Dear All,
I have a question regarding the internal load.
Under the Equipment tab of the internal load, there are two tables. One is
Equipment and another is Internal Energy Sources. For my project with a
kitchen serving 5 hours daily, how to input the power? For example, based
on the specification sheets, we have 26.5 W/sqft input power density
for electricity, and 474,000 Btu/hr for gas equipment. However, it will
make the cooling load so huge for cooling systems.
Does anyone know how eQuest convert energy input to cooling load? Did I
fill the tables right?
[image: image.png]
Thank you!
Jing
Jing:
Usually there is an exhaust hood with makeup air in the kitchen. If this is true, then you need to estimate how much heat is actually transmitted to the space compared to how much heat is expelled through the hood. This should lower your cooling load.
Paul Diglio
87 Fairmont Avenue
New Haven, CT 06513
--------------------------------------------
Subject: [Equest-users] Equipment Load
To: equest-users at lists.onebuilding.org, equest-users at onebuilding.org, equestuser00 at gmail.com
Date: Monday, December 17, 2018, 7:37 PM
Dear
All,
I have a question regarding
the internal load.
Under the Equipment?tab of
the internal load, there are two tables. One is Equipment
and another is Internal Energy Sources. For my project with
a kitchen serving 5 hours daily, how to input the?power?
For?example, based on the specification sheets, we have
26.5 W/sqft input power density for?electricity, and
474,000 Btu/hr for gas equipment. However, it will make the
cooling load so huge for cooling
systems.?Does anyone know
how eQuest convert energy input to cooling load? Did I fill
the tables right?
Thank you!Jing_______________________________________________
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
-----Inline Attachment Follows-----
Hi Paul,
Thanks for your reply. It is very helpful. Yes, we have an exhaust fan in
the kitchen, I wonder if there is an equation to estimate the cooling load
for a kitchen like this.
Jing
On Tue, Dec 18, 2018 at 6:38 AM Paul Diglio
wrote:
Hi Paul,
For our cases, we estimated 80-ish% of the heat will go right up to the
exhaust hood. So should I fill the equipment and internal energy energy
sources with the number before the 80% reduction or after? For example, I
have 10 W/sqft electricity cookers and 100,000 Btu/hr gas cookers in the
kitchen, do I fill the tables below correctly?
[image: image.png]
On Tue, Dec 18, 2018 at 6:38 AM Paul Diglio
wrote:
Hi Jing:
Yes, as long as you have documentation to back up your estimate, I would use 20% of the electrical and gas energy as being rejected in the space.? The tables look good to me.? I don't know what your schedule looks like. Attached is the COMnet schedules that are usually accepted by the rating authorities.
Paul Diglio
87 Fairmont Avenue
New Haven, CT? 06513
--------------------------------------------
Cc: equest-users at lists.onebuilding.org, equest-users at onebuilding.org, equestuser00 at gmail.com
Subject: Re: [Equest-users] Equipment Load
To: "Paul Diglio"
Date: Tuesday, December 18, 2018, 9:29 AM
Hi
Paul,
For our cases, we
estimated 80-ish% of the heat will go right up to the
exhaust hood. So should I fill the equipment and internal
energy energy sources with the number before the 80%
reduction or after? For example, I have 10 W/sqft
electricity cookers and 100,000 Btu/hr gas cookers in the
kitchen, do I fill the tables below correctly?
On Tue, Dec
Jing:
18, 2018 at 6:38 AM Paul Diglio
Usually there is an exhaust hood with makeup air in the
kitchen.? If this is true, then you need to estimate how
much heat is actually transmitted to the space compared to
how much heat is expelled through the hood.? This should
lower your cooling load.
Paul Diglio
87 Fairmont Avenue
New Haven, CT? 06513
--------------------------------------------
On Mon, 12/17/18, Jing Hong via Equest-users
?Subject: [Equest-users] Equipment Load
?To: equest-users at lists.onebuilding.org,
equest-users at onebuilding.org,
equestuser00 at gmail.com
?Date: Monday, December 17, 2018, 7:37 PM
?Dear
?All,
?I have a question regarding
?the internal load.
