Dear All,
We are working on a textile manufacturing plant with a large number of washing and drying machines (using both electricity as well as natural gas). The space where the machines are installed is heated-only according to design. Since ASHRAE 90.1 requires such spaces to be modeled with cooling as well (identical to Baseline) even if no cooing exists, the heat gain from washing and drying machines is appearing as cooling loads in both the Proposed as well as Baseline cases.
Therefore, we believe that the energy performance is undeservedly penalized as the machines have very high installed electric and natural gas power and when all 100% of this cooling load needs to be mitigated by the cooling systems, a very unrealistic situation emerges where the pre-dominant energy consumption in both models becomes the cooling energy necessary for removing these cooling loads. (PS: Such energy would in reality never emerge as cooling loads as the machines have dedicated exhaust / wastewater whereby the heated air / liquid in the machines would be discarded without being in touch with the space volume).
Therefore, I have two questions:
- Is there any way that such production / manufacturing spaces that are heated only can be assigned to System #9 in the Baseline case, thereby revmoving the requirement that they should also be cooled?
- Are you aware of any study whereby the sensible heat load percentage of industrial equipment is mentioned or documented, so that we do not have to model 100% of the installed electric and natural gas power as cooling load? This would in effect point to heat loss from the body of the machines, which I believe would be the only heat that can be accounted as a cooling load in the space where the machines are located.
Thank you in advance,
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5901 thumbs up
October 30, 2023 - 4:18 pm
Sounds like a system 9 makes sense to me. Any reason why you think it would not apply?
I don't think you need to be concerned about the issue of the affect of the equipment on the cooling load. The work around for this issue (requiring a cooling system in a heated only space) before the heating only systems were available was to simply set the cooling set point so high as to make sure it never operates. You can do this because 90.1 does not regulate temperature settings. Knowing this work around it makes no sense to actually waste the modelers time to model a cooling system that will never run. All you used to have to do was point this out to the reviewer to justify not modeling a cooling system in such spaces.
Omer Moltay
Co-founderMimta EcoYapi
201 thumbs up
October 30, 2023 - 4:40 pm
Dear Marcus,
Thank you. It is my understanding that according to Appendix G G3.1.1 (e), Systems 9 and 10 are allowed for storage rooms, stairwells, vestibules, electrical / mechanical rooms and restrooms. I would think that they would not be applicable for a large space in an industrial building with various machines that are loaded / unloaded by people. However, I do believe that they should be applicable for such spaces, as such spaces would never be cooled in reality due to excessive energy costs. Therefore, I have been trying in vain to find a reference to this issue and whether there might be an exception for industrial spaces.
Regarding your recommendation, would any documented GBCI approval for this work around be available in order to take reference from?
Best,
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5901 thumbs up
October 30, 2023 - 5:47 pm
Technically 90.1 does not apply to these spaces or this equipment if you look at the scope of the standard. I have been a technical GBCI reviewer for about 20 years and our firm has reviewed somewhere around 10,000 LEED projects. Heating only systems are allowed for this type of space, they also apply for warehouses. It just makes sense to allow this type of space to use heating only systems. This "exception" cannot be found in writing anywhere in an outward facing document that I am aware of. It is unfortunate that such ruling are sometimes not all made public. If you want to double check me ask your project's LEED Coach or you can ask the LEED review team once you have begun the documentation review.
The work around I referenced may be in a LEED Interpretation but I am not certain of that. I am certain that it is embeded in the 90.1 standard itself and therefore needs no additional documented GBCI approval. We have submitted this numerous times and received approval each time. We also have reviewed it this way at least dozens of times and we do not make modelers model systems unnecessarily.