[Equest-users] Process Equipment Power Consumption

[Walson, Kristy]

Hi Omer,

On recent projects, I have had to pay more attention to the process loads for the types of equipment you mentioned below.  In the past, I would just ensure that my process energy cost was 25% of the total energy cost because I knew that the types of buildings I was modeling (commercial offices, mostly) would never have an actual process load even close to 25%.  

However, recently I have been modeling process loads in a more exact way.  What I do is I take the kW rating of the equipment, then I talk to the electrical engineer to get an idea of whether that equipment will ever run at its rated load and, if not, I apply the appropriate reduction to it based on what the electrical engineer says.  

Once I have this maximum energy use for process loads in the building, I then create a custom schedule for this process energy.  Sometimes I need to create more than one custom schedule based on the type of equipment in the space.  This can become very tedious if you get too far into the weeds, so I try to keep the schedules realistic, but simple and I keep the number of different custom schedules I create to a minimum.  As we all know, you can never know the actual occupancy and use schedule of a building until it is occupied for a certain period of time, so keep your assumptions simple and logical.

I'd love to hear what other folks are doing if it differs from my process.

Kristy Walson, PE, LEED AP
Mechanical Engineer / Sustainable Design

-----Original Message-----
From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of omoltay at mimtarch.com
Sent: Monday, May 03, 2010 1:46 PM
To: equest-users at lists.onebuilding.org
Subject: [Equest-users] Process Equipment Power Consumption

Dear All,

One of the things that cause most trouble for us in modelling is the power
consumption of equipment such as dishwashers, ovens, food warm-up
equipment and so on that have varying levels of power consumption during
operation (even PCs and laptops). We are sometimes using nameplate
installed kW values, but deep inside we know that this is quite wrong -
but we have no other more reliable source / guideline for such equipment.
I would appreciate any feedbacks on how others are modelling such
equipment.

Thank you,

Omer Moltay, LEED AP
Mimta

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG