<BODY contentEditable=true onload=parent.init()><P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>DOE2 and EnergyPlus<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></FONT></SPAN></B></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>I would like to see the results of DOE21E (or eQUEST / DOE22) and EnergyPlus compared with the following two projects.<SPAN style="mso-spacerun: yes"> </SPAN>They are similar to real projects but modified and simplified for teaching purposes.<o:p></o:p></FONT></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>Middle School & Community Center (150,000 sf approx.) <o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><A href="http://bepan.info/proj-bldgs/p12-middle-school"><FONT color=#0000ff face=Calibri>http://bepan.info/proj-bldgs/p12-middle-school</FONT></A><o:p></o:p></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>High-Rise - Multi-Use Building (1,000,000 sf approx.)<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><A href="http://bepan.info/proj-bldgs/p13-high-rise-bldg"><FONT color=#0000ff face=Calibri>http://bepan.info/proj-bldgs/p13-high-rise-bldg</FONT></A><o:p></o:p></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>Has a building of the size and scope of the 160-storey Burj-Dubai (Burj-Khalifa project analyzed by TRACE) been analyzed with EnergyPlus? See facts and figures<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><A href="http://www.burjkhalifa.ae/the-tower.aspx"><FONT color=#0000ff face=Calibri>http://www.burjkhalifa.ae/the-tower.aspx</FONT></A><o:p></o:p></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>How about a full university campus with one central plant?<o:p></o:p></FONT></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>In my opinion EnergyPlus needs to remove (or make optional) the features that increase execution time.<SPAN style="mso-spacerun: yes"> </SPAN>See attachment <B style="mso-bidi-font-weight: normal">USDOE Energy-Programs - DOE21E and EnergyPlus</B><o:p></o:p></FONT></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><FONT face=Calibri><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 12pt">Why should a private firm develop an interface to EnergyPlus after USDOE left all the developers of interfaces to the DOE21E stranded?</SPAN></B><SPAN style="FONT-SIZE: 12pt"><SPAN style="mso-spacerun: yes"> </SPAN>There is no money to be made from the engineering software business.<SPAN style="mso-spacerun: yes"> </SPAN>Development costs of graphics and forms interface costs are much higher than engineering analysis, but small compared to the marketing, support and training costs.<SPAN style="mso-spacerun: yes"> </SPAN>There are few customers for engineering software and they expect to pay about $50 to $500 which is typical of commercial software products.<o:p></o:p></SPAN></FONT></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt"><FONT face=Calibri>Varkie<o:p></o:p></FONT></SPAN></P>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>From <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><A href="mailto:"></A><A href="javascript:parent.addSender(%22Joe%20Huang%20%3cyjhuang@whiteboxtechnologies.com%3e%22)"><FONT color=#0000ff face=Calibri>Joe Huang <yjhuang@whiteboxtechnologies.com></FONT></A><FONT face=Calibri> <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD></TR>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>Thursday, April 28, 2011 8:12 pm<SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD></TR>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>To <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><A href="javascript:parent.addSender(%22Paul%20Diglio%20%3cpaul.diglio@sbcglobal.net%3e%22)"><FONT color=#0000ff face=Calibri>Paul Diglio <paul.diglio@sbcglobal.net></FONT></A><FONT face=Calibri> <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD></TR>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>Cc <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><A href="javascript:parent.addSender(%22energyplus_support%20%3cEnergyPlus_Support@yahoogroups.com%3e%22)"><FONT color=#0000ff face=Calibri>energyplus_support <EnergyPlus_Support@yahoogroups.com></FONT></A><FONT face=Calibri> , </FONT><A href="javascript:parent.addSender(%22%20equest-users@lists.onebuilding.org%22)"><FONT color=#0000ff face=Calibri>equest-users@lists.onebuilding.org</FONT></A><FONT face=Calibri> <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD></TR>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>Subject <SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD>
