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<p class=MsoNormal><span style='color:#1F497D'>Eric and everyone,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I think we’re all in general
agreement here – I’ve been tasked with developing existing models
to match historical consumptions to varying deadbands of accuracy – but
never with a prescriptive mandate. The targeted degree of calibration for
any of my projects is both selected by myself and varies, and for a variety of
reasons – primarily (1) time allowed to develop the model, (2) the information
available/obtainable, (3) the perceived accuracy of that information. <o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I don’t disagree: Tight
levels of matched historical data may not reflect a more sophisticated and
accurate model, especially for “predicitive” purposes, but until we
get a time travel feature added to the Wizards (come on dev team, get moving! ^_^)
– what is the alternative metric for modeling accuracy?<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>My statement that you quoted
wasn’t properly elaborated on my end, and I apologize for writing in
haste (end of the workday) – I don’t mean to suggest 1-2% is “good”
and anything higher is “bad,” or anything of that nature. More
directly: I simply mean to state that setting a target of monthly utility
consumption accuracy (either for yourself as the modeler or for another), is
entirely reasonable if the modeler is given the time and resources to continue
learning and investigating the building until such “historical accuracy”
is obtained. I personally, given no other direction, consider +/-10% (for
each utility and each modeled month) to be a minimum before results are
share-able.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I also want to emphasize: “Predictive
modeling” as a concept is a potential <u>minefield</u>, both for design
teams and building owners if and when it is (often) misunderstood. I’m
no professional orator/writer, so I don’t know if there is better existing
vocabulary for this, but I forcefully insist on keeping the distinction between
“predictive” and “historical” accuracy understood by
all parties and at all stages whenever I am interacting with others over
modeling projects.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>To respond to your hypothetical –
If I am in a project and I find the monthly consumptions are generally ~6% off,
where a target of 2% has been chosen by myself or others, my first reaction
would not be to arbitrarily tweak unknown assumptions to make the number “work.”
When I do this sort of project, I understand a myriad of assumptions have to be
made. In my mind, some assumptions are more of a “leap” than
others, so I keep a running list of those larger assumptions in a notepad at my
desk for future reference. Perhaps I never gathered information regarding
a specific roof retrofit’s construction, or I haven’t investigated
whether there are a separate set of setback conditions for a given school
season. When the time comes to calibrate the model, after ensuring
everything is entered as I intended, I then proceed to investigate further (ask
questions, make another site visit if necessary) as required to resolve the
items in my list to the best of my ability. Nothing is altered purely for
the purpose of “matching the numbers,” only in the name of
improving the model’s historical accuracy.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>If a deadline should arrive
someday where the targeted level of calibration is not met (hasn’t happened
yet – but then I’ve set my own targets…), I’ll rest
easy knowing I’ve developed the most accurate model I can with the time
and resources available to me. I also be ready to discuss at length the
major assumptions made and actions taken to address those unknowns.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Off the record, I’ve
approached +/- 2% within each monthly utility record consumption one (1) time,
and I had to become intimately familiar with the project over months to get
there. Much discussion with the building maintenance crew, site visits, and
poring over record documents was required. I fully agree this is not a
level of calibration that ought to be required except when an exceptional level
of time and resources are dedicated to investigating the building (at least for
a modeler with only a few years experience). If you were to look at a “predictive
accuracy gained : time/money spent developing the model” ratio, I’m
sure for most projects you would find sharply diminishing returns trying to
approach such a deadband. If there is a metric to measure “predictive
accuracy” for any model better than calibrating to historical data, I’d
love to learn about it, but to my knowledge it’s all we’ve got to
work with.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>That I’m writing such lengthy
responses hopefully conveys – this is a kinda tough topic to discuss!
I’m not trying to make any legally binding statements here, so please don’t
read between the lines – if anything I’m writing is clear as mud, I’ll
be happy to elaborate, time permitting =).<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Thanks,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>~Nick<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><img width=119 height=37
id="_x0000_i1030" src="cid:image001.jpg@01CB0E02.47D29E60"
alt="cid:489575314@22072009-0ABB"></span><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p> </o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'>NICK CATON, E.I.T.</span></b><b><span style='font-size:12.0pt;
font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><span style='font-size:7.5pt;color:#CC9900'>PROJECT ENGINEER</span><span
style='font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>25501 west
valley parkway<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>olathe ks 66061<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>direct 913
344.0036<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>fax 913
345.0617<o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;color:#2D4D5E'>Check out
our new web-site @ </span></i><span style='color:#1F497D'><a
href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span
style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;color:blue'> </span></u><span style='color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal><span style='color:#1F497D'><img border=0 width=119
height=37 id="Picture_x0020_1" src="cid:image001.jpg@01CB0E02.47D29E60"
alt="cid:489575314@22072009-0ABB"></span><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p> </o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'>NICK CATON, E.I.T.</span></b><b><span style='font-size:12.0pt;
font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><span style='font-size:7.5pt;color:#CC9900'>PROJECT ENGINEER</span><span
style='font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>25501 west
valley parkway<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>olathe ks 66061<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>direct 913
344.0036<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>fax 913
345.0617<o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;color:#2D4D5E'>Check out
our new web-site @ </span></i><span style='color:#1F497D'><a
href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span
style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;color:blue'> </span></u><span style='color:#1F497D'><o:p></o:p></span></p>
</div>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Eric O'Neill
[mailto:elo@MichaelsEngineering.com] <br>
<b>Sent:</b> Thursday, June 17, 2010 9:32 AM<br>
<b>To:</b> Li, Lan; Nick Caton; David Bastow; aazhari@jainconsultants.com;
equest-users@lists.onebuilding.org<br>
<b>Subject:</b> RE: [Equest-users] Actual Building Energy Cost<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='color:#1F497D'>Lan,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>That’s a good example.
