UES Measure Update Proposal
Regional Technical Forum
November 18, 2014

2
• Measure Overview and Context
• Summary of Provisional Measure and Research
• Subcommittee Summary
• Measure Savings, Cost,
Life, TRC B/C
• Proposed Decision

3
Measure Developers
Contract Analyst Review
Ecotope, NEEA, BPA
Yes (Christian Douglass, Adam Hadley)
Technical Subcommittee Review Yes
Research & Evaluation
Subcommittee Review
Not yet

4
• 55% of 4 million households in PNW have electric water heaters (2011 RBSA SF Survey)
• 2.7 people in a house use 3,380 kWh/yr on site (2014
RBSA Metering Study)
• 3.38 MWh/yr x 2.2 million households / 8760 hrs/yr
= 850 aMW of site electricity
• HPWHs have roughly an annual COP of 2
• Site electric savings potential = 425 aMW

5
• Approved as Provisional UES on October 4, 2011 (Tier 2 ducted approved February 14, 2012)
• The measures cross the entire PNW and are not separated by climate zone
Annual Energy Saving (kWh/yr)
HPWH Location Space Heat Type
Unheated Buffer Location Any Heat Type
Interior Location Gas Heated
Interior Location Zonal Electric Heated
Interior Location Electric Furnace Heated
Interior Location Heat Pump Heated
Tier 1
Small
Tank
887
1,547
648
556
1,189
Tier 2
Large
Tank Any Size
1,817 1,794
2,169 1,724
957
833
952
837
1,686 1,243

6

7
• Field Studies
1.
“NEEA Heat Pump Water heater Field Study Report.” Fluid Market Strategies, for NEEA. October 22, 2013.
2. “Heat Pump Water Heater Model Validation Study” DRAFT REPORT. Ecotope, for NEEA. July 28, 2014.
• Lab Coefficient of Performance (COP) Tests
1.
Larson, B. and M. Logsdon. “Laboratory Assessment of Sanden GES-15QTA Heat Pump Water Heater.” Ecotope for
NEEA. Nov 6, 2013.
2. Larson, B., and Logsdon, M. February 2012. Laboratory Assessment of AO Smith Voltex Hybrid Heat Pump Water
Heater. Prepared for the Northwest Energy Efficiency Alliance. Retrieved from: https://conduitnw.org/_layouts/Conduit/FileHandler.ashx?RID=888
3. Larson, B., and Logsdon, M. February 22, 2012. Laboratory Assessment of AirGenerate ATI66 Hybrid Heat Pump
Water Heater. Prepared for the Northwest Energy Efficiency Alliance. Retrieved from: https://conduitnw.org/_layouts/Conduit/FileHandler.ashx?RID=887
4. Larson, B., and Logsdon, M. September 2012. Laboratory Assessment of General Electric GeoSpring Hybrid Heat
Pump Water Heater. Prepared for the Northwest Energy Efficiency Alliance. Retrieved from: https://conduitnw.org/_layouts/Conduit/FileHandler.ashx?RID=1183
5. Larson, B. March 2013. Laboratory Assessment of AirGenerate ATI80 Hybrid Heat Pump Water Heater. Prepared for the Northwest Energy Efficiency Alliance. Retrieved from: https://conduitnw.org/_layouts/Conduit/FileHandler.ashx?RID=1522
6. Larson, B. June 2013. Laboratory Assessment of Rheem HB50RH Heat Pump Water Heater. Prepared for the
Northwest Energy Efficiency Alliance. Retrieved from: https://conduitnw.org/_layouts/Conduit/FileHandler.ashx?RID=1646
7. Larson, B., and Logsdon, M. August 2014. Laboratory Assessment of AO Smith SHPT-50 Heat Pump Water Heater.
Retrieved from: https://conduitnw.org/Pages/File.aspx?RID=2179
• Space Heat Interaction Studies
1. Widder SH, JM Petersen, GB Parker, and MC Baechler. July 2014. Impact of Ducting on Heat Pump Water Heater
Space Conditioning Energy Use and Comfort. PNNL-23526, Pacific Northwest National Laboratory, Richland, WA.

