<div dir="ltr">
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span style="color:black" lang="EN-CA">Two questions
on how ASHRAE 90.1 2010 considers district (“purchased”) steam, for both ECB
and Appendix G, for NON-LEED projects (e.g. code compliance using ECB) … so one
can’t rely on supplementary LEED guidance on DES (i.e. “</span><span lang="EN-CA">Treatment of District or Campus
Thermal Energy in LEED V2 and LEED 2009 – Design & Construction”).<span style="color:black"></span></span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span style="color:black" lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span style="color:black" lang="EN-CA">“[…] Appendix
G’s direction for projects using purchased […] heating is intended to remove
the impact of […] heating <u>source equipment</u> efficiencies from the building
performance rating by using the same purchased energy rates in the baseline and
proposed designs.”</span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin:0cm 0cm 0.0001pt 35.4pt;line-height:normal"><i><span style="color:black" lang="EN-CA">taken from:</span></i></p>
<p class="MsoNormal" style="margin:0cm 0cm 0.0001pt 35.4pt;line-height:normal"><i><span style="color:black" lang="EN-CA">INTERPRETATION IC 90.1-2010-31
OF ANSI/ASHRAE/IES STANDARD 90.1-2010<br>
Energy Standard for Buildings Except Low-Rise Residential Buildings<br>
Date Approved: January 28, 2017</span></i></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">So
ECB & Appendix G 2010 do not recognize 'source' (e.g. central plant) equipment
efficiencies (fair enough, not a building asset). Energy savings can stem
though from baseline HVAC system selection, control parameters, and secondary
equipment efficiencies such as building-side hot water pumps. Up to now,
everything's clear.</span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">Question
1: Shall the primary steam-to-water heat exchanger - the interface between a publicly-
or privately-owned/operated district heating (steam) system and the building
(hot water distribution) – be considered part of the <u>source</u> (therefore ‘neutral’,
i.e. no credits or penalties should be accounted for) or part of the <u>building</u>
asset (hence a potential source of recognized energy savings depending on e.g. exchanger
selection)? In most cases, the heat exchanger is actually a building asset, owned
and operated by the building owner. And as there are industry claims of heat
exchange improvements of around 10% depending on exchanger selection and ‘steam
conditioning’ technology, it’s understandably a fair question for cold climate
locations.</span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">Question
2: If the answer to Question 1 is that the primary steam-to-water exchanger,
and associated technologies, may be considered part of the 'building' (and therefore
a potential source of recognized energy savings), then it raises the question
what would be the baseline heat exchange coefficient or efficiency? Without the
latter, it’s hard to take into consideration steam-to-water conversion
improvements.</span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">Past
forum discussions have mainly dealt with LEED buildings (which has its own
non-90.1 way of doing things), or on modeling solutions (e.g. setting up a STEAM-METER
in DOE-2.2). But I can’t find clear guidance to answering Questions 1 & 2.</span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA"> </span></p>
<p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">Thanks.</span></p><p class="MsoNormal" style="margin-bottom:0.0001pt;line-height:normal"><span lang="EN-CA">-</span></p><div style="font-family:tahoma,sans-serif;display:inline" class="gmail_default"> Denis</div><br><p></p>
<div class="gmail_default" style="font-family:tahoma,sans-serif"><br></div><div><div class="gmail-m_2257804581632925681gmail_signature"><div dir="ltr"><font face="'trebuchet ms', sans-serif" size="1">Denis Bourgeois PhD | <a href="mailto:denis@rd2.ca" target="_blank">denis@rd2.ca</a></font></div></div></div>
</div>