[Equest-users] equest and energy plus outputs

Thu Apr 28 14:55:09 PDT 2011

This was a little study I did out of curiosity last year, and the
results between eQUEST (v3.63) and EnergyPlus (v4.0) matched quite well
(~1.4% difference). All the schedules, zone areas, surface areas were
exactly the same (I checked), but I also chose a simple system; PTAC
units for the comparison. I believe when I was doing this I had checked
the performance curves that were being used in EnergyPlus and they
matched the eQUEST curves. 

I assume the results will begin to differ when the systems become more
complicated, but even then I believe if both models are calibrated to
match as much as possible the results shouldn't vary significantly
(assuming all systems are native to the programs and we're not creating
work-arounds i.e. DOAS in eQUEST using dummy zones or the like).

(FYI, the geometry was ported over to EnergyPlus through a tool I wrote
using Excel and VBA, but it's a messy process)

Following are some of the results and graphical outputs:

____________________

Mirza Sajjal
Engineer

Buro Happold
100 Broadway
New York, NY 10005

Tel: +1 212 334 2025

Direct: +1 212 616 0380

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Pasha
Korber-Gonzalez
Sent: Thursday, April 28, 2011 4:46 PM
To: deepika khowal
Cc: equest-users at lists.onebuilding.org; energyplus_support
Subject: Re: [Equest-users] equest and energy plus outputs

As I understand it--Energy+ is free-ware in it's raw form.    I guess I
was wrong to make an assumption that Deepika is using it without an
interface.    If this is not the case it might explain such a variance
in results.     When I model in DOE-2 raw form---it is so much harder
for me to manage my data and inputs in my head and such----I was not
born to be a programmer, and it gives me nightmares from struggling to
pass FORTRAN so many years ago...ugh.

Therefore, I haven't looked at E+ myself for a very long time and
purchasing or putting out the cost for the user-interface programs is
not as desireable as using the eQuest free-ware.  or the future CANQuest
free-ware (future SI version).

BUT-- I know that E+ is supposed to have some great capabilities in
which we are limited with DOE-2 (to an extent.)    Has anyone else had
the time and desire to compare these program engines more closely
recently?   Also--why is it so difficult to "match" systems in eQuest
and E+....forgive my blase'-ness, but isn't a pkgd system a pkgd
system...a pkgd system???  :)

Pasha 

On Thu, Apr 28, 2011 at 11:39 AM, deepika khowal <
deepika.khowal at gmail.com> wrote:

So based on my analysis, there is a difference of about 10% in results
of equest and E+. I would believe that because there are certain
parameters which are very difficult to match. 

this seems reasonable to me. 

On Thu, Apr 28, 2011 at 9:09 AM, John Aulbach <jra_sac at yahoo.com> wrote:

I am sure EnergyPlus is a fine and well thought out program (consider
the sources and fine people involved).  However, since I am in
production mode (and don't have time to create a model in two different
programs-who pays for THAT), I chose to migrate to eQuest after DOE-2.1
A, B, C, D, and E. There are plenty of resources to ask questions of,
the program started out in Windows (didn't need "add ons"), and gives me
a 3-D rendering on the building immediately.

I dealt with 20 years of "raw" DOE-2, where I didn't know what my
building really looked like (until Joe Huang came along with BDL
Draw..). So I would need at age (you guess..) to not relearn an entirely
new program and stick with what I had learned over the past 25+ years.

John R. Aulbach, PE, CEM

Senior Energy Engineer

________________________________

Partner Energy

1990 E. Grand Avenue, El Segundo, CA 90245
W: 888-826-1216, X254| D: 310-765-7295 | F: 310-817-2745

www.ptrenergy.com <http://www.ptrenergy.com/>  | jaulbach at ptrenergy.com
<mailto:%7C%20jaulbach at ptrenergy.com> 

________________________________

From: deepika khowal <deepika.khowal at gmail.com>
To: Paul Diglio <paul.diglio at sbcglobal.net>
Cc: equest-users at lists.onebuilding.org; energyplus_support <
EnergyPlus_Support at yahoogroups.com>
Sent: Thu, April 28, 2011 8:56:34 AM 

Subject: Re: [Equest-users] equest and energy plus outputs

As Joe and others mentioned, its really difficult to create all
parameters same in both softwares. 

