[Equest-users] Demand Controlled Ventilation and EA Credit 1

[Carol Gardner]

I'm sorry for not being clear, but I've had little sleep in the last few
days cause of a darn project. I don't really change the occupancy schedule,
rather I create a DCV schedule which is sort of based on the occupancy
schedule but w/ hrs reduced to reflect them coming and going from meetings
or whatever the space is used for. It's probably what the new DCV commands
do in eQUEST, I just haven't had the time or opportunity to use them yet.

Carol

On Tue, Jul 27, 2010 at 11:51 AM, Paul Riemer <Paul.Riemer at dunhameng.com>wrote:

>  Ron and Carol,
>
> Would you please clarify by referencing EQUEST/DOE-2.2 commands? Are you
> modeling DCV by changing the space occupancy schedule (SPACE:
> PEOPLE-SCHEDULE)?  What are your outside air inputs?  Is this the dummy
> space in a  DOAS system? Are you making other creative changes like putting
> all of your occupant heat gain in as a process load?  I am gasping to
> understand the validity of changing the people schedule.
>
>
>
> I have always valid DCV modeling is best done in eQUEST/DOE-2.2 by changing
> the system minimum outside air schedule (SYSTEM: MIN-AIR-SCH).   Even just
> changing the system minimum outside air control method (SYSTEM:
> MIN-OA-METHOD) seems iffy because I think the approach that ignores the
> floor area component of Std 62.1.
>
>
>
> Thanks,
>
> Paul Riemer
>
> Dunham
>
>
>
>
>
> *From:* equest-users-bounces at lists.onebuilding.org [mailto:
> equest-users-bounces at lists.onebuilding.org] *On Behalf Of *Bishop, Bill
> *Sent:* Tuesday, July 27, 2010 1:32 PM
> *To:* James Hansen; ron lamarre; equest-users
>
> *Subject:* Re: [Equest-users] Demand Controlled Ventilation and EA Credit
> 1
>
>
>
> Ron,
>
> I’m with James on this one. I can see changing lighting or equipment
> schedules to capture ECMs but changing occupancy schedules makes no sense
> unless you’re modeling telecommuting or 4-day work week. You can capture DCV
> savings in eQUEST by selecting DCV as the Minimum OA Control Method for the
> system and having an occupancy schedule with a varying percentage (not 100%)
> during occupied hours. Using the same occupancy schedule, the model with DCV
> will heat/cool less OA air and show savings.
>
> Regards,
>
> Bill
>
>
>
> *William Bishop, PE, BEMP, LEED® AP **|** Pathfinder Engineers &
> Architects LLP*
>
> Mechanical Engineer
>
>
>
> 134 South Fitzhugh Street
> Rochester, NY 14608
> T: (585) 325-6004 Ext. 114
> F: (585) 325-6005
>
> wbishop at pathfinder-ea.com
>
> www.pathfinder-ea.com
>
> P Sustainability – less is more.
>   ------------------------------
>
> *From:* equest-users-bounces at lists.onebuilding.org [mailto:
> equest-users-bounces at lists.onebuilding.org] *On Behalf Of *James Hansen
> *Sent:* Tuesday, July 27, 2010 2:23 PM
> *To:* ron lamarre; equest-users
> *Subject:* Re: [Equest-users] Demand Controlled Ventilation and EA Credit
> 1
>
>
>
> “For the record, the occupancy schedule refers to the people present
> within the space.  For instance, a space within the baseline (not required
> by ASHRAE to have DCV) would have the max number of occupants for the entire
> occupied-mode schedule; however, the proposed would have the max number of
> people for only as many hours as submitted in the project narrative for FTE
> usage of the space, and a minimum number of people (or no one) for the
> remaining occupied-mode time.  Thus we create an occupancy (people) schedule
> for the space.  During the unoccupied mode the fans would cycle as
> required with no people, no lighting (automatic shut off), acting on the
> heating & cooling loads.  We would not install DCV if the occupant loads
> didn't change during the occupied mode.”
>
>
>
> Ron, please educate me if I’m reading your email wrong, but are you saying
> that your occupancy schedule in the proposed design does not match the
> baseline design? This is strictly prohibited in App G I thought… You can
> change schedules to take advantage of non-standard ECMs like DCV, and
