Out-Of-Compliance Grocery UES Measure Recommendations
Regional Technical ForumJuly 15, 2014
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Presentation Outline• Background• Measure Overview• Staff Highlighted Areas• UES Workbook
– Measure Descriptions– Measure Analysis and Input Details– Savings, Cost, and Cost Effectiveness
• RTF Staff Recommendation• Proposed Decision
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Background• Multiple Grocery measures found Out-of-Compliance
– Subsequent analysis determined remaining potential small– Extended sunset date at November 2013 meeting– Staff to develop plan to bring back into compliance
• Grocery measures in question:1. ECMs for Walk-ins – Done2. Walk-in Evaporator Fan ECMotor Controllers – Done3. Compressor Head Fan Motor Retrofit to ECM – Done 4. Display Case LEDs (Open Cases) - Done5. Floating Head Pressure Controls for Single Compressor Systems - Done6. Door Gasket Replacement - Done7. Auto Door Closers8. Strip Curtains
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Background – Remaining PotentialRegional Priority Sector Measure
Remaining Potential
aMW (Cadmus)
Remaining Potential aMW for
next 2 years (PECI)
Notes
1 Grocery Grocery - Display Case LEDs (Open Cases)
0.48 N/A Measure of interest for PECI
2 Grocery Grocery - Floating Head Pressure Controls for Single Compressor Systems
0.46 0.06 Remaining potential is small for PECI program (when measure is limited to grocery sector)
3 Grocery Grocery - Autoclosers 0.26 0.21 Remaining potential is small for PECI program
3 Grocery Grocery - Door Gasket Replacement 0.65 0.021 Remaining potential is small for PECI program
3 Grocery Grocery - Strip Curtains 1.61 0.015 Remaining potential is small for PECI program
Note: Remaining potential based on PNW territory only.
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What hasn’t been done
• Estimating measure interactions very limited– Only looked at HVAC interaction within measure– Possible to have interactions among measures
RTF Measure Interactions
Auto Door Closers
Display Case LEDs (Open Cases)
Door Gasket Replacement
Floating Head Pressure Controls for Single Compressor Systems
Strip Curtains
Auto Door Closers x x
Display Case LEDs (Open Cases)
Door Gasket Replacement x x
Floating Head Pressure Controls for Single Compressor Systems
Strip Curtains x x
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RTF direction to take
• Last time RTF agreed with staff recommendation to ignore interactions for these small saver grocery measures– Staff estimate is that interactions are likely small
and do not warrant further research– Furthermore, estimation methods of measures are
varied and it may not be practical to reliably determine interactions
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Door Auto Closer on walk-ins and reach-ins
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Measure Overview
• What does it do?– Installs a new Door Auto Closer on existing walk-in
or reach-in case that either has one that is broken or does not have one at all
– Savings occur from:• Runtime reduction on refrigeration system• Load reduction on store HVAC heating system
– Assuming grocery stores heat most of the year
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Recommendation Memo ItemsRecommendation Memo Item Staff Response
The amount of time that doors are normally unintentionally left ajar, the Doorway Open Time Factor, is set at 25% of daily hours for all four measures. This assumption needs to be based on measured data.
Staff has no basis for estimating the Doorway Open Time Factor. Staff has assumed 25% for the purposes of this analysis, but note that this value could reasonably be between 0% and 100%. Savings are directly proportional to this value. Door open time is based on ADM study and PECI measured data from gasket test as a baseline.
The savings figure for the reach-in glass doors medium temperature measure is estimated assuming a 66% factor of the reach-in glass door low temperature measure figures. Support with data.
Small saver negates need to collect primary data. Professional Judgment will be used.
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Staff Highlighted Areas• Unintentional door open time
– Based on professional judgment only– Savings vary by orders of magnitude within the
range of reasonable assumptions
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Unintentional Door Open Time
• Value is meant to represent time door is left unintentionally open (i.e. almost closed)– Not the same as door open/close times for
accessing product• Gasket study open times as a reality test
Weighted average of all sites Mean
Minutes open per day
Autocloser reduction in
unintentional time left open
Minutes unintentionally
left open per day
Hours unintentionally
left open per day
Low-temp Reach-in Avg. 5.0% 71 25.0% 18 0.3Med-temp Reach-in Avg. 3.6% 52 25.0% 13 0.2Low-temp Walk-in Avg. 4.5% 64 25.0% 16 0.3Med-temp Walk-in Avg. 24.3% 350 25.0% 87 1.5
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Unintentional Door Open Time• But savings are directly proportional to this
estimate, with no data to support it
Reach-in Low Temp (LT) Reach-in Med. Temp (MT)0
200
400
600
800
1000
1200
Reach-in Autocloser Savings
10% 25% 50% 75%
Savi
ngs (
kWh/
yr)
Walk-in Low Temp (LT) Walk-in Med. Temp (MT)0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Walk-in Autocloser Savings
10% 25% 50% 75%
Savi
ngs (
kWh/
yr)
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Savings, Cost, & Cost Effectiveness
• Go to the following sections in the Presentation tab in the proposed measure workbook:– Measure savings– Measure costs– Measure TRC B/C ratios
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RTF Staff Recommendation• Deactivate measure due to high uncertainty in
Doorway Open Time Factor and resulting high uncertainty in savings.