I am still working on it .

For ex, which system should I use in equest as equivalent to unitary
system in E+?

I understand its difficult to match every input and hence, getting same
results is very tricky.

Thanks all for their inputs

On Thu, Apr 28, 2011 at 4:54 AM, Paul Diglio <paul.diglio at sbcglobal.net>
wrote:

I thought E+ is a free program?  I would be interested to hear from
anyone who has used Google SketchUp and the Open Studio Plug-in to
generate a 3D view in E+.

I would like to hear more about the discrepancies between eQuest and E+
from those who use both programs.

Paul Diglio

________________________________

From: Pasha Korber-Gonzalez <pasha.pkconsulting at gmail.com>
To: deepika khowal <deepika.khowal at gmail.com>
Cc: energyplus_support <EnergyPlus_Support at yahoogroups.com>; 
equest-users at lists.onebuilding.org
Sent: Thu, April 28, 2011 1:27:44 AM
Subject: Re: [Equest-users] equest and energy plus outputs

Hmmm- an energy plus model showed 50% less energy use (EUI) than eQuest?
Did you use the same weather files?  (i.e. convert the EPW you used in
E+ to .bin and use the same weather file in eQuest?)

If this is truly the case, this is unsettling as a simulator.   Wouldn't
it be safer for our clients to error on the conservative side and give
the eQuest results instead of the E+ results?

Also--if this is the case, then what is the market advantage to spending
thousands of dollars on E+ software rather than use the FREE-ware eQuest
program??

I'd appreciate any commentary to help me "see the light" of this topic.
And if Deepika is willing to share a visual of his energy results
output, I'm super curious to see what it is showing...

Good question/good info...thanks,

Pasha

Korber Energy Consultants

On Wed, Apr 27, 2011 at 7:11 PM, deepika khowal <
deepika.khowal at gmail.com> wrote:

Thanks Joe 

Even I realized the same thing. the total energy use in Energy plus was
almost 50% less than equest.

If this is the case, who would you know that you model is working fine? 

On Wed, Apr 27, 2011 at 6:06 PM, Joe Huang <
yjhuang at whiteboxtechnologies.com> wrote:

I was involved in a two year project 2005-2007 to convert the Calif.
Energy Commission's Title-24 certification suite of building tests from
DOE-2.1E to EnergyPlus.  There are some areas where it's difficult to
get comparable inputs due to differences or limitations in the models.
The differences between the two programs varied a lot depending on the
building, weather, and HVAC system. For the CEC certification suite of
160 runs, cooling results were more consistent, within 10% in most
cases, with EnergyPlus almost always on the high side; for heating, the
differences were much greater, sometimes with EnergyPlus being 40-60%
lower than DOE-2.1E.  I have a 120-page report on this comparison, but
haven't bothered to put it on the Web.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 108D
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
www.whiteboxtechnologies.com <http://www.whiteboxtechnologies.com/> 
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"

deepika khowal wrote:

HI All
I am trying to create same model in equest and energy plus to see
whether i see same results and just to validate my simulation files.
has anyone done this before?
I would like to know what is the % difference in both software outputs?
Thanks
Deepika

------------------------------------------------------------------------

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to 
EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to 
EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to 
EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG

This message has been scanned by MailController -
portal1.mailcontroller.co.uk | 

This message has been scanned by MailController
<http://portal1.mailcontroller.co.uk/> .

This message has been scanned by MailController - portal1.mailcontroller.co.uk
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 52713 bytes
Desc: image005.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 22695 bytes
Desc: image006.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0001.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 12136 bytes
Desc: image008.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0002.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 10595 bytes
Desc: image010.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0003.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 10289 bytes
Desc: image012.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0004.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 18621 bytes
Desc: image014.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0005.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 33966 bytes
Desc: image016.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0006.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 53001 bytes
Desc: image026.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0007.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 75984 bytes
Desc: image027.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110428/66694e8d/attachment-0008.jpeg>