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What sources are there for plug/equipment load assumptions for different space types?

asked 10 years ago

updated 9 years ago

If you don't have takeoffs for electric equipment/plug loads in a building, is there a source that can be used to make general assumptions for different space types?

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Isn't it too vague? Trying to address all space tyoes in one answer is a fairly tedious if not impossible job. If the question was specific to housing for example it'd be easier.

Julien Marrec's avatar Julien Marrec  ( 10 years ago )
1

I apologize if I didn't word the question very well but my intention is to find general sources like an ASHRAE Handbook or general document (COMNET for example) where I might be able to find typical equipment densities for different space types, similar to how ASHRAE 90.1 has a table of baseline lighting power densities for different space types.

Matt Larson's avatar Matt Larson  ( 10 years ago )

8 Answers

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13

answered 10 years ago

Kim Shinn's avatar

The ASHRAE 90.1 User Manual has a table of equipment power densities by space type. In the 90.1-2010 User Manual, it is table G-C. It also provides occupant densities and service hot water quantities.

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12

answered 10 years ago

Erik Kolderup's avatar

updated 10 years ago

Check out Appendix 2 of the COMNET Modeling Guidelines and Procedures. It's an Excel spreadsheet with a list of plug loads and other internal load assumptions for a range of building types. Like with any resource, use judgment regarding whether the numbers make sense for your case. But it's a good place to start. And COMNET Appendix C includes a corresponding set of schedules. See http://www.comnet.org/mgp/content/app....

I find chapter 18 of the ASHRAE Fundamentals to have some useful tables, especially for offices.

ASHRAE's Advanced Energy Design Guides are a good source of load assumptions for several building types, and they include both standard efficiency and high efficiency values in some cases.

If you're interested in internal load schedules, then check out ASHRAE research project 1093-RP. It provides hourly profiles for several building types based on some measured values. Many "default" schedules do not include realistic nighttime plug load values.

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11

answered 10 years ago

For anyone interested, the loads, schedules, and constructions for OpenStudio templates are defined this this repository:

https://github.com/NREL/OpenStudio-st...

There is a spreadsheet containing all the data and a conveinient JSON format export containing all the information (except schedules, but those will be added at some point).

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Hi Dan i would like to know if you have the source of the electric plug load source values that are on the spreeadsheet.

Julian Nino's avatar Julian Nino  ( 9 years ago )

Those values came from the DOE Commercial Reference Buildings. @aparker can give more details.

macumber's avatar macumber  ( 9 years ago )
10

answered 10 years ago

updated 10 years ago

The easiest would be to get the schedules and load profile from OpenStudio for example (from the different templates they have).

I'll answer in more detail only for housing (single home and multifamily), so it's a partial answer.

For apartments/housing, the load values and profiles in OpenStudio are derived from (Hendron, 2007), see below.

You could also try to customize it further based on the NREL research on the matter, which expands from several sources including RECS.

The Building America report has some good information for your problem starting page 36, listing a bunch of MELs (miscellaneous Electric loads) with tables of consumption per appliances and average unit/household for approx 100 MELs. The spreadsheet has the same information but allows you to see the hourly profile as well as customize the appliances you do have (In particular on tab Detailed "MEL" you can input in column D the which MELs and how many you know you have. There's also a list of sources in there, including the first one "Bob's judgment" :) )

NREL 2014 Building America House Simulation Protocols

Supporting spreadsheet (will save you some googling time if you try to locate them...) : Building America Analysis Spreadsheet for New Construction

(For reference that's where it started : Hendron, 2007: Building America Research Benchmark)

See full BLDG-SIM thread: Occupancy loads of a typical American typical family in a small container house

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That first link is broken. Here is a permalink to the document: http://www.nrel.gov/docs/fy14osti/609... (I'd edit if I could)

Eric Wilson's avatar Eric Wilson  ( 10 years ago )

Thanks for the catch. The link was OK in the post, but for some reason the site was adding some "" tags in there... Fixed it by formatting the link correctly.

Julien Marrec's avatar Julien Marrec  ( 10 years ago )
6

answered 10 years ago

I assume you're asking for US-based data sources, but for the UK there are figures available in the National Calculation Methodology (NCM) database which can be downloaded from the BRE.

Other benchmarks are available in CIBSE Guide F.

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5

answered 10 years ago

301_Hours's avatar

LEED 2009 Core & Shell has occupant and equipment densities in Appendix 1 & 2 respectively citing numerous sources for the occupancy data.

I believe the equipment loads are building level, not space level as I have never seen a laboratory with a receptacle load of 1.4 W/SF. More realistic is 6-10 W/SF at the space level.

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4

answered 10 years ago

Thom Bouriot's avatar

updated 10 years ago

If you are looking for recent UK based small power consumption I recommend you have a look at "Benchmarking Small power energy consumption in UK office buildings: a review of data published in CIBSE Guide F", it is a fairly recent research paper (2012) and includes monitored small power consumption in office buildings. I hope this helps.

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2

answered 10 years ago

In Canada the MNECB has receptacle power densities by space type.

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Asked: 10 years ago

Seen: 20,865 times

Last updated: Feb 12 '15