Green Motor Rewinds UES Measure Update

1. Green Motor RewindsUES Measure Update Industrial & Agricultural Motors April 16, 2013

2. Reason for bringing back to RTF • RTF voted to adopt updated measure savings in December, 2012 • Informed that one recommendation from October, 2012 review was not incorporated • The UES assumes NEMA premium efficiency for the measure motor efficiency, however an average efficiency rating consistent with motors processed through the program should be determined and used instead. • RTF voted to review data on efficiency weights

3. HP x 0.746 x OP x ML HP x 0.746 x OP x ML Unit Energy Savings (kWh/yr) = Baseline Eff. Efficient Case Eff. Savings Estimation Equation Where: • UES - Unit Energy Savings is the annual energy savings of the motor in kWh by retaining original efficiency utilizing rewind process control • HP - Horsepower obtained from standardized horsepower ratings • 0.746 – Converts horsepower to kilowatts • OP - Operating hours is the annual operating hours of the motor • ML - Motor loading is the percentage of the standardized horsepower rating required to drive equipment • Baseline Eff. – Nameplate motor nominal efficiency without process control (i.e. range of 0.5% - 1% less than Efficient Case) • Efficient Case Eff. – Nameplate motor nominal efficiency with process control

4. Changes made to Workbook • Open Workbook • Clarified analysis method on Summary Tab • Corrected source documentation for efficient case • Incorporated GMPG data tables for efficiency values at each HP • Added references to for Pre-EPAct, EPAct and NEMA Premium efficiency tables • Removed analysis for motor sizes <15 HP as GMPG does not offer these

5. Methodology • Current Methodology: • Use NEMA Premium as the Efficient Case motor efficiency • (i.e. all motors entering GMPG are NEMA premium efficiency) • Conservative estimate from initial measure development in 2007 • Proposed Methodology: • Develop estimate of Efficient Case motor efficiency weightings for each HP size based on count of motors entering program

6. Proposed Method Data Sources • GMPG efficiency data collected from historical program participation by motor size • N=2337 motors from program years 2008-2012 • Pre-EPAct motor efficiency • MotorMaster database • Conversation with Gil McCoy at WSU indicated efficiencies for pre-1989 motors were based on ~10,000 motors available at that time • Un-stamped nameplate indicates a Pre-EPAct motor • EPAct and NEMA Premium motor efficiency • Published efficiency tables from DOE

7. Weightings table* *Represents number of motors collected during program years Sept. 2008 – Aug.2012

8. Decision needed • SBW recommended that an average efficiency rating consistent with motors processed through the program should be determined and used instead. • Question: Is the weighting methodology and GMPG program data sufficiently reliable to use for this estimate?

9. Revised Savings

10. Revised Savings

11. RTF Proposed Motion: I ______________ move that the RTF incorporates the motor efficiency data and sources presented , updates the UES savings values for both Industrial and Agricultural Green Motor Rewinds, and moves the measures from “Under Review” to “Active” status.

12. Reference Only - December 2012 RTF Presentation Back-up slides

13. Green Motor Rewinds MeasureClassification and Properties

14. Green Motor Rewinds Summary of Actions to Date 1Cascade Energy, presentation to the RTF on super high efficiency motors. November 14, 2012.

15. Green Motor Rewinds Summaryof Actions to Date (Continued)

16. Green Motor Rewinds Discussion Item: Additional Measure Categories Navigant does not recommend extending motor rewind categories to differentiate between motor type (ODP/TEFC) or motor speed (1200-3600 RPM), as these have a minimal effect on overall savings. (Note: This would also add an additional 360 measure line items).

17. Green Motor Rewinds Discussion Item: Industrial Motor Loading and Op Hours • NW Industrial Motor Database load factors were collected through different methods including metering/calculating, self-reported, and estimated based on end use. Reported motor load estimates do not account for idle time. • Cascade Energy RTF presentation found minimal correlation between size, op hours and end use in the NW Industrial Motors Database.1 Table below shows current industrial motor estimates. 1Cascade Energy, presentation to the RTF on super high efficiency motors. November 14, 2012.

