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Hello Everyone,

I am trying to finalize a building model for a LEED submission but am having difficulty getting the BEPS report "percent of hours any system zone outside of throttling range" to match the SS-R reports "zone under heated" and "zone under cooled" hours. This was a complaint from the LEED reviewer.

The building has three systems and all spaces are conditioned. The BEPS report lists hours outside of throttling range at 2% (175hrs), but the SS-R report lists under heated and cooled hours of 280 (3.2%).

I consider myself fairly familiar with equest but am unable to get these two numbers to match. Has anyone run into this problem in the past or have any ideas of where I should be focusing my attention?

Many Thanks,

Andrew McMurray, EIT

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Joined: 2011-09-30
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There's much discussion on this in the archives, but basically the
difference is that BEPS/BEPU is reporting % of coincidental unmet hours
(when multiplied by the annual hours fans on in report SS-E), as we
intuitively think of it, whereas the SS-R reports are reporting unmet
hours for each zone without regard to coincidental unmet hours. Summing
the SS-R reports may be the more intuitive approach, but you'll end up
with a conceptually different figure that can often be higher than the
figure found through BEPS/SS-R.

Note there's a degree of rounding involved when you only get a
percentage to so many decimal places.

As an example, if you had an imaginary model with only two zones which
were unmet all year long, BEPS would report 100% hours outside
throttling range, whereas adding up the SS-R report hours might lead you
to believe there are as many as 8,760*2 = 17,520 hours per year.

Therein lies the answer to why the numbers don't sync up after adding up
the SS-R figures. For now, multiplying the BEPS figure by the annual
hours fans on is the best approach imho for documenting compliance with
the baseline/proposed unmet hours requirements.

It's been said the next released version of eQuest will present this
information more clearly in the BEPS/BEPU reports.

NICK CATON, E.I.T.

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Andrew,

I would write a narrative explaining how eQUEST calculates unmet hours.
You take the % of hours outside throttling range on your BEPS or BEPU
report and multiply it by the number of hours your fan is on (SS-E
report).

The SS-R report shows room-by-room unmet hours. You should not take the
sum of these hours because 10 rooms may be unmet at 3:00-5:00 and the
BEPS report calculates this as 2 hours while the sum of the SS-R report
calculates it as 20 hours (10 rooms x 2 hours).

Otto

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Joined: 2011-09-30
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Hi all,

It's my 1st time to use eQUEST and have this question:

It seems the program always use Title 24 as the baseline. How can we
incorporate ASHRAE 90.1 requirements into eQUEST ?

The following is my understanding and not quite sure if it's right or
not:

First we need to setup a baseline based on ASHRAE 90.1, create a design
case, then how can we force the program to compare the design case with
the ASHRAE 90.1 baseline case, instead of the Title 24 baseline case ?

Any advice ?

Thanks,

Derek Huang, LEED AP, CPD

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Hi Derek,

Performing a 90.1 Baseline/Proposed comparison with eQuest will require
building two models. There are many way to skin the cat, but common
practice is to build up either your baseline or proposed model, save a
copy right before transitioning to detailed mode from the wizards,
finish the model in detailed, then use the wizard-level and final models
as references to build the second model.

I personally find starting with Proposed (instead of the 90.1 Baseline)
to be easier than the other way around, having tried both, but opinions
differ. You may want your 90.1 baseline model created first depending
on where your modeling starts in relation to the design process.

I've copied a discussion from this list below that includes others'
views and some more specifics. You can find more discussion through the
archives - feel free to ask specific questions if you need to!

http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/

http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/

NICK CATON, E.I.T.

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Dear all,

I was wondering how to model Fan Coil Units in eQUEST.

I understand that when you create an air-side HVAC system, this is the Air Handling Unit, and then the zones under the AHU are the spaces served by this AHU. Is my understanding right?

Many thanks,

Omar Katanani

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Basically yes.
Bruce

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It might help Omar and a number of recent question-posters to recognize the term "fan coil unit" is used outside of eQuest to describe a variety of real-world equipment. In eQuest, Fan coil units (system type FC) are a very specific system - in my mind, this is analogous to what I'm used to calling a "PTAC" - a wall/window unit typically used in hotels and small classrooms to provide single-zone conditioning (link ). That doesn't sound quite like the central AHU system you're describing...

