Hi all,<div><br></div><div>Thank you guys for bringing this up. </div><div><br></div><div>I'd like to ask a simple question about the occupancy assumption. Do we need to match the occupancy density to the assumed occupancy (usually peak or dense) by the HVAC designer, in the model? Often times HVAC designers assume more occupants for peak load.</div>
<div><br></div><div>I understand that simulation needs to be close to reality as possible but if I will reduce the occupancy close to reality, savings may be reduced due to increase in the HVAC equipment capacity difference between the baseline & proposed because the baselines equipment will be auto-sized (1.15 ratio for cooling, 1.25 for heating).</div>
<div><br></div><div>Have you experienced a comment from a reviewer picking on inconsistencies on assumed occupancy between other credit/prerequisites?</div><div><br></div><div>Thanks,</div><div>Bob</div><div><br></div><div>
<br><div class="gmail_quote">2011/9/29 Nick Caton <span dir="ltr"><<a href="mailto:ncaton@smithboucher.com">ncaton@smithboucher.com</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div lang="EN-US" link="blue" vlink="purple"><div><p class="MsoNormal"><span style="color:#1F497D">Hi Joey,<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal">
<span style="color:#1F497D">I thought to write about the 25% topic but thought it best to not bring it up… Perhaps a quick recap is in order for your situation and others’ benefit!<u></u><u></u></span></p><p class="MsoNormal">
<span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">There has been much discussion regarding that “25% rule” between myself and others on these lists ([bldg-rate], [bldg-sim], [equest-users]). Re: archives.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">I started out with the same conclusion you’re stating: the baseline consumption is supposed to be 25% plug/process loads. The LEED 2.2 handbook is unfortunately worded under EAc1 to suggest this as a prescriptive default in the absence of substantial documentation, but that “documentation” can be as simple as a one-line reference as I described. Note the LEED v3 handbook (under EAp2 I think) re-words those lines on process loads to emphasize the expectation is to simply match between the models – no mention of 25%. <u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">I have since that time done an about face on that viewpoint and believe that figure to be entirely arbitrary. “Forcing” 25% plug load consumption in the baseline is in many cases arbitrarily detrimental to the overall performance rating, is rarely realistic, and the resulting internal gains can cause irresolvable unmet hours for proposed equipment of a specified capacity (remembering the baseline and proposed should normally have matching process loads). I came to the lists seeking to share and learn better approaches to “fairly” mitigate these artificial internal loads, and in doing so learned I was far off the path from others.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">I could re-iterate my perception of the history and intent behind the 25% figure, but you’re probably best advised to seek out those discussions in the archives to come to a fuller understanding. I would presently advise referencing and using something <u>reasonable</u> for your proposed building in both models, and not treating the 25% figure as a mandate, but do inform yourself by reading those archived discussions so that you can defend your position against any argumentative v2.2 reviewer. <u></u><u></u></span></p>
<div class="im"><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">~Nick<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p>
<div><p class="MsoNormal"><span style="color:#1F497D"><img width="119" height="37" src="cid:image001.jpg@01CC7E81.74A03880" alt="cid:489575314@22072009-0ABB"></span><b><span style="color:#2D4D5E"><u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="color:#2D4D5E"><u></u> <u></u></span></b></p><p class="MsoNormal"><b><span style="font-size:12.0pt;color:#2D4D5E">NICK CATON, P.E.</span></b><b><span style="font-size:12.0pt;color:#2D4D5E"><u></u><u></u></span></b></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900">SENIOR ENGINEER<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">Smith & Boucher Engineers</span><span style="font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">25501 west valley parkway, suite 200<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">olathe, ks 66061<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">direct <a href="tel:913.344.0036" value="+19133440036" target="_blank">913.344.0036</a><u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">fax <a href="tel:913.345.0617" value="+19133450617" target="_blank">913.345.0617</a><u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><a href="http://www.smithboucher.com" title="blocked::www.smithboucher.com" target="_blank"><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"><u></u><u></u></span></p>
