[BLDG-SIM] Baseline for Garage Ventilation using Performance Rating Method, LEED-CS 2.0
Chris Jones
cj at cr-jay.ca
Fri Apr 20 20:01:19 PDT 2007
Is there a documented why to predict the run time
hours for these type of exhaust/pressurization
systems? It seems to me they are quite intermittent with a low utilization.
At 08:02 PM 4/20/2007, gail wrote:
>The 90.1-2004 User's Manual states in Section 6.5.3,
>
>"Fans that ventilate only, such as garage
>exhaust fans or equipment room ventilation fans
>that transfer only unconditioned outdoor air, do
>not qualify as a fan system in this
>context. Fan systems must be part of a system
>with heating or cooling capability."
>
>The user's manual provides a few additional
>useful clarifications regarding what constitutes a "fan system".
>
>Garage exhaust fans, stairwell pressurization
>fans, etc. should be modeled as miscellaneous
>load, with both the CFM and BHP per CFM modeled
>identically (except the motor efficiency in the
>proposed case can be modeled as improving upon
>the requirements of Section 10.4)
>
>On 4/20/07, Scott Rushing
><<mailto:scottr at rushingco.com>scottr at rushingco.com> wrote:
>
>I've done some of the same garage exhaust fan pondering.
>
>
>
>The appendix G language is as follows:
>
>"G3.1.2.9 Supply Fan Power. System fan electrical power
>
>for supply, return, exhaust, and relief (excluding power to fanpowered
>
>VAV boxes) shall be calculated using the following
>
>formulas:
."
>
>
>
>The word "exhaust" in this section has led me to
>believe it is appropriate to use the G3.1.2.9
>formula for the baseline garage exhaust fan kw/cfm calculation.
>
>I also agree the design cfm should be the same
>in both the proposed and baseline garage exhaust system models.
>
>
>
>R. Scott Rushing, PE, LEEDAP
>
>Tel: 206.285.7106, Cell: 206.321.3300
>
>Rushing Company
>
>
>
>From:
><mailto:BLDG-SIM at gard.com>BLDG-SIM at gard.com
>[mailto: BLDG-SIM at gard.com] On Behalf Of gail
>Sent: Friday, April 20, 2007 3:05 PM
>To: <mailto:BLDG-SIM at gard.com>BLDG-SIM at gard.com
>Subject: [BLDG-SIM] Baseline for Garage
>Ventilation using Performance Rating Method, LEED-CS 2.0
>
>
>
>I would certainly like to take the Option 2
>approach mentioned for all the projects I'm
>submitting, but I'm pretty sure it's not allowed:
>
>Table <http://11.3.1.12>11.3.1.12 specifically
>lists garage ventilation fans (and exhaust fans
>also) as a "Miscellaneous load". Per the
>requirements of that section, the loads "shall
>be assumed to be identical in the proposed and budget building design"
>
>This seems to indicate that Option 1 is the only
>option that would comply with the requirements of Appendix G.
>
>Best Regards,
>Gail Stranske
>CTG Energetics, Inc.
>
>On 4/20/07, Bill Talbert
><<mailto:btalbert at aeieng.com>btalbert at aeieng.com> wrote:
>
>Neeraj,
>
>I would agree that your interpretation and your
>proposed 'option 2' appear to be meeting the
>requirements of App G. The LEED NC V2.2
>Reference Guide (refer to EA Credit 1
>Calculations for 'Other Systems,' page 182)
>indicates that where specific energy efficiency
>requirements exist in A90.1, the lowest
>allowable efficiency shall be used for the
>Baseline. Garage ventilation is included in the
>sample listing of 'other' systems and the fan
>power allowance should apply to that system. Not
>sure whether LEED CS V2.0 has something equivalent.
>
>
>
>That said, I am not a LEED reviewer. It would be
>interesting to hear what others think on this as
>the fan power allowance is likely easy to beat
>for a ventilation only system where system
>pressure drop is minimal. I would expect that
>the intent of App G may not be to 'credit' these types of systems.