> automatic lighting reductions for the use of occupancy sensors (in rooms NOT
> already required to have them by code). But having a conference room 100%
> occupied from 7am-6pm in the baseline model and only 100% occupied from
> 9am-noon in the proposed model is not a valid way to demonstrate savings
> from DCV, since there will be energy savings related to the people
> latent/sensible production that has nothing to do with DCV. Don’t you have
> to create a minimum outside air schedule to demonstrate DCV savings? If you
> have received credit for simply reducing the Occupancy Schedule in the
> proposed model, that is very interesting…
>
>
>
> Thanks!
>
>
>
> *GHT Limited
> **James Hansen**, PE, LEED AP*
>
> *Senior Associate***
>
> 1010 N. Glebe Rd, Suite 200
>
> Arlington, VA  22201-4749
>
> 703-338-5754 (Cell)
>
> 703-243-1200 (Office)
>
> 703-276-1376 (Fax)
>
> www.ghtltd.com
>
> * *
>
>
>
> *From:* ron lamarre [mailto:lamarre_arch at yahoo.com]
> *Sent:* Tuesday, July 27, 2010 2:08 PM
> *To:* James Hansen; equest-users
> *Subject:* Re: [Equest-users] Demand Controlled Ventilation and EA Credit
> 1
>
>
>
> Hi James:
>
>
>
> For the record, the occupancy schedule refers to the people present within
> the space.  For instance, a space within the baseline (not required by
> ASHRAE to have DCV) would have the max number of occupants for the entire
> occupied-mode schedule; however, the proposed would have the max number of
> people for only as many hours as submitted in the project narrative for FTE
> usage of the space, and a minimum number of people (or no one) for the
> remaining occupied-mode time.  Thus we create an occupancy (people) schedule
> for the space.  During the unoccupied mode the fans would cycle as
> required with no people, no lighting (automatic shut off), acting on the
> heating & cooling loads.  We would not install DCV if the occupant loads
> didn't change during the occupied mode.
>
>
>
> We also use general lighting schedules that take advantage of installed
> occupancy sensors, and process load schedules that take advantage of Energy
> Star computers and monitiors.
>
>
>
> The HVAC engineer decides the minimum design rate for each space to work
> (heating & cooling) if fully occupied with all the lights, process loads,
> and people during the occupied mode.  This is normally at or above the 62.1
> and/or other code-required minimums (never below due to the LEED
> pre-requisite).  Sharing the reduction schedules placed into eQuest with a
> template-narrative to support the reductions (based on ASHRAE 90.1, Energy
> Star, etc... %-reductions) has been accepted by LEED.
>
>
>
> We utilize an integrated design team method, where the engineers and
> I review the models that I construct.  We also get peer reviews when we
> think it's necessary and/or when LEED throws us a curve.  We pay for our
> peer reviews.  I'm confident that anything we've submitted does not prove
> inconsistency within the review of EAc1.
>
>
> *Ron Lamarre, AIA, NCARB*
>
> Architect - *LEED AP BD+C*
>
>
>
> *Design  +  Energy Modeling + LEED Administration*
>
>
>
>
>  ------------------------------
>
> *From:* James Hansen <JHANSEN at ghtltd.com>
> *To:* ron lamarre <lamarre_arch at yahoo.com>; Karen Walkerman <
> kwalkerman at gmail.com>;
> *Sent:* Tue, July 27, 2010 12:57:21 PM
> *Subject:* RE: [Equest-users] Demand Controlled Ventilation and EA Credit
> 1
>
> “Each model that I've done for LEED utilizes the same ventilation rates
> between the proposed and design; whether it was ASHRAE 62.1 or IMC 2003;
> however, the occupancy schedules changed in spaces where DCV was installed.”
>
>
>
> Ron, that’s an interesting statement in itself – modifying occupancy
> schedules has an impact on the mechanical cooling (not just the cooling
> associated with reduced ventilation air), which isn’t really fair.  Was that
> approved by GBCI?  If so, I guess it’s further proof that there is still a
> lot of inconsistency in the review of EAc1.
>
>
>