</div><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p></div><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">From:</span></b><span style="font-size:10.0pt"> Jiao, Joey [mailto:<a href="mailto:Joey.Jiao@WSPGroup.com.cn" target="_blank">Joey.Jiao@WSPGroup.com.cn</a>] <br>
<b>Sent:</b> Wednesday, September 28, 2011 9:56 PM<br><b>To:</b> Nick Caton<br><b>Subject:</b> </span><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">答复</span><span style="font-size:10.0pt">: [Equest-users] Values choosing of the typical equipment &miscellaneous power densities.<u></u><u></u></span></p>
</div></div><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal"><span style="color:#1F497D">Hi, Nick:<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">Thank you for your suggestion , it’s really helpful!<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I have found the TABLE GB, in ASHRAE 90.1-2007 Manual. See it below. I think it’s what’s your refer to.<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">As an addition, I get another tip which should be a limitation for making a baseline model. <u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D">On the LEED RATING SYSTEM , there is a rule that the process energy cost should be 25% of the total baseline energy cost. <u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">Hope it helpful for others.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Thanks for your help again.<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">Joey<u></u><u></u></span></p>
<p class="MsoNormal"><img border="0" width="778" height="343" src="cid:image002.jpg@01CC7E81.74A03880"><span style="color:#1F497D"><u></u><u></u></span></p><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">发件人</span></b><b><span style="font-size:10.0pt;font-family:SimSun">:</span></b><span style="font-size:10.0pt;font-family:SimSun"> Nick Caton [mailto:<a href="mailto:ncaton@smithboucher.com" target="_blank">ncaton@smithboucher.com</a>] <br>
</span><b><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">发送时间</span></b><b><span style="font-size:10.0pt;font-family:SimSun">:</span></b><span style="font-size:10.0pt;font-family:SimSun"> 2011</span><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">年</span><span style="font-size:10.0pt;font-family:SimSun">9</span><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">月</span><span style="font-size:10.0pt;font-family:SimSun">28</span><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">日</span><span style="font-size:10.0pt;font-family:SimSun"> 22:48<br>
</span><b><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">收件人</span></b><b><span style="font-size:10.0pt;font-family:SimSun">:</span></b><span style="font-size:10.0pt;font-family:SimSun"> Jiao, Joey; <a href="mailto:Equest-users@lists.onebuilding.org" target="_blank">Equest-users@lists.onebuilding.org</a><br>
</span><b><span lang="ZH-CN" style="font-size:10.0pt;font-family:SimSun">主题</span></b><b><span style="font-size:10.0pt;font-family:SimSun">:</span></b><span style="font-size:10.0pt;font-family:SimSun"> RE: [Equest-users] Values choosing of the typical equipment &miscellaneous power densities.<u></u><u></u></span></p>
</div></div><div><div></div><div class="h5"><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal"><span style="color:#1F497D">Generally, the “correct” baseline model values for these entries (misc/plug loads and occupancy/ventilation) are to match whatever is in the proposed model.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">There is more than one “correct” approach regarding misc load quantities for the proposed model. In any case you should be prepared to reproduce what decision you made and back it up for baseline/proposed documentation:<u></u><u></u></span></p>
<p><u></u><span style="color:#1F497D"><span>-<span style="font:7.0pt "Times New Roman""> </span></span></span><u></u><span style="color:#1F497D">Reference tables in the 90.1 users manual (also found in certain state energy codes) with representative W/SF figures for various ‘whole building’ types and assign that figure to each space. I’ve found this approach to be time-efficient and so far totally accepted by the USGBC/LEED reviewers.<u></u><u></u></span></p>
<p><u></u><span style="color:#1F497D"><span>-<span style="font:7.0pt "Times New Roman""> </span></span></span><u></u><span style="color:#1F497D">Stick with the eQuest defaults per occupancy. I’m unsure of where they’re all derived from exactly (Title 24? Some other standard/reference?), but they will vary as you change space activity types and appear sensible from what I’ve observed. These values, default or otherwise, are rolled into a weighted average for each zone group based on the % distribution in the zone group screen – which is why the resulting W/SF coming out of the wizards can appear somewhat random at first glance.<u></u><u></u></span></p>
