Small Compressed Air Analysis Tool

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Small Compressed Air Analysis Tool

• Summary of Subcommittee Meeting
• Presented to the Regional Technical Forum on
• January 6, 2008

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Background

• Compressed air savings calculator developed by
  Cascade Energy Engineering
• Proposal at the Nov 2008 RTF meeting was to allow
  the calculator to be used in lieu of more
  detailed MV to determine savings for systems
  under 75 hp
• RTF asked for real-world data to verify
  calculator works properly

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Subcommittee Meeting 12/18/08

• Attendees (conference call)
• Jeff Brooks
• Chris Helmers
• Tom Osborn
• Greg Kelleher
• Joel Jackson
• Paul Warila
• Al Frazer
• Eric Brateng
• Adam Hadley

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Subcommittee Meeting Materials

• Memo QEI Energy Management Inc (John Shinn) to
  Pacific Corp (11/13/08)
• Tool should ask for rated input bhp tool should
  include an efficiency penalty for VFDs Tool
  should correct compressors flow for operating
  pressure
• The baseline power is developed from the percent
  load with the equation of the performance curve
  for the compressor with the components for the
  equations coming from various look-up tables.
  The slope and intercepts are reasonable for the
  various compressor types. I think the author
  handled the VFD minimum power dilemma very well
• The accuracy of the tool will depend in a large
  part on the percent flow in the profile of
  compressed air demand table. My concern is that
  most plants will not be able to fill this out
  accurately. I imagine a manual of some type will
  come with the tool and the manual will provide
  some quantitative and non-quantitative methods
  for estimating these part-load values.
• Since you have a great deal riding on the users
  ability to correctly use this tool, I would not
  give it to anyone until they have had a training
  class...
• Memo EWEB Review of Regional Compressed Air
  Calculator
• We found the analysis to be generally accurate,
  but have a few comments.
• We feel the Achilles Heel of the calculator is
  the profile of compressed air demand input
  tableit is critical we find a way to reduce the
  potential for errors in the inputsways to
  mitigate this error for example training, help
  screens, user manuals.
• Its not possible to go back and estimate demand
  profiles on a compressor that has already been
  replaced. Using the monitored data to guess a
  profile would, by default, bias the results
  toward over-predicting the accuracy.
• Cascade Energy Engineerings sensitivity checks
  (next two slides)

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Sensitivity Check Inlet Mod
Provided by Cascade Energy Engineering
6
Sensitivity Check Load/Unload
Provided by Cascade Energy Engineering
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Subcommittee Recommendation to RTF

• The subcommittee believes the calculator provides
  reasonable outputs, if reasonable inputs are
  provided.  
• The RTF subcommittee recommends that the RTF
  allow the use of the compressed air tool to
  determine energy savings (in lieu of MV)
  for compressed air systems 75 horsepower and
  less.  
• The calculator should be used by qualified users
  and all calculator inputs should be reviewed by a
  utility engineer or program provider.  
• The calculator will be modified to provide space
  for the user to provide a description of how the
  "profile of compressed air demand" was derived.