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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText>You’ll have to calculate the heating portion of your hybrid loop separately since DOE2 doesn’t allow this setup. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>The easiest way I can think of would be to export the hourly GHEX report, find the instances where the ground loop temperature dips below your design setpoint, take the corresponding heating load served by the GHEX for that hour and then replace that GHEX energy with boiler energy. Don’t forget to properly account for pumping energy depending on how the loops will operate as designed. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Notice I said <i>easiest</i>, not the most accurate. It’s important to know how this method will skew your results. In this case, you’ll artificially be cooling your ground loop in the winter months (when the boiler is operating) and pulling that energy back out in the summer cooling months for free. This could have a significant impact on the annual average efficiency (artificially inflating) of the heat pumps. <o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoNormal><b><span style='color:#0F243E'>Anthony Hardman, PE<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:9.0pt;color:#0F243E'>LEED AP BD&C</span></b><b><span style='color:#0F243E'><o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;color:#0F243E'>Building Performance Analyst<o:p></o:p></span></p><p class=MsoNormal><b><u><span style='color:#00B050'><a href="http://www.greenengineer.com/"><span style='color:#00B050'>THE GREEN ENGINEER, LLP</span></a></span></u></b><b><u><span style='color:#00B050'><o:p></o:p></span></u></b></p><p class=MsoNormal><b><span style='color:#00B050'>Sustainable Design Consulting – Energy Modeling – LEED Project Management </span></b><o:p></o:p></p><p class=MsoNormal><span style='font-size:10.0pt;color:#0F243E'>50 Beharrell St<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;color:#0F243E'>Concord, MA 01742<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;color:#0F243E'>O: 978/610-2801<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;color:#0F243E'>C: 720/840-7862<o:p></o:p></span></p><p class=MsoPlainText>-----Original Message-----<br>From: equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org] On Behalf Of Dane Heimerman<br>Sent: Monday, December 13, 2010 12:24 PM<br>To: equest-users@lists.onebuilding.org<br>Subject: [Equest-users] Ground source heat pump/ cooling tower hybrid<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Hi there,<o:p></o:p></p><p class=MsoPlainText>We have a building that is conditioned with water source heat pumps. The loop is maintained by several ground source wells, and also a closed loop evaporative cooling tower and a hot water boiler. Does anyone know how to correctly model this loop? Equest will let you put a boiler and a cooling tower on a ground loop with the wells, but when you run the simulation it gives an error that says a boiler cannot be on the loop with the ground source heat exchanger.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Any advice is appreciated.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Thanks in advance,<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>--<o:p></o:p></p><p class=MsoPlainText>Dane Heimerman<o:p></o:p></p><p class=MsoPlainText>HVAC Engineer<o:p></o:p></p><p class=MsoPlainText>Michael L. Norris& Associates, Inc.<o:p></o:p></p><p class=MsoPlainText>270 Walker Dr, Suite 201B<o:p></o:p></p><p class=MsoPlainText>State College, PA 16801<o:p></o:p></p><p class=MsoPlainText>p:814.867.3823<o:p></o:p></p><p class=MsoPlainText>f:814.867.4823<o:p></o:p></p><p class=MsoPlainText><a href="mailto:daneh@mlnai.com"><span style='color:windowtext;text-decoration:none'>daneh@mlnai.com</span></a><o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>_______________________________________________<o:p></o:p></p><p class=MsoPlainText>Equest-users mailing list<o:p></o:p></p><p class=MsoPlainText><a href="http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org"><span style='color:windowtext;text-decoration:none'>http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org</span></a><o:p></o:p></p><p class=MsoPlainText>To unsubscribe from this mailing list send a blank message to <a href="mailto:EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG"><span style='color:windowtext;text-decoration:none'>EQUEST-USERS-UNSUBSCRIBE@ONEBUILDING.ORG</span></a><o:p></o:p></p></div></body></html>