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<P style="MARGIN: 0in 0in 0pt" class=MsoNoSpacing><SPAN style="FONT-SIZE: 12pt; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin"><FONT face=Calibri>Re: [Equest-users] equest and energy plus outputs<SPAN style="COLOR: black"><o:p></o:p></SPAN></FONT></SPAN></P></TD></TR></TBODY></TABLE>
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<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><FONT face=Calibri><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt">I did not think my previous reply to Deepika would engender so much traffic on this topic, but after reading through the various posts I feel compelled to add further comments because I think there's been some misunderstanding or misperceptions about comparing results between two programs, in this case, specifically EnergyPlus and eQUEST or DOE-2:<BR><BR>1) Several people (some even in private e-mail) have mentioned looking at the BESTTEST or SP-140 test runs that are repeated everytime there's a new EnergyPlus release. <B style="mso-bidi-font-weight: normal">Those simulations are extremely simplified test cases, mostly of one-zone models designed to </B></SPAN><B style="mso-bidi-font-weight: normal"><SPAN style="LINE-HEIGHT: 115%; COLOR: #c00000; FONT-SIZE: 14pt">test fundamental heat transfer algorithms</SPAN></B>
<B style="mso-bidi-font-weight: normal"><SPAN style="LINE-HEIGHT: 115%; COLOR: #c00000; FONT-SIZE: 12pt"> </SPAN></B><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt">- the impact of solar gain, wall heat loss, thermal mass - across various programs. <B style="mso-bidi-font-weight: normal">These test cases do not begin to address the dynamic conditions found in any real building, particularly not a large commercial building. </B> Unfortunately, it's these interactions between the transient loads and the HVAC system response that will color or dominate the resultant energy numbers.<o:p></o:p></SPAN></FONT></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><BR><FONT face=Calibri>In my opinion, a far more revealing test suite would be either the CEC Title 24 certification test suite or even the ten DOE-2 sample runs, where the models are of realistic buildings with typical systems and operating controls (for more details on the Title-24 certification test <BR>suite, please see my SimBuild 2006 paper, available for download at <BR></FONT><A href="http://www.wbt/downloads/SimBuild2006_EPlusDOE2_translatorF.pdf" target=l><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>http://www.wbt/downloads/SimBuild2006_EPlusDOE2_translatorF.pdf</FONT></SPAN></A><FONT face=Calibri> ). <o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><FONT face=Calibri><B style="mso-bidi-font-weight: normal"><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt">My point is that the BESTTEST/SP140 results may show that the basic heat transfer algorithms in the programs are (reasonably) consistent, but that doesn't mean the programs will show similar results when used to model actual buildings, </SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN style="LINE-HEIGHT: 115%; COLOR: #c00000; FONT-SIZE: 14pt">particularly not commercial buildings with intermittent operations and complex HVAC systems and controls.</SPAN></B></FONT><SPAN style="LINE-HEIGHT: 115%; COLOR: #c00000; FONT-SIZE: 14pt"><BR></SPAN><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><BR><FONT face=Calibri>2) <B style="mso-bidi-font-weight: normal">Several people sounded incredulous that the differences could be as much as 50%.</B>
