Grocery Measure: EC Motors for Display Cases Regional Technical Forum July 21 st, 2015 Mohit Singh-Chhabra.

Grocery Measure: EC Motors for Display Cases

Regional Technical ForumJuly 21st, 2015

Mohit Singh-Chhabra

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Presentation Objectives

• Approve proposed measure analysis • Change measure category to Small Saver

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Measure Background

• Measure Name: Grocery: EC Motors for Display Cases

• Current Measure Category: Proven

• Proposed Measure Category: Small Saver

• Current Measure Status: Active

• Proposed Measure Status: Active

• Measure Sector: Commercial

• End Use: Grocery- Refrigeration

• Current Sunset Date: August, 2015

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Staff Highlighted Area

• Use of multiple savings and cost streams over measure life (and beyond)– Applies to all pre-conditions measures with RUL <

EUL• Applying Risk Mitigation Credit to savings that

persist through planning horizon

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What is this measure?

• Replace Shaded Pole motors with EC (Electronically Commutated) Motors driving the evaporator fan for grocery display cases

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How is energy saved?

• EC Motors are more efficient (~66%) than Shaded Pole (~20%) – More efficient EC Motor generate less heat• less interaction with the refrigeration system

• Although these motors are small (<1 HP), they run all year long (8760 hours)

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Proposed Measure Category: Small Saver

• Total savings claim calculated using CLEAResult (PECI) motor install count since mid-2013 is 0.14 aMW– Bonneville estimates approx. 1 aMW remaining savings

potential for all motor measures in grocery stores in its territory • Grocer Market Opportunity Assessment (6/13) study conducted by

Cadmus• Note: Other RTF Grocery Motor measures are categorized as small

savers as well (ECMs for walk-ins, Compressor head fan motor retrofit)

• Uncertainty in motor efficiency and EER values used for analysis

• CAT proposal: update measure category for ECM in Display Case to Small Saver

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Engineering Analysis Details

• Energy savings calculated as follows:

– fan kWh savings component is a result of motor upgrade

– the other part of the formula accounts for interactive effects with the refrigeration equipment

fan * Annual Hours

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Data Used to Update Measure

• CLEAResult provided CAT with data on EC Motor installs in display cases starting in mid-2013– Motor count

• 32 different motor models, ~1800 total

– Rated watts– Installed cost/ motor– Install date and other relevant fields

• Recent data show higher average installed motor watts than existing estimate– Expect savings to go up

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Key Energy Savings Calculation Parameters

• Motor Efficiency: No Change• Operating Hours: Minor Change

– CAT Proposal: 8760 operation• Current workbook assumes that LT evap. fan motors are turned off

during defrost– CAT did not find documentation of defrost cycle hour estimate

• DOE TSD uses 8760 as operating hours

• EER of refrigeration system: Change, updated using SIW– MT EER = 11– LT EER = 4

• Baseline: Change– This is a pre-conditions measure with RUL<EUL. Baseline

changes over measure EUL

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Measure Lifetime• EUL = 15 years (DEER)• RUL needs to be estimated for pre-conditions– DEER provides estimate of 5 years– DEER assumption: RUL = EUL/3– CAT proposal to go with that. Reasonable assumption

• Assumption: In the counterfactual, at the end of RUL SP motor would be replaced by a current practice motor– Combination of shaded pole and EC Motor. As per CBSA,

ratio of all SP to EC Motors is 84% to 16%• Full savings and cost assigned during RUL period• Reduced savings and cost assigned for remaining EUL period

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Energy Savings Streams

0

100

200

300

400

500

600

700

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

kWh

Savi

ngs

Year

These savings (685 kWh) realized through

the SP RUL

These savings (484 kWh) persist

through the EUL

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First Year Energy Savings Comparison

Existing Proposed0

100

200

300

400

500

600

700

800

kW

h

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Risk Mitigation Credit

A Risk Mitigation Credit is applied to measures that save energy throughout the 20 year planning horizon – Credit for long term resource procurement risk reduction

• Risk Mitigation Credit is applicable to:– savings that have the potential to recur/ renew or– savings that are long term (>20 years). E.g., insulation

• Risk Mitigation Credit is not applicable to:– Savings built into the load forecast. i.e. Short term savings that do

not renew• E.g., Early retirement savings• E.g., Savings subsumed by upcoming Codes & Standards

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Risk Mitigation Credit (Contd.)