>
>Bill Talbert, AEI
>
> >>> neeraj
> <<mailto:near_ej at yahoo.com>near_ej at yahoo.com> 4/20/2007 1:14 PM >>>
>
>Hi all,
>LEED, Core and Shell V2.0
>A 300,000 sqft building, 12 stories above ground
>located in Washington DC. The baseline building
>is System # 8, i.e. VAV fan controlled, PIU, all electric heating and cooling.
>Problem Area -- To determine a correct Baseline:
>In the proposed design, 3 levels of underground
>parking garage are merely ventilated with
>constant volume fans and they are not equipped
>with CO/NOx sensors , i.e. they are merely constant volume, SA and EA fans.
>We know that garage ventilation is not process
>energy, so it must be regulated somehow, right?!
>Plus, we cannot take credit for energy savings
>from OA ventilation air (according to Appendix
>G). Now, since this is a 'fans only' situation
>in both the models (no cooling or heating) I
>have assumed the CFM of OA ventilation air must
>be the same in both cases. Am I correct, so far?
>Using this as a premise, the following two
>contradicting scenarios for an appropriate
>baseline model can reasonably be thought of:
> * Model similar SA and EA CFM as in the
> "Proposed Building Model" with similar fan power kW/CFM, OR
> * Model similar SA and EA CFM as in the
> "Proposed Building Model" but calculating the
> fan power for the OA flow using Section
> G3.1.2.9 of the Informative Appendix G of ASHRAE 90.1-2004.
>
>THE BIG QUESTION(s): Is the second option a
>valid approach for determining fan power (kW/CFM) for the baseline?
>
>OR
>
>Is the method only meant for determining (and
>thus crediting/penalising) system supply air fans and not parking garage fans?
>
>Thanks,
>Neeraj
>
>
>
>Ahhh...imagining that irresistible "new car" smell?
>Check out
><http://us.rd.yahoo.com/evt=48245/*http:/autos.yahoo.com/new_cars.html;_ylc=X3oDMTE1YW1jcXJ2BF9TAzk3MTA3MDc2BHNlYwNtYWlsdGFncwRzbGsDbmV3LWNhcnM->new
>cars at Yahoo! Autos.
>
>======================================================
>
>
>You received this e-mail because you are subscribed
><mailto:BLDG-SIM at GARD.COM>
>
>to the
>
>
><mailto:BLDG-SIM at GARD.COM>BLDG-SIM at GARD.COM mailing list. To unsubscribe
>
>
>from this mailing list send a blank message to
><mailto:BLDG-SIM-UNSUBSCRIBE at GARD.COM>
>
>
>
><mailto:BLDG-SIM-UNSUBSCRIBE at GARD.COM>BLDG-SIM-UNSUBSCRIBE at GARD.COM
>
>
>You received this e-mail because you are subscribed
>
>
>to the
><mailto:BLDG-SIM at GARD.COM>BLDG-SIM at GARD.COM mailing list. To unsubscribe
>
>
>
>
>from this mailing list send a blank message to
>
>
><mailto:BLDG-SIM-UNSUBSCRIBE at GARD.COM>BLDG-SIM-UNSUBSCRIBE at GARD.COM
>
>
>You received this e-mail because you are subscribed
>
>to the
><mailto:BLDG-SIM at GARD.COM>BLDG-SIM at GARD.COM mailing list. To unsubscribe
>
>
>from this mailing list send a blank message to
>
><mailto:BLDG-SIM-UNSUBSCRIBE at GARD.COM>BLDG-SIM-UNSUBSCRIBE at GARD.COM
Chris Jones
14 Oneida Avenue
Toronto, ON M5J 2E3.
Tel. 416-203-7465
Fax. 416-946-1005
===========================
You received this e-mail because you are subscribed
to the BLDG-SIM at GARD.COM mailing list. To unsubscribe
from this mailing list send a blank message to
BLDG-SIM-UNSUBSCRIBE at GARD.COM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20070420/ef2e326d/attachment-0002.htm>
More information about the Bldg-sim
mailing list