I’m always amazed at the number of outside air dampers that are
broken/disconnected, have broken actuators, or crummy seals. A significant
percentage of existing buildings (and new ones for that matter!) have that
problem. It would be great if we had the time and budget to test all the
systems to find problems like this, but then we’re doing
retrocommissioning on top of energy modeling. And even then, our data is only
as good as the meters and the people placing them (is your mixed air
temperature logger – with an error of 2-3% - just a single logger ziptied
right in the middle of the airstream, potentially missing stratification?).<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Sorry, I’m done ranting </span><span
style='font-family:Wingdings;color:#1F497D'>J</span><span style='color:#1F497D'>.
Just some pent up frustration from being asked to do things that really
don’t make sense to me. I get the heebie-jeebies even thinking about
calibrating a model to an existing building, let alone to within 1-2%.
I’m just hoping someone will tell me that I’m being too academic
and that these things work themselves out in the real world. The DOE must have
good reason to request calibration within 1-2% other than a warm fuzzy feeling
when they get results, right?<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Eric<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> Li, Lan [mailto:lli@sbmce.com] <br>
<b>Sent:</b> Thursday, June 17, 2010 8:53 AM<br>
<b>To:</b> Eric O'Neill; Nick Caton; David Bastow; aazhari@jainconsultants.com;
equest-users@lists.onebuilding.org<br>
<b>Subject:</b> RE: [Equest-users] Actual Building Energy Cost<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>In one of
my learning course, the instructor mentioned that after they used eQuest
simulated an existing campus, they were not able to have the simulation results
to match utility bills close enough. It turned out that the economizer damper
was on all the time and the some meters were set up wrong which leads the
historical data was inaccurate. <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>Lan <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal style='margin-left:.5in'><b><span style='color:blue'>Lan Li,
PE<o:p></o:p></span></b></p>
<p class=MsoNormal style='margin-left:.5in'><b><span style='font-family:"Clarendon Cd";
color:#7030A0'>Mechanical Engineer</span></b><span style='color:#7030A0'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Clarendon Cd";
color:blue'>Scheeser Buckley Mayfield LLC
</span><span style='font-size:10.0pt;font-family:"Clarendon Cd";color:blue'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>1540
Corporate Woods Parkway</span><span style='font-family:"Clarendon Cd";
color:blue'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Clarendon Cd";
color:blue'>Uniontown, OH 44685<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>Phone:
(330) 896-4664 ext. 123<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>Cell:
(330) 904-6292<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'>Fax: (330)
896-9180<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><u><span style='font-family:"Clarendon Cd";
color:blue'><a href="mailto:lli@sbmce.com" title="blocked::mailto:lli@sbmce.com"><span
style='font-family:"Calibri","sans-serif"'>lli@sbmce.com</span></a></span></u><span
style='font-family:"Clarendon Cd";color:blue'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:blue'><a
href="http://www.sbmce.com/"
title="blocked::http://www.sbmce.com/
http://www.sbmce.com/">www.sbmce.com</a><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='color:blue'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Clarendon Cd";
color:blue'>Columbus Branch Office (614) 448-1498<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='font-family:"Arial Narrow","sans-serif";
color:navy'> </span><span style='font-size:10.0pt;font-family:"Arial Narrow","sans-serif";
color:#008040'>Please consider the environment before printing this email.</span><span
style='font-family:"Clarendon Cd";color:#008040'><o:p></o:p></span></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
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<p class=MsoNormal style='margin-left:.5in'><span style='font-size:7.5pt;
color:#008040'>Thank you<o:p></o:p></span></p>
</div>
<div>
<div style='margin-left:.5in'>
<div class=MsoNormal align=center style='text-align:center'><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'>
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<p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> Eric O'Neill
[mailto:elo@MichaelsEngineering.com] <br>
<b>Sent:</b> Thursday, June 17, 2010 8:11 AM<br>
<b>To:</b> Nick Caton; David Bastow; aazhari@jainconsultants.com;
equest-users@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Equest-users] Actual Building Energy Cost</span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
</div>
<p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>Nick,<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>I
should make it clear that my initial questions weren’t meant to drill
David. I’m genuinely interested if the DOE projects required an extremely
high level of technical accuracy on the input side. (Although they were also
somewhat of a reaction to those requirements.) We have this discussion in our
office every so often, and I’m usually somewhat on my own, but I’m
still not convinced.<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>Would
you mind elaborating a little more about why you feel this to be true:<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>“HOWEVER:
The concept of building a model for an existing building, whose modeled energy
consumption/costs fall within a 1-2% of historical utility records, is entirely
