[Bldg-sim] simulation software

Steve Playo splayo at phyinc.com
Tue Dec 18 09:02:31 PST 2007


Hello Ardas, hello to the Bldg-sim community. 

Short answer: Go with TRACE.

Longer response: 

Ardas, I'm afraid you have given me the opportunity I've been holding back
on, to give my two-cents on the "eQuest or not eQuest" question.  As you can
see below, that two-cents has ballooned into several thousand dollars of
thoughts (ha!) but I want to make sure I detail may answers in the hopes it
minimizes any offense taken to those who love eQuest.

I am an engineer working for a consulting firm in Philadelphia.  We have
been fortunate to land several large projects, of which some level of LEED
certification is being sought for each.  I have my LEED AP certification,
and have worked as an energy analyst and LEED professional on several
projects already.  Beyond my engineering background, I also worked for many
years in the IT industry, and have experience in programming and application
integration and development.  Therefore, I am the lucky guy in this office
who was chosen to lead the effort in becoming proficient in energy
simulation and modeling software.  We use different software packages
depending on what is best suited for project needs.  When we began this
endeavor, we heard about eQuest back when it was in its early 3.x series
versions, not as far back as some on this board I know but still far back
enough to appreciate newer developments in the program.  

I describe all of the above so that you know my opinion here comes from
practical experience and hands-on application of not only eQuest, but other
software packages.  With that said: 

Do not use eQuest. Go for TRACE, ENERGY 10, Carrier's HAP, or get into the
Revit vanguard, but if you are coming into the eQuest package cold, you will
find it to be frustrating, unreliable, and above all, lacking in any real
support structure in the event you have questions. 

To elaborate: 

1)There is NO REAL SUPPORT for eQuest users. None. I know creating and
maintaining an open board like Bldg-Sim is a time-consuming, often thankless
tasks, so right off the bat I want to make it clear to those that have
worked hard to make this forum, and probably have some emotional attachment
to it - I applaud your effort and continue to check the board often for new
discussion threads, of which I find several very interesting.  However, what
is often discussed and replied to on the Bldg-sim board has NOTHING to do
with questions regarding the operation of eQuest.  As an example, recently
there was a lively thread regarding the application of ASHRAE's 90.1 Appdx G
rule, which requires the budget building model to rotate and average its
simulated energy performance.  Great discussion to all those involved, I
feel I learned a lot thru the back-and-forth.  However, that discussion had
nothing, or very little, to do with eQuest.  
eQuest has it's origins as a text-only, line-command programming code, and
the graphic user interface (GUI)you see and use is an attempt to simplify
using the code's simulation engine, to reach a wider audience of engineers
who were not proficient in direct coding.  In order to make the graphic
interface manageable, however, the developers had to make choices as to what
code aspects the graphic input screens would first be connected to, and what
would have to wait for later updates.  Ultimately, I think it will be
impossible to give the GUI the complete capabilities as direct coding. That
means if you needed to do something with a system sim that was not
represented in the GUI, you must go to the code directly - a daunting task
even for someone with coding experience, let alone and engineer who has no
background in it.  

Since eQuest is a freeware product (or is the proper term shareware? Not
sure...), it was attractive to engineers who did not want to spend a lot up
front to do simulations, and soon the "buzzword" of the eQuest name got
around, and owner reps and other non-tech entities began asking if their
engineers were using eQuest, we must validate with eQuest, how's that eQuest
model coming along, etc.  Of course firms wanted to get on the bandwagon,
and be able to say "sure, we use eQuest" to win projects. However, what that
left the engineer with was a freeware product that was very detailed even
with its GUI, required a large learning curve, and, since you didn't pay
anything for it, had no support line or real support structure to it.  Even
to this day, I am unaware of any bona-fide support resource.  What made
matters worse was that eQuest was constantly being updated, even the help
files.  Often you would go to a specific topic in the help file, only to
find "Under Construction" as the answer! I've been told that "question
packs" would be available, as in you could pay $400 or so for a set amount
of tech issues, but I am unaware if this has actually gotten off the ground.


When you purchase TRACE or any of the other retail packages, the upfront
cost is required I know, but you have then bought into a real support
structure where you can email or call with questions or problems with
simulation.  I can't stress how important that is.  When you get knee deep
in a building model for a multi-million dollar project, and get snagged on
some techie bug with outputs or software gliches, trust me you don't want
your only means of support to be a discussion forum, you want to call a
software support tech who is being paid to assist you. 

I have other points to this, but the email is getting long in the tooth.
The other points I will make brief and wait for any response: 

2)eQuest operation is frustrating.  If you have a model that can stay within
the Design Wizard mode, most inputs and code-related data is automatically
entered for you, and the sim run smoothly.  However, I have never had a
model which I could fully run in Wiz mode, always having to access the
Detailed Date Edit mode and go bit by bit thru all the inputs.  Very
frustrating.  Also, there are several inputs which are difficult to
understand, and, coupled with the lack of help file sections, become
mysteries.  And lack of user interface features becomes a pain.  For
example, eQuest offers a table-style list of data inputs for anything from
window data to air handler data, but you cannot do group edits easily such
as select a similar column of cells and change all values at once.
Simulation processing times can be long, and there is no option which
minimizes what is simulated.  Carrier's HAP program for example allows you
to pick and choose what reports are generated, and what simulations are
performed. eQuest just has one large output file with ten thousand pages.
Maybe there is someone out there who knows some shortcuts to these specific
problems - but that gets back to the support issue - I am now relying on
someone to take the time to explain things to me, and for my time on this
board I have seen many, many question go unanswered.

3)eQuest reports are unreliable.  This may be due to the extensive detailed
inputs that are required for most system comparisons, but the result remains
the same - often eQuest reports (generated thru the DDE mode) come back with
crazy values and conclusions, which are difficult to analyze.  I've also ran
the same report several times on a model that had no modifications applied,
and the results have come back differently. This may be a factor of eQuest's
continuous updates and bug fixes, but again, if you are responsible for
analyzing a multi-million dollar building for LEED's EAcr1-10, you don't
want to be staying up all night trying to decipher cryptic report results. 

I know eQuest has a lot of potential, and I have had some limited success in
running simple models.  The unfortunate reality is most models are not
simple, and when you enter into the "gaming" of what-ifs to see how
insulation levels affect performance, what would ice storage be like vs.
chilled water, how does daylight econ impact light loads, water-cooled
compressors on DX units and apply water-side economization, etc etc, then it
doesn't help if you've "heard" eQuest can do all these things, and have no
recourse to find out how it can be operated to do so.  The reality is there
are other very good, very capable simulation packages out there, that may
not have all the detail as eQuest, but at least can return valid results and
support their user base more effectively. 

I think in the final analysis, that the hype of eQuest's purported
capabilities has outpaced the practical reality of its true capabilities,
and we as engineers are stuck trying to connect the open ends.

Hope this helps, 

Steve Playo
PHY Engineers
215-592-1900

-----Original Message-----
From: bldg-sim-bounces at lists.onebuilding.org
[mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Ardas
Sabuncuyan
Sent: Tuesday, December 18, 2007 10:41 AM
To: bldg-sim at lists.onebuilding.org
Subject: [Bldg-sim] simulation software

hi,

 we are planning to use EQUEST or TRACE 700 for energy simulation. 

 Is eQUEST an approved software by USGBC (in Texas)?

Where can we get training in DFW (Dallas Fort Worth) area?

 Which one is easier, faster? Trace 700 or eQUEST?

or do you know other simulation software (preferable free) that we can
utilize in our LEED design projects and we can get training in DFW area?

thanks

Ardas

 
 
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