[Bldg-sim] Energy Model Cost - best design doesn'tequalmost LEED points

David Eldridge dse at grummanbutkus.com
Sun May 15 14:52:05 PDT 2011


I’m not sure it is a completely fair comparison straight up – many of the
LEED for New Construction projects that I see have extremely high demands
and expectations from their owners about productivity and features.  Many of
these that I have experience with are healthcare, higher education, and
laboratories, which as Julia B. mentioned have a huge impact from the
operational characteristics that can be influenced at the time of design,
but are only partially inside the sphere of influence for the architect and
engineers as the building operates.  Also lots of commercial high rises for
banking institutions with heavy computer loads.



Especially as the energy code squeezes the “regulated” energies down to
lower and lower levels, the process energy usage becomes a greater percent
of the total which could be a major factor in why many of the buildings from
the study weren’t performing as modeled – the energy end-use that is the
least influenced by the design team is becoming a larger percentage of the
total.



Since the energy savings percentage currently utilized is a relative
baseline, you may see some variations in absolute EUI between two
neighboring properties – in fact I’d expect it!  If a building was going to
be required to save 10% versus 90.1 and a peer building was built nearby
that was “equal” to 90.1, the variances in the process loads, system
mapping, building geometry, occupied hours, etc. could be just as important
variables than LEED registration or non-registration to determine which had
a higher EUI than the other.



It will be very difficult to account for the geometry and occupancy
variables when determining the proposed target EUIs.  Also how to even
choose the metric as a basis between site, source, energy cost – this is
going to be very difficult to implement.  What about the Durst Organization
building that has cogen, heat recovery for absorption, and thermal
storage…definitely won’t fit this target EUI mold, but overall the
strategies were recommended and implemented by a savvy owner.



Specifically about the “famous study” I could also make an argument that
relating to energy usage, there are certainly many designers (many of
ourselves on this list I hope!) that work on projects where we’re using
efficient systems and equipment as the basis regardless of LEED registration
– who is to say that an owner can’t make an initiative for an energy
efficient building without LEED certification?   90.1 and IECC have been
advancing quickly, and even the code minimum building built today should be
a pretty good performer.



So to make a long story short, I think the idea of having the EUI
conversation is good and agree that any EUI target would have to be subject
to adjustment, and that more emphasis/incentive should be placed on the EBOM
rating system as a tool for improving the operations of the buildings for
the remainder of their lifetimes.  I don’t see how EUI targets will work in
a formulaic/prescriptive way as part of a LEED credit or prerequisite in
place of the relative baseline we use now without a major change in how the
project is approached from the owners.  The larger goals should be
achievable without this step in my opinion, and having the discussions on an
individual project basis.



David



*
*



David S. Eldridge, Jr., P.E., LEED AP BD+C, BEMP, BEAP, HBDP

*Grumman/Butkus Associates*

*
*





*From:* bldg-sim-bounces at lists.onebuilding.org [mailto:
bldg-sim-bounces at lists.onebuilding.org] *On Behalf Of *Hussein Abaza
*Sent:* Saturday, May 14, 2011 7:47 PM
*To:* sheffer at energyopportunities.com
*Cc:* bldg-sim at lists.onebuilding.org
*Subject:* Re: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points



There is a famous study ( I don't recall the link to it) which shows that
almost 50% of LEED buildings consume as much and more energy than non LEED
buildings.
----- Original Message -----
From: "Marcus Sheffer" <sheffer at energyopportunities.com>
To: "Julia Beabout" <juliabeabout at yahoo.com>, "Nick Caton" <
ncaton at smithboucher.com>, "Hussein Abaza" <ahussein at spsu.edu>, "Bill Bishop"
<wbishop at pathfinder-ea.com>
Cc: bldg-sim at lists.onebuilding.org
Sent: Saturday, May 14, 2011 4:36:22 PM GMT -05:00 US/Canada Eastern
Subject: RE: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points


The primary purpose is to get the conversation started, early.  It is an
opportunity to educate the owner and the team about energy.  In my
experience the majority of designers can’t even tell you the metric for
comparing building energy consumption.  I have often had this conversation
early in the project design and have been met with blank stares.  It is
incumbent upon us who do understand these energy issues to get the
conversation started.  Caveat the heck out of the goal, explain the
limitations, discuss the relative vs absolute metrics, be open about the
issues – so that we can raise awareness one conversation at a time.  This is
the power of a market transformation tool like LEED.  It enables us to have
these conversations.



I agree that both of these items are potential issues, talk to your clients
about them.  If you don’t have a goal, how do you measure success?



Marcus Sheffer

Energy Opportunities, Inc/a 7group Company

1200 E Camping Area Road, Wellsville, PA  17365

717-292-2636, sheffer at sevengroup.com

www.sevengroup.com



*From:* Julia Beabout [mailto:juliabeabout at yahoo.com]
*Sent:* Saturday, May 14, 2011 9:57 AM
*To:* Marcus Sheffer; Nick Caton; Hussein Abaza; Bill Bishop
*Cc:* bldg-sim at lists.onebuilding.org
*Subject:* Re: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points



While I conceptually agree with and understand the kbtu or watts/sf
approach, to me, there seems to be some series issues with it in reality.

First, I don't agree that generating or coming up with appropriate target
values during design is always (or even frequently) an easy thing to do or
easy data to find.  It depends on your bldg type.  I do a lot of labs and
hospitals.  Manufacturing and industrial use bldgs can have the same
issues.  Good EUI data is not easy to come by for these bldg types - partly
because the user equipment that is installed in them can be a big portion of
the energy demand and consumption and it's always changing and can be very
specific to each client.  For example: is it a community hosptial with more
modest and generic care provide?....a state of the art hospital with
specialized care functions?....does the lab have primarily biology or a
chemistry functions....etc etc.  These things all affect the EUI.  In my
opinion, the best resource for this data is actually utility companies based
on data from similar customers, but that data is not generally publicly
available and/or the population of similar comparable buildings may be small
and difficult to relate to your bldg.