feasible – and a reasonable requirement if the goal is to generate a
model for predictive purposes.” <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>So let
me ask it this way. Let’s say you’ve got a model, and it’s
coming in about 6% low (both heating and electric), but to the best of your
knowledge everything is set up properly. You’ve got to start making some
educated guesses to close the gap. Do you assume the boiler needs a tuning
(drop your efficiency a few percent) and the AHU coils need to be cleaned (bump
up your static)? Or do you bump up your infiltration slightly (because
it’s probably not a very tight building). Or did some maintenance guy
came along and switched on both the boiler pump manually on when he got a cold
complaint, and no one returned them to auto? Or maybe you have data from a few
years with abnormally warm summers and cold winters. I could go on practically
ad nauseum. There’s just so many things that can be wrong with an
existing building, as all of you probably know.<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>Whatever
you choose, that guess you make may interact (or lack an interaction) with some
measures you’re predicting. So, predicatively, what makes a 1-2% off
model better than a 5-6% off model unless you really spend the time and find
out whether your inputs are accurate? <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>Cheers,<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'>Eric<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='margin-left:1.0in'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> Nick Caton [mailto:ncaton@smithboucher.com]
<br>
<b>Sent:</b> Wednesday, June 16, 2010 5:43 PM<br>
<b>To:</b> Eric O'Neill; David Bastow; aazhari@jainconsultants.com;
equest-users@lists.onebuilding.org<br>
<b>Subject:</b> RE: [Equest-users] Actual Building Energy Cost<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal style='margin-left:1.0in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>While
I (and I am sure many others) have books to write regarding my thoughts on the
topic, I think I might suggest a simple step back: The concept of <u>predictively</u>
modeling to within a few percentage points of accuracy is ridiculous.
There are simply way to many things that could not be known.
HOWEVER: The concept of building a model for an existing building,
whose modeled energy consumption/costs fall within a 1-2% of historical utility
records, is entirely feasible – and a reasonable requirement if the goal
is to generate a model for predictive purposes. How often such predictive
models’ accuracy is misinterpreted is something I get depressed to think
about.<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>I
haven’t done the DOE-modeling work that’s being referenced with
such requirements, but I have done work for educational clients
(physics/building science departments) who wish to get these models set up for
ongoing study/tweaking purposes. The exercise is challenging, and as
close as energy modeling gets to “fun,” when you can rest at ease
knowing the client is fully on board with what the model is and
isn’t. <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>It’s
fully rational to squirm and cringe when you have to make models that you know
will be mis-used and mis-understood, despite your best efforts. Fortunate
is the practicing energy modeler who gets to work for fully educated clients
and design teams all the time =).<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'> <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>Rather
than drill David, I think it would be safe to assume those DOE requirements
exist to calibrate a model to a given degree to whatever historical records are
available, NOT to mandate a level of accuracy for predictive purposes. If
I’m wrong, I hope that work never crosses my desk!<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>~Nick<o:p></o:p></span></p>
<div>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><img
border=0 width=119 height=37 id="_x0000_i1026"
src="cid:image001.jpg@01CB0E02.47D29E60" alt="cid:489575314@22072009-0ABB"></span><b><span
style='font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal style='margin-left:1.0in'><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p> </o:p></span></b></p>
<p class=MsoNormal style='margin-left:1.0in'><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'>NICK CATON, E.I.T.</span></b><b><span style='font-size:12.0pt;
font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='font-size:7.5pt;
color:#CC9900'>PROJECT ENGINEER</span><span style='font-size:7.5pt;font-family:
"Times New Roman","serif";color:#CC9900'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='font-size:10.0pt;
color:#2D4D5E'>25501 west valley parkway<o:p></o:p></span></p>
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color:#2D4D5E'>olathe ks 66061<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='font-size:10.0pt;
color:#2D4D5E'>direct 913 344.0036<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='font-size:10.0pt;
color:#2D4D5E'>fax 913 345.0617<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><i><span style='font-size:10.0pt;
color:#2D4D5E'>Check out our new web-site @ </span></i><span style='color:#1F497D'><a
href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span
style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;color:blue'> </span></u><span style='color:#1F497D'><o:p></o:p></span></p>
</div>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='margin-left:1.0in'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Eric
O'Neill<br>
<b>Sent:</b> Wednesday, June 16, 2010 4:52 PM<br>
<b>To:</b> David Bastow; aazhari@jainconsultants.com;