I can only say that if you try it, i.e., model the same building (preferably not a shoebox with a window on one side :-)) with two programs, you will quickly appreciate the difficulty. Actually, from my vantage point, <B style="mso-bidi-font-weight: normal">50% does not sound exaggerated at all</B>. I just got back from a simulation workshop in China, where differences of several hundred percent were reported comparing programs such as DOE-2.1E, TRNSYS, and DeST, a Chinese program, even though they were looking only at residential apartment buildings. The dirty secret in our field is that even </FONT><FONT face=Calibri><B style="mso-bidi-font-weight: normal">if you asked two reasonably competent modelers to model the same building with the same program, they're apt to come up with quite different results. Doing it with two different programs just makes that match exponentially more difficult.<BR></B><BR>
3) Several people (including me) have alluded to the difficulty in making the inputs consistent. I cannot emphasize this enough. <B style="mso-bidi-font-weight: normal">All programs have hundreds of hidden defaults or assumptions that aren't necessarily transferable</B>. My paper highlights nine of the most prominent ones found in the CEC project, e.g., DOE-2 models drapes as a SHADING-FRACTION, EnergyPlus models them as internal shading surface requiring 10 inputs; DOE-2 allows a distribution loss in the water loop, EnergyPlus didn't; DOE-2 degrades the wind speed in its infiltration calculation, EnergyPlus didn't; DOE-2 allows a thermostat throttling range; EnergyPlus didn't; etc., etc. (some of these limitations in EnergyPlus may have been corrected since 2007). <o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><B style="mso-bidi-font-weight: normal"><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><FONT face=Calibri>Since I had access to both the DOE-2 and EnergyPlus source code at the time, I believe I did the most thorough job possible in matching inputs</FONT></SPAN></B><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><FONT face=Calibri>, but even so I had to "punt" in numerous places (no drapes, infiltration at raw wind speed, etc.) for the sake of an "apples-to-apples" comparison. <B style="mso-bidi-font-weight: normal">Yet, even under these ground rules, I was still seeing up to 40% differences in heating loads in some cases.</B><BR><BR>4) So which are the correct, or better, results? I really can't say. When you look into the codes, there is room for questioning the solution techniques in both programs<B style="mso-bidi-font-weight: normal">
. Just by dint of having seen many more DOE-2 results, I tended to regard them as the "conventional wisdom",</B> but then conventional wisdom could always be wrong. Maybe we have been overestimating the heating energies in California all these years. After reading through this litany of problems, some may want to throw up their hands and say either, "it's hopeless" or even, "who cares?". That to me is a wrong and dangerous response, because it ultimately damages the credibility of simulations. <B style="mso-bidi-font-weight: normal">Going back to China, many experts there have become disenchanted and distrustful of simulations, and are calling for it NOT to be used for compliance calculations.</B> <o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><FONT face=Calibri>The same can happen here, as well. So, I think we need to spend more effort to have a better sense of the relative performance of different programs, and what is the "ground truth". Doing a parallel set of calibrated simulations against good monitored data would be a good start. <BR><BR>Joe<BR><BR>Joe Huang<BR>White Box Technologies, Inc.<BR>346 Rheem Blvd., Suite 108D<BR>Moraga CA 94556<BR>yjhuang@whiteboxtechnologies.com<BR>www.whiteboxtechnologies.com<BR>(o) (925)388-0265<BR>(c) (510)928-2683<BR>"building energy simulations at your fingertips"<BR><BR>-------------------------------------------------------<BR>On Wed, Apr 27, 2011 at 6:06 PM, Joe Huang <BR><yjhuang@whiteboxtechnologies.com <BR><</FONT><A href="javascript:main.compose('new',%20't=yjhuang@whiteboxtechnologies.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>