• Proposal is to not include Risk Mitigation Credit for early retirement portion of savings– Assign Risk Mitigation Credit to Current practice savings

0

100

200

300

400

500

600

700

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

kWh

Savi

ngs

Year

Current Practice Savings (Red) get Risk Mitigation Credit

No Risk Mitigation Credit for Early Retirement Savings (Green)

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Incremental Cost: Early Replacement Methodology

• The initial cost (first year cost) incurred is the full cost of the EC Motor

• The customer, by installing an EC Motor today, avoids cost of a new “Current Practice” motor RUL (5) years from now.– This negative cost (credit) is accounted for as a non-

recurring periodic cost in ProCost• The period of analysis is the EUL of the EC Motor (15

years). The Current Practice motor would have some monetary value at the end of EC Motor EUL– This value is accounted for in the cost-benefit analysis

17 Incremental Cost: Early Replacement MethodologyMimics calculations ProCost uses where costs or benefits are truncated by program life

Notes: All costs are in 2006$’s.

• Average weighted EC Motor installed cost = $83• Current Practice Motor Cost = $66

– Equates to equal annual payments of $6 through EUL, assuming• EUL (new unit): 15 years• Real Discount Rate: 5%

• PV Lifetime Measure Cost = $EC Motor – Sum(Red Bubble)

$-

$1.00

$2.00

$3.00

$4.00

$5.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

PV Annual Payments (in the Counterfactual) for a Current Practice Motor

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Incremental Cost Results

Existing Proposed $-

$10

$20

$30

$40

$50

$60

$70

$80

$90

$83 is the first year incremental cost

$45 is the PV incremental cost over the lifetime

Note: Costs are in 2006$

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Cost Effectiveness (TRC) Results

0

2

4

6

8

10

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Existing Proposed

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Delivery Verification Guidance

• Measure Identifier: Check motor installed is an electronically commutated motor

• Savings Baseline (Pre-Conditions): Check measure replaced a shaded pole motor

• Consistent with what was adopted for Walk-Ins on May’15 Meeting

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Decision Slide

• “I __________ move the RTF approve the Display Case EC Motors measure as presented and:– Set the Category to ‘Small Saver’;– Set the Status to ‘Active’;– Set the sunset date to March, 2019.”

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Additional Slides

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Key Assumption: Motor Efficiency

EC Motors are assumed to be 66% efficient, SP Motors are assumed to be 20% efficient• Source: US DOE Report: Energy Savings Potential and

Opportunities for High-Efficiency Electric Motors in Residential and Commercial Equipment (December, 2013)

• Same as existing workbook

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Key Assumption: Annual Hours of Operation

• Proposed Assumption: 8,760 Hours (motors operate all year round)– Reason: evaporator motors in refrigerated display

cases operate continually to:• circulate cold air in the case and • Develop an air curtain in open display cases• Similar to current assumption

– US DOE Technical Support Document for Commercial Refrigeration also advises that these motors run continually

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Key Assumption: EER of Refrigeration System

• The following EER values were adopted based on PECI EER analysis presented to the RTF on 3/14:– Medium temperature cases EER = 11 – Low temperature cases EER = 4

• Decision: RTF approve the EER analysis as presented and, following a diligent review by the Grocery Subcommittee, include the final EER results table in future updates of the Standard Information Workbook for use in UES measure assessments.– A review of the EER analysis measure spreadsheet conducted, the DOE

2R models used to generate data for the spreadsheet were not reviewed

– Measure is proposed as a Small Saver, CAT recommends these updated EER values be used, if RTF decides to review the DOE 2R models, the EER values will be updated as necessary

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Key Assumption: Case Temperature

• Savings vary based on temperature of the display case EC Motors are retrofitted in– Refrigeration interaction

• Existing workbook used actual installation data to understand distribution of installation between low temp (LT) and med temp (MT) case– This data is no longer collected

• Low – medium temperature ratio calculated using data in CBSA for walk-ins,– Data for reach ins, not available– 65% MT, 35% LT.– Distribution almost identical to existing workbook