Second, quite frankly, in my opinion, DESIGN phase energy models are poor
predictors of ACTUAL bldg energy use.  They are best at predicting RELATIVE
(comparative) energy use.  This is not because the tools are not good or
inaccurate but because we and the owners are so poor at predicting how the
bldg will actually be used, weather, etc.  One additional factor, is what
equipment will actually be installed.  It's not uncommon for the technology
to have changed bewteen the time that we start design and the time the
equipment is actually purchased closer to the end of construction.  All
these things effect not only the equipment w/sf usage but the ac w/sf usage
etc.   So, there seems to me to be a serious disconnect to me if we talking
about setting energy targets during DESIGNbased on statistical data of
ACTUAL energy use and trying to use those figure during the design phase for
predicted energy use.  Again, I love the idea but are we really there yet in
reality.  It seems to me we need a lot more data that doesn't exist yet -
and mechanism to collect that data.  (CBECS etc are good, but the population
and variability for bldgs of these types has a long way to go).

I missing something about what's being proposed/talked about?




------------------------------

*From:* Marcus Sheffer <sheffer at energyopportunities.com>
*To:* Nick Caton <ncaton at smithboucher.com>; Hussein Abaza <ahussein at spsu.edu>;
Bill Bishop <wbishop at pathfinder-ea.com>
*Cc:* bldg-sim at lists.onebuilding.org
*Sent:* Fri, May 13, 2011 7:01:25 PM
*Subject:* Re: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points

First of all the goal is not at all arbitrary but must be based on an
expected outcome within a reasonable expectation.  It is informed by data
from similar, actual building energy consumption.  I don’t think I need to
explain the tools one can use to do this.



Your goal (do the best you can) sounds like, “let’s build an energy
efficient building”.  This is meaningless.  Energy efficiency in the context
of new construction is always relative and without a quantification of what
energy efficient means this is no goal at all.



Like any early stage performance goal the number is adjustable as more is
discovered in the design process.  If the target is later discovered to be
unreasonable due to a wide range of potential issues, then the target is
adjusted.



If you pick your EUI goal the way you describe then yes this is a worthless
goal but the key point is that it is never selected arbitrarily.



Marcus Sheffer

Energy Opportunities, Inc/a 7group Company

1200 E Camping Area Road, Wellsville, PA  17365

717-292-2636, sheffer at sevengroup.com

www.sevengroup.com



*From:* Nick Caton [mailto:ncaton at smithboucher.com]
*Sent:* Friday, May 13, 2011 6:17 PM
*To:* Marcus Sheffer; Hussein Abaza; Bill Bishop
*Cc:* bldg-sim at lists.onebuilding.org
*Subject:* RE: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points



Not to be a jerk, but to ask an honest question: what is the point?  I’ve
been involved with “established energy target” projects and never really
picked up on the logic behind it – I would appreciate a layman’s
explanation.



Put another way:  If you select an arbitrary EUI or watts per square foot at
the earliest stages of design, what have you gained in design process?
If/when a project “meets the goal” mid-design, are future design decisions
supposed to de-emphasize energy impact (no!)?  If on the other hand, a
project finds that target unreasonable down the road, what then?



Not setting a mile-marker like this implies designing the best building you
can given the time/budget available and any other constraints… that seems
more likely to result in the best end-result to me.



To draw analogy, if design of a LEED (or any energy-conscious) project is
like planning a road trip from Kansas to Florida, setting EUI goals seems
something like choosing a rest stop by throwing a dart at the map
blindfolded.  It doesn’t help you get to your destination any more
efficiently, it may be far out of the way, and now you’ve got a hole in the
wall… what was the point?



Okay, maybe a weak analogy – chalking it up to a very long week =).
Honestly, I’d appreciate someone laying the value behind this approach – I’m
expect the logic does exist, and I just haven’t yet seen the light!



~Nick



[image: cid:489575314 at 22072009-0ABB]

* *

*NICK CATON, E.I.T.*

PROJECT ENGINEER

Smith & Boucher Engineers

25501 west valley parkway

olathe ks 66061

direct 913 344.0036

fax 913 345.0617

www.smithboucher.com* *



*From:* bldg-sim-bounces at lists.onebuilding.org [mailto:
bldg-sim-bounces at lists.onebuilding.org] *On Behalf Of *Marcus Sheffer
*Sent:* Friday, May 13, 2011 4:36 PM
*To:* 'Hussein Abaza'; Bill Bishop
*Cc:* bldg-sim at lists.onebuilding.org
*Subject:* Re: [Bldg-sim] Energy Model Cost - best design doesn'tequalmost
LEED points



Agreed.  The new credit language for the next version of LEED does ask
project teams to establish an absolute performance goal.



Marcus Sheffer

Energy Opportunities, Inc/a 7group Company

1200 E Camping Area Road, Wellsville, PA  17365

717-292-2636, sheffer at sevengroup.com

www.sevengroup.com



*From:* bldg-sim-bounces at lists.onebuilding.org [mailto:
bldg-sim-bounces at lists.onebuilding.org] *On Behalf Of *Hussein Abaza
*Sent:* Friday, May 13, 2011 10:15 AM
*To:* Bill Bishop
*Cc:* bldg-sim at lists.onebuilding.org
*Subject:* Re: [Bldg-sim] Energy Model Cost - best design doesn't equalmost
LEED points



Could any one advice why LEED would not put the base design as Watt per
square foot, or per occupant, or per hotel bed etc. so the Architecture
becomes more innovative early in the design to save energy?
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