One can occasionally avoid a major personal headache in the long term by perusing the DOE2 help file system descriptions before modeling any specific system for the first time - I speak from personal experience! Here's where to look...

Click Help ? DOE-2 Help... and check out:

Volume 1 ? Air-side Components ? HVAC Air SYSTEM Types

and

Volume 3 ? Air-side System Types

NICK CATON, E.I.T.

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Hi all,

I finished the Parametric Run but didn't see any percentage of dollar
savings from the Annual Building Summary. Does anyone know where it is ?
LEED certification needs this number.

Thanks,

Derek Huang, LEED AP, CPD

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Derek,

You can get the baseline and proposed $/yr from the ES-D report and
calculate the % saved using (Baseline $/yr - Proposed $/yr)/Baseline $/yr

Carol

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Hello

I have several questions on working with E-quest.
1. is it in any way possible to predict PMV's in the building, by use of the mean radiant temperatures of the room surfaces?
2. in the betailed simulation output, I could find the building heating loads, and their split-up in conduction, gain, solar etc. The house I'm modelling has some rooms set on 59 degrees and others on 68 degrees F. Therefore, the total yearly internal conduction is high (35 GJ), which also affects the total heating demand (about 50GJ). One would expect that the conduction through internal walls would not add up to the total heating demand of the whole house. Why is this high value taken into the sum? Could it be left out?

Many thanks,
Filique

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What if there are a number of different fan schedules in the
building? Do you multiply the 2% from BEPS for all systems? What if
only one zone on one system has unmet hours - how do you use the BEPS
report to calculate which zone and for how many hours?

It seems to me that the SS-R report provides the most useful
information for determining which systems/zones are under heated/cooled.

In Andrew's case, I believe the reviewer is off his/hers rocker -
asking that the SS-R and BEPS report match.

Chris Jones

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To all:

I am trying to model an outdoor park lot that has outside lights. How do I
add the lights to my building model?

Thank you.

Yehuda Israel,

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you'll have to add them as exterior ltg load or process load (kW) and assign
an operating schedule to them so that you can track when they are on and off
(fractional schedule).

Since this type of energy load has no impact on the thermal conditioning and
operation of your building itself, it is considered an ancillary or
'process' type load associated with the building that you are modeling.

Pasha

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Joined: 2011-09-30
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Just to add a couple of things:

1. You model it as a direct load on to the electric meter

2. You can create (in the newer versions of eQUEST) a schedule controlled by a photo sensor to turn the lights off when there is daylight.

Vikram Sami, LEED AP

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Thank you for your help.

I am currently working in the SD Wizard. How do I model it as a direct load
on the electric meter? As I understand it, every load must be attached to
an area allocation.

Thank you,

Yehuda

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Yehuda,

If you are in the DD wizard, you can enter exterior lighting on Screen 23 of the building shell screens. The area for the watts per square foot is the interior building floor area, not any exterior surface area.

If you are in the Detailed Interface, click on "Utility & Economics" in the upper right. In the Component Tree list on the left side of the screen, select "Electric Meters." At the top of the screen, select the Display Mode to be "Electric Meter - Direct Loads - Exterior." Here you can enter the exterior lighting loads in kW (instead of W/sf like in the wizard).

Keith Swartz, P.E., LEED AP

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You may need to be in the DD wizard to do this. The project I have open
is beyond the SD. Finish all your basic setup in the SD wizard for the
first floor and change to DD wizard. Use a copy and nothing is lost. I
will stay for hours or days at the finish button of the Project
Navigator in the DD wizard doing incremental edits, saving each time.
Each time you press finish your project is run, confirming equest is
happy with your changes. In building shell, using the action tab
select, building creation wizard, and it will bring up the project
navigator after a warning about losing everything you entered in
detailed edit. Be working with a copy and ignore the warning. Don't add
anything after this screen and you have nothing to lose. You can also
go back and forth as many times as you like. Select your Bldg Envelope
and Loads 1, that should be all you have coming from the SD wizard. To
add the Keith's post, you may need to go to screen 15 first, non-HVAC
End uses to Model, select exterior lighting, select mode. This will
turn on screen 23, go there next, set your W/sq.m and you profile
details. Note screen 15 is a gateway to adding many other options and
turning on other screens. If you are missing screens you need to go to
earlier pages and find the check box to open other screens you may wish
to add information on.
Bruce Easterbrook P.Eng.

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