• Set the measure status to “Deactivated”
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Proposed Decision
“I _______________ move that the RTF set the measure status of the ‘Door Auto Closer’ measure to ‘Deactivated.’”
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Strip Curtains on Walk-ins
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Measure Overview
• What does it do?– Installs a strip curtain on a walk-in freezer or
cooler where none existed before (so my picture was a little misleading)
– Savings occur from:• Load reduction of refrigeration system• Load reduction on store HVAC heating system
– Assuming grocery stores heat most of the year
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Recommendation Memo ItemsRecommendation Memo Item Staff Response
The measure definition should clarify whether or not the measure applies to walk-in units with loading dock exterior doors. The average environmental temperatures used in the ADM HIM report apparently include some fraction of exterior spaces.
The HVAC interaction factor has a small impact on savings. However infiltration air is large. Professional judgment needed.
Research Plan called for the collection of Time Door Open per Day for both pre- and post-installation periods to ensure the savings calculations account for any post installation variation in door open times. Results were presented from metering in August 2011, which showed that the results were not statistically significant. New data is needed.
Should we use non-statistically significant data for this parameter? Professional judgment needed. However, savings only range by a factor of 2 over a very wide range of assumptions.
The values for the Temperature of Surroundings parameter, which are found on the “Assumptions” worksheets for the various building types, need to be based on regional measured data.
If limited to walk-ins that no exterior doors, likely that surrounding temperatures are similar in CA grocery stores compared to the PNW.
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Staff Highlighted Areas• Temperature of Surroundings Parameter
– Some walk-ins open to unconditioned spaces– No adjustment for PNW compared to CA
• Strip Curtain Takeback– Do door open times increase after strip curtains are
installed?– Results are only moderately sensitive to this effect.
• Strip Curtain EUL– CA program evaluation found that measure was
typically replaced well before commonly assumed lifetime.
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Temperature of Surroundings• Used to determine infiltration air temp• A small swing of infiltration temp produces a large swing in savings
– Savings increase as infiltration temp increases• ADM study results use storage area temps in respective
establishments– These include some indoor and unconditioned zones
• No easy way to access ADM data on climate zone weightings to discern % of outdoor/indoor walk-ins used
• Recommend limiting measure eligibility to walk-ins that open to conditioned spaces only– Likely that storage areas/grocery stores same in PNW and CA– Walk-ins that open to outdoor spaces have higher infiltration air temps;
savings potential may be much larger
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Strip Curtain Takeback
• Door open time is a primary determinant• Some data on pre-install door open time• No statistical data on the ratio of post- to pre-
install door open times• Some anecdotal evidence does suggest significant
takeback can occur (i.e. post/pre ratio > 1)• Results only vary by a factor of 2 across a wide
range of assumptions (from post/pre ratio of 0.25 to 3).
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Example of Pre- and Post- Door Open Times
PECI Data- Cooler (n=10)
PECI Data- Freezer (n=3)
CPUC Data- Cooler (n=14)
CPUC Data- Freezer (n=9)
BPA Data- Cooler (n=10)
BPA Data- Freezer (n=4)
0
50
100
150
200
250
300
350
400
Pre
Post
Door
Ope
n Ti
me
(Min
/Day
)
August 2011 RTF presentation
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Example of Pre- and Post- Door Open Times
December 2007 BPA M&V presentation
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Strip Curtain Takeback• Effect of varying post-install times on savings.
- 200 400 600 800
Annual Savings by Post-Case Open Time Scenario
25% of pre-case open time 100% of pre-case open time200% of pre-case open time 300% of pre-case open time
Savi
ngs
(kW
h/yr
/sqf
t)
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Strip Curtain Takeback
• Recommend incorporating some level of takeback in estimate to – reflect anecdotal evidence – place savings in the middle of the range of
reasonable estimates• Staff using a ratio of 2:1 for post-pre door open times
• No significant data on this estimate• Up to RTF professional judgment
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Strip Curtain Lifetime• Typical EUL is four years.• However, CA impact evaluation found that
program-installed strip curtains were typically maintained more frequently.
Source: Commercial Facilities Contract Group 2006-2008 Direct Impact Evaluation Study ID: PUC0016.03 Volume 3 of 3 HIM Appendices
These findings suggest a mean time to replacement of 2 to 3 years.
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Savings, Cost, & Cost Effectiveness
• Go to the following sections in the Presentation tab in the proposed measure workbook:– Measure savings– Measure costs– Measure TRC B/C ratios
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RTF Staff Recommendation• Limit eligibility of measure to walk-ins that
open to conditioned spaces only• Assume a level of takeback that results in
savings in the middle of the range of possible savings. – Staff recommends a post/pre door open time ratio
of 2.• Set measure life to 2.5 years.
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Proposed Decision
“I _______________ move that the RTF:
• Approve the ‘Strip Curtain’ measure as a “Small Saver” UES;– Limited to walk-ins that open to conditions spaces only
– Using a post-install to pre-install door open time ratio of 2.0
– Using a measure life of 2.5 years
• Set the measure status to ‘Active;’ and• Set the sunset date to July, 2019.”
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