10:51 am
Regarding that particular interpretation I would send an inquiry to GBCI to see if it applies to v4 projects.
Regarding your operative assumption that cooling must be modeled, there is a way around this requirement. 90.1 does not require any particular temperature or humidity level. The only requirement is that the temperature setting must be identical in both models. So projects that are forced to model systems that do not exist will often just set the temperatures so that the system never comes on. You could do that but knowing this is an option most reviewers will not require you to model the systems if you tell them that it is a waste of your time because you will just set the temperatures so that the system will not operate. Knowing this work around will allow you not have to do the busy work of modeling a system that will have no affect on the energy use. Doing this would eliminate your question about using different values for EAc5.
Tim Middleton
Technical ManagerVILANDCO
3 thumbs up
June 5, 2018 - 3:06 am
Thanks for this insight Marcus. We will give your suggestion a try because it makes a lot more sense.