mailto:yjhuang@whiteboxtechnologies.com</FONT></SPAN></A><FONT face=Calibri>>wrote:<BR>><BR>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.<BR>><BR>Joe<BR>><BR>Joe Huang<BR>White Box Technologies, Inc.<BR>346 Rheem Blvd., Suite 108D<BR>Moraga CA 94556<BR>
yjhuang@whiteboxtechnologies.com <</FONT><A href="javascript:main.compose('new',%20't=yjhuang@whiteboxtechnologies.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:yjhuang@whiteboxtechnologies.com</FONT></SPAN></A><FONT face=Calibri>><BR>www.whiteboxtechnologies.com <</FONT><A href="http://www.whiteboxtechnologies.com/" target=l><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>http://www.whiteboxtechnologies.com/</FONT></SPAN></A><FONT face=Calibri>><BR>(o) (925)388-0265<BR>(c) (510)928-2683<BR>"building energy simulations at your fingertips"<BR>=============================================<o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><FONT face=Calibri>Paul Diglio wrote:<BR>Mizra:<BR>Thank you for the time it took you to send the results of your study <BR>to the forum. Some of the top simulation firms in my area use Energy <BR>Plus and I was confused when other people claimed a higher discrepancy <BR>rate than you modeled.<BR><BR>Paul Diglio<BR><BR>*From:* Mirza Sajjal <Mirza.Sajjal@BuroHappold.com><BR>*To:* Pasha Korber-Gonzalez <pasha.pkconsulting@gmail.com>; deepika <BR>khowal <deepika.khowal@gmail.com><BR>*Cc:* equest-users@lists.onebuilding.org; energyplus_support <BR><EnergyPlus_Support@yahoogroups.com><BR>*Sent:* Thu, April 28, 2011 5:55:09 PM<BR>*Subject:* Re: [Equest-users] equest and energy plus outputs<BR>><BR>This was a little study I did out of curiosity last year, and the <BR>results between eQUEST (v3.63) and EnergyPlus (v4.0) matched quite <BR>
well (~1.4% difference). All the schedules, zone areas, surface areas <BR>were exactly the same (I checked), but I also chose a simple system; <BR>PTAC units for the comparison. I believe when I was doing this I had <BR>checked the performance curves that were being used in EnergyPlus and <BR>they matched the eQUEST curves.<BR>><BR>I assume the results will begin to differ when the systems become more <BR>complicated, but even then I believe if both models are calibrated to <BR>match as much as possible the results shouldn�t vary significantly <BR>(assuming all systems are native to the programs and we�re not <BR>creating work-arounds i.e. DOAS in eQUEST using dummy zones or the like).<BR>><BR><SPAN style="mso-spacerun: yes"> </SPAN>(FYI, the geometry was ported over to EnergyPlus through a tool I <BR>wrote using Excel and VBA, but it�s a messy process)<BR>><BR>Following are some of the results and graphical outputs:<BR>><BR>*Mirza Sajjal*<BR>Engineer<BR>
Buro Happold<BR>100 Broadway<BR>New York, NY 10005<BR>Tel: +1 212 334 2025<BR>Direct: +1 212 616 0380<BR>><BR><SPAN style="mso-spacerun: yes"> </SPAN><BR><BR>*From:* equest-users-bounces@lists.onebuilding.org <BR>[</FONT><A href="javascript:main.compose('new',%20't=equest-users-bounces@lists.onebuilding.org]')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:equest-users-bounces@lists.onebuilding.org]</FONT></SPAN></A><FONT face=Calibri> *On Behalf Of <BR>*Pasha Korber-Gonzalez<BR>*Sent:* Thursday, April 28, 2011 4:46 PM<BR>*To:* deepika khowal<BR>*Cc:* equest-users@lists.onebuilding.org; energyplus_support<BR>*Subject:* Re: [Equest-users] equest and energy plus outputs<BR>><BR>As I understand it--Energy+ is free-ware in it's raw form. I guess <BR>I was wrong to make an assumption that Deepika is using it without an <BR>interface. If this is not the case it might explain such a variance <BR>
in results. When I model in DOE-2 raw form---it is so much harder <BR>for me to manage my data and inputs in my head and such----I was not <BR>born to be a programmer, and it gives me nightmares from struggling to <BR>pass FORTRAN so many years ago...ugh.<BR>><BR>Therefore, I haven't looked at E+ myself for a very long time and <BR>purchasing or putting out the cost for the user-interface programs is <BR>not as desireable as using the eQuest free-ware. or the future <BR>CANQuest free-ware (future SI version).<BR>><BR>BUT-- I know that E+ is supposed to have some great capabilities in <BR>which we are limited with DOE-2 (to an extent.) Has anyone else had <BR>the time and desire to compare these program engines more closely <BR>recently? Also--why is it so difficult to "match" systems in eQuest <BR>and E+....forgive my blase'-ness, but isn't a pkgd system a pkgd <BR>system...a pkgd system??? :)<BR>><BR>
