Hi all,
I've been reading some of the previous comments about the humidity controls (both humidification and dehumidification). Am I correct to assume:
a) Humidification must be modeled identically (same setpoint) in both models and its energy consumption is "process energy"; If so, it is likely that the energy consumption of the Baseline would be different than of the Proposed design: in this case I may manually post-process the Baseline's humidification energy consumption to match the Proposed so that "Process Energy" is equal in both builings.
b) Dehumidification shall be modeled identically (same setpoint and supply air temperature for RH control) in both models, but I'll consider it "Regulated Load" since the load comes all out from the same chiller;
Also I have a doubt regarding the "unmet load hours" (as there are limits in temperature - 300 ULH) for the RH control: is there any mandatory provision that requires the Baseline and the Proposed to have the same number of hours that meet the design RH? Or is it just sufficient to model identical setpoints / controls ?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 thumbs up
November 1, 2017 - 9:30 am
a. The energy use will likely be different and that is OK. No need to make the energy use identical.
b. The dehumidification set point is the same but not necessarily the same supply air temperature in both models.
It is sufficient to model the same set points/controls.
Luis Andrade
3 thumbs up
November 6, 2017 - 11:19 am
Thank you Marcus!
I forgot to ask you: should I consider dehumidification as process or as regulated load?
Thank you in advance!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 thumbs up
November 6, 2017 - 11:51 am
Dehumidification for people related space conditioning purposes is a regulated load.
Luis Andrade
3 thumbs up
November 6, 2017 - 12:16 pm
Thank you Marcus!
I'm sorry to be pushing this question but I'm still having doubts.
These controls exists in occupied (exhibition rooms) and unoccupied spaces (warehouses).
It is our understanding that RH controls are intended for art work preservation. How should I consider them in:
1) Exhibition rooms?
2) Warehouses?
Thank you in advance!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 thumbs up
November 6, 2017 - 12:37 pm
The more specific you can make your questions the easier they are to answer. When you ask general questions you get general answers.
In both space types the dehumidification settings are likely to be similar to what you would have to condition the space for people so I don't see a difference there. Many museums and places that exhibit and store art adhere to a 70/50 temperature/humidity setting year round (although this is often not necessary). For dehumidification this is pretty close to what you might have for people occupancy anyway. If the RH dehumidification setting in either space is significantly lower than what one would expect for space conditioning for people then it may be partially process but it becomes potentially difficult to separate what is process from what is not. It sounds like both space types are fully conditioned so the issue of regular occupancy does not matter. We already established that humidification is a process load.