> Karen, I think your letter does a good job of requesting an official
> “ruling” from the USGBC.
>
>
>
> *GHT Limited
> **James Hansen, PE, LEED AP*
>
> *Senior Associate*
>
> 1010 N. Glebe Rd, Suite 200
>
> Arlington, VA  22201-4749
>
> 703-338-5754 (Cell)
>
> 703-243-1200 (Office)
>
> 703-276-1376 (Fax)
>
> www.ghtltd.com
>
> * *
>
>
>  ------------------------------
>
> *From:* Karen Walkerman <kwalkerman at gmail.com>
> *To:* equest-users <equest-users at lists.onebuilding.org>
> *Sent:* Tue, July 27, 2010 12:10:27 PM
> *Subject:* [Equest-users] Demand Controlled Ventilation and EA Credit 1
>
> All,
>
>
>
> below is a draft letter to the EA Credit 1 TAG chair.  I welcome any edits,
> or critiques, and if anyone would like to be a co-signer of the letter,
> please let me know.
>
>
>
> Thanks,
>
>
>
> --
>
> Karen
>
>
>
>
>
> It has come to our attention from a posting on the eQuest list-serve that a
> fellow energy-modeling professional has been asked to model proposed design
> and baseline design ventilation rates differently where the proposed design
> model utilizes demand controlled ventilation.  We have searched the ASHRAE
> 90.1 documentation as well as the LEED reference documentation and
> consistently find the requirement that baseline ventilation rates be modeled
> the same as the proposed design, and that credit can be taken for demand
> controlled ventilation.
>
>
>
> We understand that large energy savings can be gained from demand
> controlled ventilation and that in certain cases, 'gaming' of the system
> could result in abnormally high ventilation rates for the baseline design,
> while the DCV system keeps ventilation rates low in the proposed design,
> however, our main concern is that energy modelers are being made aware of
> changes to guidelines during the design review process.  At this stage, the
> energy modeler has already completed a significant amount of work in
> preparing the proposed and baseline design energy models, and all associated
> documentation.  Changing the baseline design ventilation rates requires
> re-modeling of the building and increases the likelihood that the project
> will have to challenge a 'rejected' result if the LEED reviewer is not
> satisfied with the energy modeler's response and modeling changes.
>
>
>
> We feel that it may be time to develop modeling guidelines for demand
> controlled ventilation, and that these guidelines should be developed,
> released, and required in a similar fashion to the district energy
> guidelines published by LEED for NC 2.2  Furthermore, we feel that any
> changes made to EA Credit 1 energy modeling guidelines should be made with
> adequate notice to the energy modeling community.
>
>
>
> Thank you for your consideration on this issue,
>
>
>
> --
>
> Karen Walkerman
>
> Second Law
>
>
>
>
>
>
>  ------------------------------
>
> The information contained in this communication is confidential, may be
> privileged, and is intended only for the use of the addressee.  It is the
> property of GHT Limited.  Unauthorized use, disclosure or copying of this
> communication or any part thereof is strictly prohibited and may be
> unlawful.  If you have received this communication in error, please notify
> me immediately by return e-mail or by e-mail to ght at ghtltd.com, and
> destroy this communication and all copies thereof, including all
> attachments.  Thank you.
>
>
>  ------------------------------
>
> The information contained in this communication is confidential, may be
> privileged, and is intended only for the use of the addressee.  It is the
> property of GHT Limited.  Unauthorized use, disclosure or copying of this
> communication or any part thereof is strictly prohibited and may be
> unlawful.  If you have received this communication in error, please notify
> me immediately by return e-mail or by e-mail to ght at ghtltd.com, and
> destroy this communication and all copies thereof, including all
> attachments.  Thank you.
>



-- 
Carol Gardner PE
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