?Under the Equipment?tab of
?the internal load, there are two tables. One is
Equipment
?and another is Internal Energy Sources. For my project
with
?a kitchen serving 5 hours daily, how to input
the?power?
?For?example, based on the specification sheets, we
have
?26.5 W/sqft input power density for?electricity, and
?474,000 Btu/hr for gas equipment. However, it will make
the
?cooling load so huge for cooling
?systems.?Does anyone know
?how eQuest convert energy input to cooling load? Did I
fill
?the tables right?
?Thank
you!Jing_______________________________________________
?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
?-----Inline Attachment Follows-----
Great thread!
@Jing: You definitely have some options in terms of how you use the inputs to account for installed vs. "thermally incident on the space" energy. I personally prefer to use the "Input Power" field to represent the maximum "installed" watts/gas input, then use the "fraction to space" to capture how much isn't carried away by the hood(s). From there, the associated fractional schedule(s) will dictate both what is seen over time at the meter and in the space.
@All: The COMnet appendix C schedules don't appear at my first glance to expressly cover kitchen equipment profiles, but rather appear to "dodge" the issue with the statement for refrigeration/gas equip of "COMNET defaults are based on continuous operation." Perhaps digging into those defaults might reveal some effective FLE hours of operation for a given kitchen? Another avenue may be to research whatever current operational schedule guidance might via Fisher-Nickel (Fishnick) for LEED prescriptive measures - resources I believe are linked from here: https://fishnick.com/design/resources/leed/
~Nick
Nick Caton, P.E., BEMP
? Senior Energy Engineer
? Regional Energy Engineering Manager
Energy and Sustainability Services
? Schneider Electric
D??913.564.6361
M??785.410.3317
F??913.564.6380
E??nicholas.caton at schneider-electric.com
15200 Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States
I also find it difficult to track down actual operating schedules for kitchen cooking and refrigeration appliances. One source I lean on is the Commercial Building Reference Models and the technical support documents from creating those models. The technical support document provides the schedules used for the kitchen equipment loads and the internal loads for various building/space types:
https://www.nrel.gov/docs/fy11osti/46861.pdf
Christopher R Jones, P.Eng.
T+ 1 416-644-0252
Thank you Nick. Yes, after trying different ways, I realized that fill ?
Input Power? is better than per area. I assumed 20% of the input power
would be converted to heat gain. And 80% for sensible, 20% for latent. In
that case, the fraction I filled in the eQuest was 0.16 for sensible HG and
0.04 for Latent HG. Does that make sense?
Jing
On Wed, Dec 19, 2018 at 10:09 PM Nicholas Caton <
It does make sense!
In support of the limits for my brain?s memory capacity, I like to insert that sort of algebra to distribute your input assumptions into the fields as a local expression to retain the logic for me in lieu of separate development notes outside the model.
~Nick
[cid:image001.png at 01D49858.3EEBECE0]
Nick Caton, P.E., BEMP
Senior Energy Engineer
Regional Energy Engineering Manager
Energy and Sustainability Services
Schneider Electric
D 913.564.6361
M 785.410.3317
F 913.564.6380
E nicholas.caton at schneider-electric.com
15200 Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States
[cid:image002.png at 01D49858.3EEBECE0]
I typically use 85% of the heat is captured by the hood assuming that the hood is design correctly and sufficiently extends beyond the cooking surface. If it's an existing kitchen, then it maybe less. ASHRAE Applications has some information, but the hood manufacturer and/or kitchen consultant should have a project specifc capture efficiency.
Also, not all of the equipment load is under a hood so you may want to look at the kitchen layout and prorate accordingly.
Also, don't forget to put the rest of the energy directly on the electric and gas meter.
You still have 26.5 W/ft2 of consumption so 80-85% of that needs to go directly on the meter just like exterior lights would with the same kitchen schedule. Same goes for the natural gas.
Hope that makes sense.
Fred
FRED BETZ? PhD, LEED? AP BD+C
BUILDING PERFORMANCE
AEI | AFFILIATED ENGINEERS, INC. ?
5802 Research Park Boulevard | Madison, WI ?53719
P: 608.236.1175 | F: 608.238.2614??
fbetz at aeieng.com? |? www.aeieng.com ?
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