<div>I quickly go through 90.1 UM and notice: </div><div> </div><div>1. As per Appendix G, UM highlights that "these values may be used only if actual schedule are not know"; </div><div>2. As per schedule for occupancy -hotel/motel, the percent varies from 90% (night) to 20% (noon). It is quite reasonable to me provided no actual schedule are known. I guess you can further reduce it proportionally if you are able to get more info, such as optimal occupancy rate for the hotel. </div>
<div>3. There is no schedule for fan running 100% but HVAC system. You can understand it as running 100% on time for HVAC system with occupancy sensors since you have PTHP providing both conditioning and OA in individual rooms. Fan power will be calculated with respect to occupancy schedule in this manner. </div>
<div>4. Bear in mind, your baseline will be PTAC or PTHP for hotel. You will probably overestimate fan energy savings if you are to use the by-default schedule (and you believe the real occupancy rate will be differnt). </div>
<div>5. To me, such schedule is more important and sensitive for M&V modeling. I will not bother about using by-default occupancy schedule for LEED/incentive modeling. </div><div> </div><div><font face="comic sans ms,sans-serif">Regards, </font></div>
<div><font face="comic sans ms,sans-serif"></font> </div>
<div><font face="comic sans ms,sans-serif">Cheney</font></div>
<div><font face="comic sans ms,sans-serif"></font> </div>
<div><font face="comic sans ms,sans-serif">LinkedIN @ </font><a href="http://ca.linkedin.com/pub/yu-cheney-chen/27/637/72b" target="_blank"><font face="comic sans ms,sans-serif">http://ca.linkedin.com/pub/yu-cheney-chen/27/637/72b</font></a><font face="comic sans ms,sans-serif"> </font></div>
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<br><br><div class="gmail_quote">On Fri, Oct 21, 2011 at 8:51 AM, Jim Dirkes <span dir="ltr"><<a href="mailto:jim@buildingperformanceteam.com">jim@buildingperformanceteam.com</a>></span> wrote:<br><blockquote style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;" class="gmail_quote">
<div lang="EN-US" vlink="purple" link="blue"><div><p class="MsoNormal"><span style="font-family: "Georgia","serif"; font-size: 10pt;">Dear Forum,<br>Assuming:<u></u><u></u></span></p><p style="margin-left: 38.25pt;" class="MsoNormal">
<u></u><span style="font-family: Symbol; font-size: 10pt;"><span>·<span style="font: 7pt/normal "Times New Roman"; font-size-adjust: none; font-stretch: normal;"> </span></span></span><u></u><span style="font-family: "Georgia","serif"; font-size: 10pt;">10 story hotel with 200 guest rooms facing all compass directions <u></u><u></u></span></p>
<p style="margin-left: 38.25pt;" class="MsoNormal"><u></u><span style="font-family: Symbol; font-size: 10pt;"><span>·<span style="font: 7pt/normal "Times New Roman"; font-size-adjust: none; font-stretch: normal;"> </span></span></span><u></u><span style="font-family: "Georgia","serif"; font-size: 10pt;">Each guest room has HVAC and outdoor air from a through-the-wall heat pump<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family: "Georgia","serif"; font-size: 10pt;">How can I create a simple modeling scheme and schedules which will reflect normal occupancy variations?<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family: "Georgia","serif"; font-size: 10pt;">As I think about it, the reality of operation is quite different than a central HVAC unit, because random individual rooms can be completely off, while others are on. Room temperature, ventilation and fan power are all affected. There will be no predictable pattern for which rooms are unused or unoccupied. ASHRAE does have some typical use patterns in their 90.1 User Manual but, for example, they assume 100% on time for fans. That's too coarse for my taste, and will overestimate energy substantially.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family: "Georgia","serif"; font-size: 10pt;">I REALLY don't want to model 200 individual zones with varying schedules! I know that I'm not the first one to wrestle with this idea, so I am hoping for some creative insight from you.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family: "Georgia","serif"; font-size: 10pt;">Thanks in advance!<u></u><u></u></span></p><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal"><img alt="Description: BPT BizCard JVDII Updated" src="cid:image003.jpg@01CC8FE7.C58707C0" width="336" height="192"><u></u><u></u></p><p class="MsoNormal"><b><span style="font-size: 10pt;"><u></u> <u></u></span></b></p>
<p class="MsoNormal"><span style="font-size: 10pt;">Tolerance is not agreement. Tolerance is precisely the willingness to restrain from the use of coercion. (and who hasn’t experienced the benefit of respectful, constructive <u>dis</u>agreement?)</span><b><span style="font-size: 10pt;"><u></u><u></u></span></b></p>
<p class="MsoNormal"><u></u> <u></u></p></div></div><br>_______________________________________________<br>
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