equest-users@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Equest-users] Actual Building Energy Cost<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal style='margin-left:1.0in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>How
much effort was put into minimizing the error of your inputs to justify that
level of accuracy in your output? For example, did you convert real weather
data for the two years and use an average of the simulations? Were you modeling
small buildings so you could get a fairly reasonable infiltration rate
empirically? Were occupancy schedules trended, and for how long? Were all the
systems and controls working correctly, with all sensors calibrated regularly? <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>1 to
2% seems to me to be fairly unreasonable. Unless you do an amazing job
verifying your inputs, in my opinion that level of precision doesn’t get
you a better model. If you set everything up as best you can and it comes in
there, great! But a correctly set up model can be off by over 2% because of a
couple “El Nino” years, a facilities guy locking a humidity high
limit to 50% for a summer, or any number of operational factors. On the other
side of it, we’ve tried to match a simple DOE2.2 model to a DOE2.1e model
with limited success (I don’t think we got within 3%, although we didn’t
spend too much time with it). Who knows what the difference would be with E+.<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>I know
I always squirm when I’m asked to do existing building models, and it may
be irrational. Heck, if the DOE is asking for 1-2%, I probably am being
irrational. But it seems to me that the error from assumptions could easily
swing a model 1-2% (what would a 30% error on your infiltration do to an
otherwise correct building?). What are other people’s thoughts? <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'>Eric<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.0in'><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='margin-left:1.5in'><b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>David
Bastow<br>
<b>Sent:</b> Wednesday, June 16, 2010 3:48 PM<br>
<b>To:</b> aazhari@jainconsultants.com; equest-users@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Equest-users] Actual Building Energy Cost<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal style='margin-left:1.5in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:10.0pt;
font-family:"Arial","sans-serif";color:blue'>On all the DOE modeling
projects that we have done, of an existing building, they have required the
model to be within 1 to 2% or less of the actual energy usage, based on an
average two year history. Is that what you are talking about?</span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:12.0pt;
font-family:"Times New Roman","serif"'> <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><em><b><span style='font-size:
24.0pt;font-family:"Bradley Hand ITC","serif";color:blue'>David A. Bastow </span></b></em><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><em><b><span style='font-size:
12.0pt;font-family:"Rockwell Extra Bold","serif"'>McClure Engineering,
Inc. </span></b></em><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:12.0pt;
font-family:"Times New Roman","serif"'> <o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:12.0pt;
font-family:"Times New Roman","serif"'><o:p> </o:p></span></p>
<div style='margin-left:.5in'>
<div style='margin-left:.5in'>
<div style='margin-left:.5in'>
<div class=MsoNormal align=center style='text-align:center'><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'>
<hr size=2 width="100%" align=center>
</span></div>
</div>
</div>
</div>
<p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:
12.0pt;margin-left:1.5in'><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
equest-users-bounces@lists.onebuilding.org
[mailto:equest-users-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Ahmed
Azhari<br>
<b>Sent:</b> Wednesday, June 16, 2010 12:10 PM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> [Equest-users] Actual Building Energy Cost</span><span
style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'>Hi all, <o:p></o:p></p>
<p class=MsoNormal style='margin-left:1.5in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:1.5in'>Does anyone have a ballpark
percentage of the <b>actual</b> annual energy cost versus the <b>modeled</b>
annual energy cost for a building? <o:p></o:p></p>
<p class=MsoNormal style='margin-left:1.5in'><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:1.5in'>Thanks,<o:p></o:p></p>
<p class=MsoNormal style='margin-left:1.5in'><span lang=EN-CA style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:black'>__________________________________________________________________________</span><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:12.0pt;
color:#0F243E'>Ahmed Azhari</span><span style='font-size:12.0pt;color:#002060'>,
</span><span style='font-size:10.0pt;color:gray'>B.Eng., LEED® AP</span><span
style='font-size:12.0pt;color:#002060'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:10.0pt;
color:gray'>Energy Analyst<o:p></o:p></span></p>
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color:gray'><o:p> </o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='color:#0F243E'>Jain
Sustainability Consultants Inc.<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='color:#002060'><o:p> </o:p></span></p>
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color:gray'>2260 Argentia Road, 2nd Floor<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:10.0pt;
color:gray'>Mississauga, Ontario L5N 6H7, CANADA<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:10.0pt;
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<p class=MsoNormal style='margin-left:1.5in'><span style='font-size:10.0pt;
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