Pasha<BR><SPAN style="mso-spacerun: yes"> </SPAN><BR>><BR>On Thu, Apr 28, 2011 at 11:39 AM, deepika khowal <BR><deepika.khowal@gmail.com <</FONT><A href="javascript:main.compose('new',%20't=deepika.khowal@gmail.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:deepika.khowal@gmail.com</FONT></SPAN></A><FONT face=Calibri>>wrote:<BR>><BR>So based on my analysis, there is a difference of about 10% in results <BR>of equest and E+. I would believe that because there are certain <BR>parameters which are very difficult to match.<BR>><BR>this seems reasonable to me.<BR>><BR>On Thu, Apr 28, 2011 at 9:09 AM, John Aulbach <jra_sac@yahoo.com <BR><</FONT><A href="javascript:main.compose('new',%20't=jra_sac@yahoo.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:jra_sac@yahoo.com</FONT></SPAN></A><FONT face=Calibri>>wrote:<BR>><BR>
I am sure EnergyPlus is a fine and well thought out program (consider <BR>the sources and fine people involved). However, since I am in <BR>production mode (and don't have time to create a model in two <BR>different programs-who pays for THAT), I chose to migrate to eQuest <BR>after DOE-2.1 A, B, C, D, and E. There are plenty of resources to ask <BR>questions of, the program started out in Windows (didn't need "add <BR>ons"), and gives me a 3-D rendering on the building immediately.<BR>><BR>I dealt with 20 years of "raw" DOE-2, where I didn't know what my <BR>building really looked like (until Joe Huang came along with BDL <BR>Draw..). So I would need at age (you guess..) to not relearn an <BR>entirely new program and stick with what I had learned over the past <BR>25+ years.<BR>><BR>John R. Aulbach, PE, CEM<BR>Senior Energy Engineer<BR>*Partner** **Energy*<BR>1990 E. Grand Avenue, El Segundo, CA 90245<BR>
W: 888-826-1216, X254| D: 310-765-7295 | F: 310-817-2745<BR>www.ptrenergy.com <</FONT><A href="http://www.ptrenergy.com/" target=l><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>http://www.ptrenergy.com/</FONT></SPAN></A><FONT face=Calibri>| jaulbach@ptrenergy.com <BR><</FONT><A href="javascript:main.compose('new',%20't=%7C%20jaulbach@ptrenergy.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:%7C%20jaulbach@ptrenergy.com</FONT></SPAN></A><FONT face=Calibri>><BR><SPAN style="mso-spacerun: yes"> </SPAN><BR>><BR>*From:* deepika khowal <deepika.khowal@gmail.com <BR><</FONT><A href="javascript:main.compose('new',%20't=deepika.khowal@gmail.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:deepika.khowal@gmail.com</FONT></SPAN></A><FONT face=Calibri>>><BR>*To:* Paul Diglio <paul.diglio@sbcglobal.net <BR><</FONT>
<A href="javascript:main.compose('new',%20't=paul.diglio@sbcglobal.net')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:paul.diglio@sbcglobal.net</FONT></SPAN></A><FONT face=Calibri>>><BR>*Cc:* equest-users@lists.onebuilding.org <BR><</FONT><A href="javascript:main.compose('new',%20't=equest-users@lists.onebuilding.org')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:equest-users@lists.onebuilding.org</FONT></SPAN></A><FONT face=Calibri>>; energyplus_support <BR><EnergyPlus_Support@yahoogroups.com <BR><</FONT><A href="javascript:main.compose('new',%20't=EnergyPlus_Support@yahoogroups.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:EnergyPlus_Support@yahoogroups.com</FONT></SPAN></A><FONT face=Calibri>>><BR>*Sent:* Thu, April 28, 2011 8:56:34 AM<BR>><BR>*Subject:* Re: [Equest-users] equest and energy plus outputs<BR>><BR>