<p><u></u><span style="color:#1F497D"><span>-<span style="font:7.0pt "Times New Roman""> </span></span></span><u></u><span style="color:#1F497D">Flex your spreadsheet muscles and do a space-by-space plug load takeoff to come up with an “actual” number. I have never pursued this degree of detail myself, but I understand others have specifically to account for gains from providing efficient plug load equipment with the project over “standard” equipment… resulting in a deliberate divergence between the baseline/proposed models. <u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">I’ve found eQuest default values for occupant density/ventilation/loads are pretty much on the mark as to what I’d define from ASHRAE references, so I leave the defaults alone in wizards and only focus on tweaking the calculated zone occupant quantities in detailed mode as necessary for model QC and matching loads. I do make a point to assign the appropriate “space type percentages” for each zone in the following wizard screens however.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1F497D">~Nick<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></span></p>
<div><p class="MsoNormal"><span style="color:#1F497D"><img border="0" width="119" height="37" src="cid:image001.jpg@01CC7E81.74A03880" alt="cid:489575314@22072009-0ABB"></span><b><span style="color:#2D4D5E"><u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="color:#2D4D5E"><u></u> <u></u></span></b></p><p class="MsoNormal"><b><span style="font-size:12.0pt;color:#2D4D5E">NICK CATON, P.E.<u></u><u></u></span></b></p><p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900">SENIOR ENGINEER<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:7.5pt;color:#CC9900"><u></u> <u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">Smith & Boucher Engineers</span><span style="font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">25501 west valley parkway, suite 200<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">olathe, ks 66061<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">direct <a href="tel:913.344.0036" value="+19133440036" target="_blank">913.344.0036</a><u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:10.0pt;color:#2D4D5E">fax <a href="tel:913.345.0617" value="+19133450617" target="_blank">913.345.0617</a><u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><a href="http://www.smithboucher.com" title="blocked::www.smithboucher.com" target="_blank"><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"><u></u><u></u></span></p>
</div><p class="MsoNormal"><span style="color:#1F497D"><u></u> <u></u></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">From:</span></b><span style="font-size:10.0pt"> <a href="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank">equest-users-bounces@lists.onebuilding.org</a> [mailto:<a href="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank">equest-users-bounces@lists.onebuilding.org</a>] <b>On Behalf Of </b>Jiao, Joey<br>
<b>Sent:</b> Wednesday, September 28, 2011 4:59 AM<br><b>To:</b> <a href="mailto:Equest-users@lists.onebuilding.org" target="_blank">Equest-users@lists.onebuilding.org</a><br><b>Subject:</b> [Equest-users] Values choosing of the typical equipment &miscellaneous power densities.<u></u><u></u></span></p>
</div></div><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">Hi, Everyone:<u></u><u></u></p><p class="MsoNormal">I’m confused with the value choosing for the equipment & miscellaneous power densities like the illustrate below.<u></u><u></u></p>
<p class="MsoNormal">The table G 3.1 no.12 said it should be based on the building and space type, but there isn’t other information. So do we need to add this load part when we make a baseline model? <u></u><u></u></p><p class="MsoNormal">
Maybe this isn’t very important , but I want to make sure about it.<u></u><u></u></p><p class="MsoNormal">I know we can choosing the lighting power densities in Section 9, but I can’t find the table for other equipment. So what should you do?<u></u><u></u></p>
<p class="MsoNormal"><img border="0" width="734" height="475" src="cid:image003.png@01CC7E81.74A03880"><u></u><u></u></p><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal"><span style="color:#1F497D">By the way</span> , about the occupancy density and ventilation inputs shown below, I found the reference information from ASHRAE 62.1, is that a common way when we make a baseline? <u></u><u></u></p>
<p class="MsoNormal"><img border="0" width="734" height="475" src="cid:image004.png@01CC7E81.74A03880"><u></u><u></u></p><p class="MsoNormal">Thank you for your kindly help.<u></u><u></u></p><p class="MsoNormal">Best wishes.<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">Joey<u></u><u></u></p><p class="MsoNormal"><b>---------------------------------------------------------------------------<u></u><u></u></b></p><p class="MsoNormal">
<b>Joey Jiao<u></u><u></u></b></p><p class="MsoNormal"><b>Graduate Engineer<span style="color:#1F497D"> </span></b><b><span style="font-size:10.0pt"><u></u><u></u></span></b></p><p class="MsoNormal"><u></u> <u></u></p>
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