18. Green Motor Rewinds Discussion Item: Standard Rewind Efficiency Degradation • MotorMaster’s default standard rewind efficiency degradation (0.5 – 1%) is primarily based on 2003 EASA lab test of six motors between 100 and 150 HP.1 • Lab test showed efficiency degradation from non-process controlled rewinds of 0.3 to 1% (with an average of 0.6%). • The 2003 EASA study, in conjunction with the MotorMaster default assumption (which is also based on EASA) was previously used as the RTF’s standard efficiency rewind degradation assumption. • GMPG submittal provided a second study by the Association of Electrical and Mechanical Trades (AEMT) of much smaller motors (7.5 HP) showing efficiency degradations between 0.5 and 3%. 2 • Studies of efficiency degradation for motors larger than 150 HP are unavailable. • Studies of efficiency degradation comparing motors in the field or program/non-program participants are also unavailable. 1EASA/AEMT (2003). The Effect of Repair and Rewinding on Motor Efficiency. 2 AEMT (1996). The AEMT Good Practices Guide – Appendix 2: Burn-out Ovens and Their Effect on Stator Core Losses.

19. Green Motor Rewinds Do the Studies Used for Standard Rewind Efficiency Degradation Meet One of the Allowable Proven UES Estimation Procedures? • Procedure 1: Statistical (Section 3.1.1, pg. 8 of the guidelines) • “The UES estimate may be derived from statistical analysis of baseline and efficient case energy use.”* • Navigant’s recommendation: Does not meet guidelines • Neither the 2003 EASA study nor the 1996 AEMT study were designed to provide statistical samples of a population. • To use either of these studies as the statistical sample of the NW motor rewind population is not statistically justifiable. • Procedure 2: Meta-Statistical (Section 3.1.2, pg. 9 of the guidelines) • “In some cases, relatively small statistical studies are conducted by a number of different agencies. None of these studies alone provide sufficient confidence in the UES estimate. However, the RTF may determine that a value in the range of savings demonstrated by these studies constitutes a sufficiently reliable estimate.”* * Regional Technical Forum (RTF). Guidelines for the Development and Maintenance of RTF Savings Estimation Methods. June 1, 2011.

20. Green Motor Rewinds Do the Studies Used for Standard Rewind Efficiency Degradation Meet One of the Allowable Proven UES Estimation Procedures? • Navigant’s recommendation: RTF needs to decide if these studies qualify as meta-statistical per the guidelines • The provided motor rewind studies are not “statistical studies” in the sense that the motors tested were not designed be a statistical sample of a population. • If the studies are considered to be “statistical studies,” the RTF could determine a “sufficiently reliable estimate” from these studies – which in the case of standard motor efficiency degradation would be some value between 0.3 and 3% (with an average closer to 0.6%). • Procedure 3: Calibrated Engineering (Section 3.1.3, pg. 9 of the guidelines) • “UES may be estimated with calibrated engineering procedures… Calibrated engineering estimates may be based on measurement and modeling of savings for randomly selected end users. Alternatively, they may be any group of program participants, if the RTF determines that the group is sufficiently representative of likely future participants.”* * Regional Technical Forum (RTF). Guidelines for the Development and Maintenance of RTF Savings Estimation Methods. June 1, 2011.

21. Green Motor Rewinds Do the Studies Used for Standard Rewind Efficiency Degradation Meet One of the Allowable Proven UES Estimation Procedures? • Navigant’s recommendation: RTF needs to decide if this study qualifies as a calibrated engineering study per guidelines • It does not appear that the provided studies use “randomly selected end users” or “program participants” for the motors tested. • The GMPG submittal references The Canadian Standards Association (CSA) Standard C392-111, which may be able to assess savings of this measure going forward, in conjunction with additional data; however, collecting the data would be difficult. • C392-11’s foreword states, “This Standard provides guidance to electric motor service centers in verifying that the refurbishing process has maintained or enhanced the electric motor (hereafter motor) efficiency. It is also intended to provide a reliable evaluation of changes in the condition of the motor, with respect to its efficiency that might have resulted from its failure…” 1Canadian Standards Association (CSA). Standard C392-11, Testing of three-phase squirrel cage induction motors during refurbishment. 2011.

22. Green Motor Rewinds Energy Savings Results Comparison – Industrial Sector

23. Green Motor Rewinds Energy Savings Results Comparison – Industrial Sector

24. Green Motor Rewinds TRC Comparison – Industrial Sector

25. Green Motor Rewinds Energy Savings Results Comparison – Agricultural Sector

26. Green Motor Rewinds Energy Savings Results Comparison – Agricultural Sector

27. Green Motor Rewinds TRC Comparison – Agricultural Sector