As Joe and others mentioned, its really difficult to create all <BR>parameters same in both softwares.<BR>><BR>I am still working on it .<BR>><BR>For ex, which system should I use in equest as equivalent to unitary <BR>system in E+?<BR>><BR>I understand its difficult to match every input and hence, getting <BR>same results is very tricky.<BR>><BR>Thanks all for their inputs<BR>><BR><SPAN style="mso-spacerun: yes"> </SPAN><BR>><BR>On Thu, Apr 28, 2011 at 4:54 AM, Paul Diglio <BR><paul.diglio@sbcglobal.net <</FONT><A href="javascript:main.compose('new',%20't=paul.diglio@sbcglobal.net')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:paul.diglio@sbcglobal.net</FONT></SPAN></A><FONT face=Calibri>>wrote:<BR>><BR>I thought E+ is a free program? I would be interested to hear from <BR>anyone who has used Google SketchUp and the Open Studio Plug-in to <BR>generate a 3D view in E+.<BR>><BR>
I would like to hear more about the discrepancies between eQuest and <BR>E+ from those who use both programs.<BR>><BR>Paul Diglio<BR>><BR style="mso-special-character: line-break"><BR style="mso-special-character: line-break"><o:p></o:p></FONT></SPAN></P>
<P style="MARGIN: 0in 0in 10pt" class=MsoNormal><SPAN style="LINE-HEIGHT: 115%; FONT-SIZE: 12pt"><FONT face=Calibri>*From:* Pasha Korber-Gonzalez <pasha.pkconsulting@gmail.com <BR><</FONT><A href="javascript:main.compose('new',%20't=pasha.pkconsulting@gmail.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:pasha.pkconsulting@gmail.com</FONT></SPAN></A><FONT face=Calibri>>><BR>*To:* deepika khowal <deepika.khowal@gmail.com <BR><</FONT><A href="javascript:main.compose('new',%20't=deepika.khowal@gmail.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:deepika.khowal@gmail.com</FONT></SPAN></A><FONT face=Calibri>>><BR>*Cc:* energyplus_support <EnergyPlus_Support@yahoogroups.com <BR><</FONT><A href="javascript:main.compose('new',%20't=EnergyPlus_Support@yahoogroups.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>
mailto:EnergyPlus_Support@yahoogroups.com</FONT></SPAN></A><FONT face=Calibri>>>; <BR>equest-users@lists.onebuilding.org <BR><</FONT><A href="javascript:main.compose('new',%20't=equest-users@lists.onebuilding.org')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:equest-users@lists.onebuilding.org</FONT></SPAN></A><FONT face=Calibri>><BR>*Sent:* Thu, April 28, 2011 1:27:44 AM<BR>*Subject:* Re: [Equest-users] equest and energy plus outputs<BR>><BR><BR>Hmmm- an energy plus model showed 50% less energy use (EUI) than <BR>eQuest? Did you use the same weather files? (i.e. convert the EPW <BR>you used in E+ to .bin and use the same weather file in eQuest?)<BR>><BR>If this is truly the case, this is unsettling as a simulator. <BR>Wouldn't it be safer for our clients to error on the conservative side <BR>and give the eQuest results instead of the E+ results?<BR>><BR>
Also--if this is the case, then what is the market advantage to <BR>spending thousands of dollars on E+ software rather than use the <BR>FREE-ware eQuest program??<BR>><BR>I'd appreciate any commentary to help me "see the light" of this <BR>topic. And if Deepika is willing to share a visual of his energy <BR>results output, I'm super curious to see what it is showing...<BR>><BR>Good question/good info...thanks,<BR>Pasha<BR>Korber Energy Consultants<BR><BR><SPAN style="mso-spacerun: yes"> </SPAN><BR>><BR>On Wed, Apr 27, 2011 at 7:11 PM, deepika khowal <BR><deepika.khowal@gmail.com <</FONT><A href="javascript:main.compose('new',%20't=deepika.khowal@gmail.com')"><SPAN style="FONT-FAMILY: 'Verdana','sans-serif'"><FONT color=#0000ff>mailto:deepika.khowal@gmail.com</FONT></SPAN></A><FONT face=Calibri>>wrote:<BR>><BR>Thanks Joe<BR>><BR>Even I realized the same thing. the total energy use in Energy plus <BR>was almost 50% less than equest.<BR>
><BR>If this is the case, who would you know that you model is working fine?<BR><BR>><BR><BR>><BR>deepika khowal wrote:<BR>HI All<BR>I am trying to create same model in equest and energy plus to see <BR>whether i see same results and just to validate my simulation files.<BR>has anyone done this before?<BR>I would like to know what is the % difference in both software outputs?<BR>Thanks<BR>Deepika<BR>><BR>_______________________________________________ </FONT></SPAN><SPAN style="LINE-HEIGHT: 115%; FONT-FAMILY: 'Arial','sans-serif'; FONT-SIZE: 12pt; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi"><o:p></o:p></SPAN></P>
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