[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [EnergyPlus_Support] Equipment Sizing for best savings - food for thought




Dear Jean and Jeremy,

I am keenly aware that the sizing calculations and normal conservative tendencies among engineers result in oversized equipment.  I think I recall and ASHRAE Journal article citing something like 50% (!) oversizing as common.

Engineers, however, do not size chillers with EnergyPlus.  I have assumed, though, that the energy balance calculations of E+ would result in a more realistic load peak than the typical engineer?s load calculations.

Other factors that cause a typical load calculation to produce larger values are:

·         the assumption of constant internal loads (which never happens)

·         lack of a ready means to evaluate impact of slight undersizing (e.g., What is the room temperature on a design day if I select the next smaller chiller? + .1?  +.5? +5?)

·         Unreasonable safety factors in part due to the fear Jeremy mentions about defending a smaller-than-calculated chiller size (no comment needed here other than I think the lawyers inspire more fear than they merit)




__._,_.___

Primary EnergyPlus support is found at:
<http://energyplus.helpserve.com>http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

The primary EnergyPlus web site is found at:
<http://www.energyplus.gov>http://www.energyplus.gov

The group web site is:
<http://groups.yahoo.com/group/EnergyPlus_Support/>http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.


<http://geo.yahoo.com/serv?s=97476590/grpId=3387488/grpspId=1705007389/msgId=28769/stime=1365968275>

Your email settings: Individual Email|Traditional
<http://groups.yahoo.com/group/EnergyPlus_Support/join;_ylc=X3oDMTJmYzBhNWhxBF9TAzk3NDc2NTkwBGdycElkAzMzODc0ODgEZ3Jwc3BJZAMxNzA1MDA3Mzg5BHNlYwNmdHIEc2xrA3N0bmdzBHN0aW1lAzEzNjU5NjgyNzU->Change settings via the Web (Yahoo! ID required)
Change settings via email: <mailto:EnergyPlus_Support-digest@xxxxxxxxxxxxxxx?subject=Email Delivery: Digest>Switch delivery to Daily Digest | Switch to Fully Featured
<http://groups.yahoo.com/group/EnergyPlus_Support;_ylc=X3oDMTJkdnFuMnE0BF9TAzk3NDc2NTkwBGdycElkAzMzODc0ODgEZ3Jwc3BJZAMxNzA1MDA3Mzg5BHNlYwNmdHIEc2xrA2hwZgRzdGltZQMxMzY1OTY4Mjc1>Visit Your Group  | <http://docs.yahoo.com/info/terms/> Yahoo! Groups Terms of Use  | <mailto:EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx?subject=Unsubscribe> Unsubscribe

__,_._,___