Deemed Savings Update: ECMs in Display Cases

Ben Cartwright

PECI

January 5, 2009

Acknowledgements

We would like to thank the following utilities for support• BPA• PSE• AVISTA

Purpose

Deemed measure approval•Updated savings for ECMs in refrigerated display cases

Measure Name•Shaded Pole to ECM in Refrigerated Display Cases

Agenda

BackgroundDescription of Measure

History

Energy SavingsSummary of Analysis

Analysis Methodology

Findings

Calculation Methodology

PECI Experience / Market

ResultsCurrent Savings

Revised/Proposed Savings

Cost

Measure Life

Technical and Program Specifications

Conclusion

Background

Description of Measure:• Replace standard efficiency shaded pole motor with ECM in

refrigerated display cases◦ Savings from reduction in input wattage (direct/auxiliary

savings)◦ Savings from reduction in heat load with ECM replacement

(refrigeration savings)

Background

History:• RTF updated savings SP- ECM in Walk-Ins (3/09)

◦ Weighted motor wattages based on size from market data◦ Weighted case temperatures based on audit data◦ Deemed kWh savings increase of 50%

• Proposing savings for Display Case SP to ECMs using same approved methodology

• Summit Blue Energy Smart Grocer program evaluation: 469 kWh

Energy Savings

Summary of analysis:•Reviewed base case and efficient case wattages•Analyzed existing historical data vs. “real world” data•Revised savings

Energy Savings

Description of Energy Savings Methodology•Issue: Current savings use 100% 9 watt output – research indicates

larger motors in the mix•Review and research motor data• Manufacturer’s data: Tyler, Hussmann, GE• GrocerSmart© database store audits• Invoices from installed measure and audit data• Established ranges:

• HP mix (establishes wattage for direct/aux. savings)

• Case temperature mix (establishes refrigeration savings)

Energy Savings

Findings – Motor HP Mix:

• Motor HP market based on actual invoices◦ 3,652 installed motors from 46 different sites, as invoiced

» 3,328 motors: 9 watt (91%)» 122 motors: 16-23 watt (3%)» 202 motors: 37 watt (6%)

Energy Savings

Findings – Case Temperature Mix• Case mix temperature data

◦ Grocery store audit data: 223 Stores; 23,986 motors» 67% medium temp (16,071 motors)» 33% low temp (7,915 motors)

Energy Savings

Calculation Methodology

• Direct/Auxiliary Savings

◦ (Baseline Input Watts) – (Efficient Case Input Watts)

◦ Motors run 8760 hours for medium temp◦ Motors run 8395 hours for low temp (1 hour/day defrost)

hrskWW

WattsWattskWhfan efficientbaseline 8760

/1000

Energy Savings

Calculation Methodology• Refrigeration Savings

◦ Full Load Hours (FLH) higher for low temp cases◦ “System” Energy Efficiency Ratio (EER) lower for low temp cases◦ Degradation Factor (DF) is .98 = condenser degradation penalty

casesall

i DFEER

FLHkWBTUhrskWhfankWhfanFanskWh

*

/413.3*)8760/(

Energy Savings

Calculation Methodology Conclusion• Direct/Auxiliary savings increase due to the added mix of larger

motors• Existing case temperature mix confirmed from additional analysis

Results

Current SP to ECM Measure Energy Savings• Existing measure savings based on:

◦ 9 watt motor only ◦ Medium and low temp cases mix (69%/31%)◦ 337 kWh/motor

Measure

Baseline Fan Watts (Shaded

Pole)Efficient Fan

Watts kWh Energy Savings

9 Watt Output Input Watts Input Watts kWh/motor

Med/Low Temp Shaded Pole to ECM in display cases 49.8 16.9 337

Results

Revised/Proposed Energy Savings:• Increased pre (base case) and post (efficient case) wattage based

on market audit data using◦ Weighted blend of wattages (direct/auxiliary) savings

» 9 watt (91%), 16-23 watt (3%), 37 watt (6%)◦ Display case temperature weighted blend (refrigeration)

savings» 33% low temp» 67% medium temp

Results

Revised/Proposed Energy Savings:• New kWh based on weighted blend of motor wattages and case

temperatures:◦ 453 kWh/motor

EnergySmart Measure Unitized or

Modeled Savings

Unit of measure

Demand Savings

(kW)

Energy Savings (kWh)

Measure life

Total Measure

Cost (2007)

Measure Cost Source

Lost Opportunity Measure

RTF B/C Ratio

Shaded Pole to ECM in Display Cases Medium and Low Temp

Unitized motor 0.0740 453 15 110.00$ Program

dataN TBD

Cost Assumptions/Data

• Current Full Measure Cost: $110/motor• Equipment cost confirmed from submitted PNW invoices

◦ 9 watt: $48/motor average◦ 16-23 watt: $46/motor average◦ 37 watt: $50/motor average

• Labor cost confirmed from PNW invoices and industry research◦ PNW: $50/motor◦ PG&E SP to ECM 2008 deemed measure workpaper

» $41/motor◦ Southern California Edison SP to ECM 2007 workpaper

» $36.45/motor

Measure Life Assumptions/Data

• Measure Life/Effective Useful Life is 15 years◦ Southern California Edison1, PG&E2 and BPA3 program all use

15 year measure life for ECMs» 1Energy Savings Potential for Commercial Refrigeration Equipment.

June 1996. U. S. Department of Energy. Arthur D. Little. p 5-51» 2CALMAC Protocols, Appendix F, Effective Useful Live Values for Major

Energy Efficiency Measures, September 2000» 3Council Plan 1996; 15 year EUL used for all Retrofit HVAC Systems &

Controls including motor retrofits

Technical/Program Specifications

• Terms and Conditions: ECMs replace shaded pole fan motors in refrigerated display case

◦ “Applicable to existing standard efficiency shaded pole evaporator fan motor for refrigerated display cases. Shaded pole motors must be replaced by electronically commutated motors (ECMs). Incentive is based on number of ECMs installed.”

Conclusion/Summary

• Increased kWh savings requested based on:◦ Installed motor mix of motors > 9 watts

» Based on actual PNW program invoices

◦ Weighting of medium temp vs. low temp cases» Based on actual GrocerSmart audit data

• Approval for deemed kWh savings of 453 kWh/motor