[Bldg-sim] Spam:Re: Process Loads?

[Marcus Sheffer]

The word “default” is unfortunate; the credit language should read “at
least”.  If your project is under 25% simply submit justification for why
you are under 25%.  The best way to do that is with a table showing the
assumed plug loads or other process loads in the facility.

 

So if you are over 25% no worries; if you are under justify why you are
under.  Don’t add process loads until you reach precisely 25% as some
projects submitting for LEED have done.

 

Regarding facilities with very high process loads pursuing LEED
certification, James is correct that this poses a major problem which the
USGBC will hopefully address this year.

 

Marcus Sheffer, Vice-Chair USGBC EA TAG

Energy Opportunities, Inc/a 7group Company

1200 E Camping Area Road, Wellsville, PA  17365

717-292-2636,  <mailto:sheffer at sevengroup.com> 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 James Hess
Sent: Wednesday, February 04, 2009 10:11 PM
To: Demba Ndiaye; Anis Ben Ayed; 
Cc: Caleb Brantley
Subject: Re: [Bldg-sim] Spam:Re: Process Loads?

 

FYI 
 our take on this issue is to document the inputs that make up the misc
equipment.  In many cases, we find that misc equipment, or “process loads”
come nowhere close to 25% of total costs.

 

For example, we are currently working on a library LEED project.  We have
very good estimates for the number of computers going into the facility, and
have estimates for students with notebook computers, printer/copiers,
breakroom equipment (refrigerator, coffee pot, etc.), etc.  You can get
energy estimates for all that stuff from EnergyStar’s website (they have
lots of good data), or take your own measurements of equipment over time
like I have ( using simple inexpensive equipment such as the “KillaWatt”
plug in 120V plug load measurement device).

 

Anyway, we document it and add all that up à comes to ~ 0.3 watts/SF, add a
schedule into our energy simulation program, and we come nowhere close to
25% of total energy costs.

 

What would we do at that point?  We have good wattage inputs based on sound
and reasonable data.  For example, a typical desktop computer will use ~ 65
watts on average.  A 22” flat panel LCD monitor will use ~ 45 watts.  So, do
you throw all those numbers out and arbitrarily increase the “watts/SF”
values until process loads = 25%?

 

Our interpretation is no.

 

Based on the following from LEED NC 2.2

 

 

 

We interpret this as we can use less than 25% as long as we document, so we
document.  We document our assumptions for process loads anyway so if it
comes out less, we’re covered.

 

We did have a project that was a flight simulator building for the US Air
Force.  The simulator equipment used a ton of energy à energy costs > 75% of
total building energy costs.  That blew the LEED savings out of the water.
Even if you assign the same load to the baseline, mathematically it’s very
difficult to achieve overall building energy savings of  14% if 75% of
energy à you can’t do anything about.  J.  In fact, we could not.

 

Just some food for thought on how we approach this area.

 

Hope this helps.

 

Regards,

 

James

 

 

James A.  Hess, PE, CEM

Energy Engineer

TME, Inc.

Little Rock, AR

ph   501-666-6776

cell  501-351-4667

jhess at tmecorp.com <mailto:email at tmecorp.com> 

 

From: bldg-sim-bounces at lists.onebuilding.org
[mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Demba Ndiaye
Sent: Wednesday, February 04, 2009 5:57 PM
To: Anis Ben Ayed; bldg-sim at onebuilding.org
Subject: Spam:Re: [Bldg-sim] Process Loads?

 

The process energy cost should compose at least 25% of the total energy
cost.

 

And yes, if you have a total cost of $1,333 then the process energy should
be >= $333.

 

_____________

Demba Ndiaye

 

From: bldg-sim-bounces at lists.onebuilding.org
[mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Anis Ben Ayed
Sent: Wednesday, February 04, 2009 6:33 PM
To: bldg-sim at onebuilding.org
Subject: [Bldg-sim] Process Loads?

 

Hi All,

 

According to the LEED NC v2.2 user manual, the default process energy cost
is 25% of the total energy cost for the baseline building. 

 

Example:

The total energy cost for a baseline building is T = (X + Process loads) 

Let’s assume that X = $1000.00 = 75% * T

 

To find the energy cost for a baseline building, we solve for T

Therefore T = $ 1000.00 / 75% = $ 1333.33

and the Process loads’ cost = 25 % * $ 1333.33 = $ 333.33

This is how I understand the 25% process load calculation.

 

Can someone please confirm this approach? 

 

Thank you,

 

Anis 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20090205/99368fc5/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 21161 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20090205/99368fc5/attachment-0001.jpeg>