<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags"
name="City" downloadurl="http://www.5iamas-microsoft-com:office:smarttags"/>
<o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags"
name="place" downloadurl="http://www.5iantlavalamp.com/"/>
<!--[if !mso]>
<style>
st1\:*{behavior:url(#default#ieooui) }
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
p.MsoAutoSig, li.MsoAutoSig, div.MsoAutoSig
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:Arial;
color:windowtext;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
/* List Definitions */
@list l0
{mso-list-id:122769812;
mso-list-type:hybrid;
mso-list-template-ids:-1507265946 67698689 67698691 67698693 67698689 67698691 67698693 67698689 67698691 67698693;}
@list l0:level1
{mso-level-number-format:bullet;
mso-level-text:\F0B7;
mso-level-tab-stop:.5in;
mso-level-number-position:left;
text-indent:-.25in;
font-family:Symbol;}
ol
{margin-bottom:0in;}
ul
{margin-bottom:0in;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks for all the many great replies to my query on Net
Zero, and use of bio-mass CHP in addition to PV and wind in this context.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>To me, Net Zero is a very powerful term, and there are some important
strict definitions and also a lot of support for interpreting the term on a
project by project basis. Net zero takes us out of achieving some percent
of energy reduction in to the realm of true sustainability. Net Zero has
been applied primarily to homes, but would be a potent tool for commercial and
institutional buildings as well. At the strictest level Net Zero energy refers
to a building that generates annually on-site from on-site available renewable
sources enough energy to equal the annual building energy usage. This
goal is a subset of the goal that buildings meet all of their energy needs from
renewable sources in some way. To me the Net Zero concept provides
several benefits. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<ul style='margin-top:0in' type=disc>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Benchmark for measuring
achievement of a very aggressive energy design <o:p></o:p></span></font></li>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>A target that can shape any
design and orient design towards a truly sustainable energy endpoint<o:p></o:p></span></font></li>
<li class=MsoNormal style='mso-list:l0 level1 lfo1'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>A “sexy” marketing
tool/concept to really help promote a step up from LEED and other energy %
reduction targets (which are great, but not enough)<o:p></o:p></span></font></li>
</ul>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Several people provided the link to
a good summary article from BuildingGreen.com, in the October 2005 edition,
that covers four NREL definitions related to Net Zero </span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><a
href="http://www.buildinggreen.com/articles/">http://www.buildinggreen.com/articles/</a>
</span></font><font size=2 face=Arial><span style='font-size:10.0pt;font-family:
Arial'>(Need to subscribe on line to download article)</span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>
</span></font><font size=2 face=Arial><span style='font-size:10.0pt;font-family:
Arial'>The first of these is the strictest version noted above. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Zero-net annual site-energy<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Zero-net annual source energy<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Zero-net annual energy cost<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Zero-net annual emissions<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Another resource is a NAHB study on a net zero home model,
which also provides these definitions, and other useful references, and is
available for free. <a
href="http://www.toolbase.org/tertiaryT.asp?TrackID=&CategoryID=1979&DocumentID=4777">http://www.toolbase.org/tertiaryT.asp?TrackID=&CategoryID=1979&DocumentID=4777</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Another way to consider this is in terms of what type of
renewables are in the project. Perhaps there is a hierarchy:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>0) Conservation/Efficiency<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>1) True off-grid on-site generation from solar and
wind only<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>2) Net zero, utility connected, meeting annual average
energy usage from solar and wind only<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>3) Add other renewables with off-site fuel supply to
2), such as bio-mass, wood and wood pellets, bio-diesel, ideally with combined
heat and power<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>4) Purchased renewables<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Achieving 1 and 2 for commercial buildings above a story or
two in an urban setting is going to be very difficult, because the area
available for PV compared to square footage of the building is so small. (one
person suggested the vertical axis wind turbines may be worth a closer look) Yet
these commercial buildings are critical to push towards a sustainable energy
design building stock. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>There may be value in preserving “Net Zero Energy”to
refer strictly to 1) and 2), with on-site solar and wind only. The
concept is so powerful and useful in marketing and pushing the ideas with the
people who will pay for it and design to it, that I think we need to find a way
to use the terms more broadly. As some pointed out, this is already being
done with Zero Energy Homes, that may actually be 60% from renewables not
100%. I plan to use the term “Nearly Net Zero”, or perhaps “Net
Zero with PV and Off-site Wood”, and define if this is Nearly Net Zero for
a. Energy, b. Source Energy, c. Energy Cost, and/or d. Emissions. It may
be reasonable or possible to assign a number description to this to help make
comparisons. For example, the project I am working on is getting to
Nearly Net Zero Energy using conservation, PV, and a wood pellet CHP unit.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Conservation (below ASHRAE 90.1 or other baseline): 70%<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>PV (or wind) on-site (true net zero generation): 15%<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Other renewables generated on-site (possible off-site fuel):
15%<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Purchased Renewables: 0%
(not needed to offset usage for my project, but
also will be buying green power) <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>-----------------------------------------<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Nearly Net Zero: 70/15/15/0<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Here are some possible ways to carry the ideas forward. Many
commentators on this string, and the Building Green article promote using the
concept of Net Zero to push us into another level of energy achievement.
I would appreciate any additional comments on this. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Brian Thornton, PE<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoAutoSig><st1:City w:st="on"><st1:place w:st="on"><font size=2
face=Arial><span style='font-size:11.0pt;font-family:Arial'>Thornton</span></font></st1:place></st1:City><font
size=2 face=Arial><span style='font-size:11.0pt;font-family:Arial'> Energy
Consulting<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>p. 503-231-6600 f. 503-231-3555<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face=Arial><span style='font-size:11.0pt;
font-family:Arial'>thorntonenergy@comcast.net<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<PRE>
===========================
You received this e-mail because you are subscribed
to the BLDG-SIM@GARD.COM mailing list. To unsubscribe
from this mailing list send a blank message to
BLDG-SIM-UNSUBSCRIBE@GARD.COM
</PRE></body>
</html>