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<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=667452716-13022008>Fred,
we are in the process of submitting for CO VFD fan control credit. I feel that
this is still a valid ECM from a LEED perspective for several
reasons:</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=667452716-13022008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=667452716-13022008>1) the
code allows simple fan staging as an alternate compliance path. However, with no
min. # of fans specified one often end sup with just 1 or 2 fans per level.
Staged control in this case will not be equivalent to VFD
control.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=667452716-13022008>2)
local utilities provide incentives for VFDs , which is a strong indicator that
staged is the default and there are energy savings
available.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=667452716-13022008>3)
code allows simple occupancy based controls (on during the day, off at night)
under certain conditions (generally for garages less than 30,000
SF).</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=667452716-13022008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=667452716-13022008>We are
using the code minimum as our definition of standard practice. Fan powers equal
in both cases, just control differences. Have yet to get feedback from USGBC,
but it seems rational to me given other ECMs that have been
credited.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=667452716-13022008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=667452716-13022008>Peter</SPAN></FONT></DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> bldg-sim-bounces@lists.onebuilding.org
[mailto:bldg-sim-bounces@lists.onebuilding.org] <B>On Behalf Of </B>Aleka
Pappas<BR><B>Sent:</B> Wednesday, February 13, 2008 8:22 AM<BR><B>To:</B>
bldg-sim@lists.onebuilding.org<BR><B>Subject:</B> Re: [Bldg-sim] Garage
Ventilation and LEED Credit EA-1<BR></FONT><BR></DIV>
<DIV></DIV>I agree that CO sensor-controlled garage ventilation is standard
practice and the USGBC should not be allowing savings claimed from this control
method. But we've submitted a number of projects for LEED with the
Baseline fans on all the time at 0.75 cfm/SF, and assumed the fans on about 1/4
of this time in the Proposed Building, and the USGBC has allowed it. We've
always stated our assumptions explicitly. There should be a CIR to resolve
this, but so far it's been hard to find motivation on a project to spend the 200
bucks to force them to give the project 1 less LEED point. It's actually a
huge issue for our high-rise condo and office projects....they would be
stretched to say the least to reach the 2 required points without being able to
claim these savings. Which I think would be a good thing. <BR><BR>I've
also worked with a few code jurisdictions around the country who similarly allow
savings from CO vent. control to calculate energy reduction incentives.
<BR><BR>If there's a USGBC person listening in, perhaps they could resolve the
issue with a freebie CIR? <BR><BR>Aleka<BR><BR>
<DIV class=gmail_quote>On Feb 13, 2008 7:37 AM, Fred Porter <<A
href="mailto:FPorter@archenergy.com">FPorter@archenergy.com</A>> wrote:<BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV lang=EN-US
style="MARGIN: 4px 4px 1px; FONT: 10pt Tahoma; font-size-adjust: none; font-stretch: normal"
link="blue" vlink="purple">
<DIV>All,</DIV>
<DIV>While I'm still on my first cup of coffee, and considering the PRM,
general "baseline/budget/reference" model philosophy,
and others' views on safe ventilation, another answer would be the
default "baseline" = "proposed" operation and equipment, where
the PRM does not specifically state a baseline. (You could still take
credit for a premium efficiency fan motor.)</DIV>
<DIV> </DIV>
<DIV>I certainly suspect that savings have been granted to parking garage
"DCV" by lenient reviewers, but it has not surfaced in a CIR. Of course,
clients might think it tacky of us to ask for stricter limitations and
reduced savings and points in a CIR they pay for, which is a problem with
the process. The fact that the baseline is unclear to experienced EA
Cr1/PRM modelers says a lot, since there must be a couple million sf of
ventilated parking garages rated or in the pipeline.</DIV>
<DIV> </DIV>
<DIV>Oh yeah, and what about those heated parking garages under every
"green" office and resort hotel? </DIV>
<DIV> </DIV>
<DIV>And as far as "substituting" the cooling tower fan during summer; I would
think drawing air through the garage with the CT fan would add some
constant load to, or reduce the flow through, that fan, partially
offsetting savings from turning off the garage fan (which would have operated
at a low load factor if controlled by the typical
sensor). </DIV>
<DIV> </DIV>
<DIV>Off to work;</DIV>
<DIV>Fred</DIV>
<DIV><BR><BR>>>> "Fred Porter" <<A
href="mailto:FPorter@archenergy.com"
target=_blank>FPorter@archenergy.com</A>> 2/12/2008 2:27 PM
>>><BR></DIV>
<DIV>
<DIV></DIV>
<DIV class=Wj3C7c>
<DIV>>>> "Michael Tillou" <<A
href="mailto:michael.tillou@gmail.com"
target=_blank>michael.tillou@gmail.com</A>> 2/12/2008 1:31 PM
>>><BR></DIV>
<DIV dir=ltr align=left><FONT face=Arial color=#0000ff size=2><SPAN>Does
anyone know if USGBC is allowing credit for CO Control of parking garage
ventilation? If anyone has any experience with successfully getting
credit for this efficiency measure can you please let me know. I am
curious what is considered a reasonable baseline.</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT face=Arial color=#0000ff
size=2><SPAN></SPAN></FONT><FONT face=Arial color=#0000ff
size=2><SPAN></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><SPAN lang=EN-AU style="FONT-SIZE: 9pt">
<DIV>Dear Colleagues;</DIV>
<DIV>Short answer: I sure hope not!</DIV>
<DIV> </DIV>
<DIV>I very much believe the "reasonable" baseline is CO sensors, so you would
schedule the airflows (thus power, if all goes correctly in model
land) proportional to some assumed activity schedule. (There is a
good summary of what those flows might be in an ASHRAE Jrnl that's about
ten years old but on the AJ website.) CO control is pretty much
SOP; I think the IMC, or one of the codes around here, went up to
1.25 cfm/sf constant venting unless CO sensors are used; pretty much
assuring everyone uses sensors. There may still be a code req'd floor on
the min vent rate even w/sensors. And, in all but the smallest garages,
staged fans are typical. MAYBE someone could invent some rationale that
if there were some long ducts serving a deep garage, then VSD fans might have
a SLIGHTLY lower operating W/cfm and closer tracking of actual req'd
dilution air. But not by much.</DIV>
<DIV> </DIV>
<DIV>Sure it sounds like "DCV" and the PRM sez we can take credit for that;
but we would be creating a baseline considerably worse than typical
construction, even 5-10 year old construction. And certainly we can't use
0.7 W/cfm in this baseline. This is why when we get
proposals from savvy clients, they specify bldg maximum Btu/sf or
kWh/sf or emissions/sf; not some "savings" vs. an
artificial baseline. </DIV>
<DIV> </DIV>
<DIV>Fred</DIV>
<DIV> </DIV>
<DIV>P.S. Today's Puzzler: What ASHRAE PRM category does a heated parking
garage fall into? Does it matter if the heating capacity is more than the
semi-conditioned space Btuh/sf rate? </DIV>
<DIV><BR></DIV></SPAN></DIV></DIV></DIV></DIV><BR>_______________________________________________<BR>Bldg-sim
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