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• http://rtf.nwcouncil.org/meetings/2012/02/HPWH_Ducted_Interior_Instal lations_Provisional_Proposal_021412_v5.pptx
Study Area Research Outcome Status
Hot Water
Consumption
In-field COP
100+ Households successfully metered. Draw profiles created for 1,
2, 3, 4, & 5+ occupancy households
• 100+ Households successfully metered.
• Inlet & outlet water temperature.
• Ambient air temperature.
• Water heater energy use.
Indeterminate Space Conditioning
Interaction (nonducted and exhaust ducted units)

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Summary of Research Outcomes, By Parameter
Parameter
Tank Setpoint
Inlet Water
Temperature
Hot Water
Consumption
Ambient Space
Temperatures
Heating System
Interaction
HPWH Efficiencies
Model Calibration
Existing
~122.5°F
Proposed
128°F
Assumed constant ~50°F Varies throughout the year and based on water source
45 gal/day with no draw schedule
40 gal/day average. Independent draw schedules for 1, 2, 3, 4, &
5+ person households
Estimates with “loosely” calibrated simulations
100%
Calculated based on model fits to observed data
65% (subcommittee judgment)
Based on lab tests
Uncalibrated
Based on lab Tests and calibrated to field data
Calibrated

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Subcommittee Summary: Dates & Attendees
October 21, 2014 (2 hours) November 6, 2014 (1.5+ hours)
Link to Presentation
Link to Meeting Notes
Attendees:
• Jennifer Anziano
• Christian Douglass
• Ben Larson
• Robert Weber
• Aaron Winer
• David Thompson
• Josh Rushton
• Andie Baker
• Rick Knori
• Brad Acker
Link to Presentation
Link to Meeting Notes
Attendees:
• Jennifer Anziano
• Christian Douglass
• Ben Larson
• Robert Webber
• Aaron Winer
• David Thompson
• Josh Rushton
• Andie Baker
• Mark Johnson
• Dave Kresta
• Sarah Widder
• Kevin Price
• Jeff Harris
• Kevin Watier
• Adam Hadley

11
Subcommittee Summary: Consensus on Specifics
• Model calibration (10/21)
– The HPWH model developed within SEEM is sufficiently calibrated for the purposes of estimating a UES.
• How to treat the impending federal water heater standard
(10/21)
– Assume the federal standard goes into effect now (instead of April
2015). The staff resources to develop multiple measure sets is not worth the effort and could be cumbersome for programs.
• Whether to have an "any size" tank measure or separate
small/large tank measures (10/21)
– An "any size" measure based on the weighting of small and large tanks in the region is appropriate. A relatively short sunset date (~1 year) should be used to monitor market shifts in average tank size.

12
Subcommittee Summary: Consensus on Specifics
(continued)
• Valuing self-install labor at zero cost (10/21)
– Defer this discussion to the broader RTF, since it relates to the Guidelines and many measures in addition to HPWH.
• HVAC interaction for interior installations (11/6)
– Provisionally assume a heating interaction factor of HC f ducted and non-ducted.
= 65% for exhaust
– Pursue a dual research plan using a.) the PNNL lab homes and b.) a “paper study” which looks at the correlation between temperature depression and
HC f
.
• Baseline for large tanks impacted by federal standard (11/11 - 11/14 over email)
– Collecting data on existing tank size is appropriate
– An additional or supplemental survey may be used to elicit baseline information
• Where to include houses with DHPs (11/11 - 11/14 over email)
– Bundle DHPs with Heat Pumps in the measure identifier

• Option 1: Additional study using PNNL lab homes (~$100k)
– Will help provide a better understanding of the range of interaction factors by testing four more HPWH locations throughout the lab home
• Option 2: “Paper study” (~$10k)
– Low cost option using existing data and models to help bound interaction factor
• Option 3: Large scale, “flip-flop” field research study (~$1M)
– The most comprehensive study, it would provide a direct output of the factor of interest
– Is such an expensive study worth it?
• Yes, because HPWH is a huge resource (~400 aMW) and our current uncertainty causes savings to vary by +/- 20%?
• Subcommittee recommends developing a research plan combining
Options 1 and 2
– Why? Options 1 and 2 are relatively low cost, yet they may bound the factor to an acceptable level
– If this turns out not to be the case, Option 3 is still on the table
13

14
• 57 measure applications
• Measures identified by tank location, HVAC type, efficiency, and exhaust ducting (yes/no) (note: tank size not a proposed identifier at this time)
HZ1
Location / HVAC Type Tier 1 Tier 2 Tier 2 Ducted
Interior Gas 1,231 1,309 1,218
Interior EFAF
Interior HP
Interior Zonal
Garage
Basement
892 911
1,089 1,134
930 956
1,016 1,220
1,116 1,223
N/A
N/A
798
1,047
786
HZ2
Location / HVAC Type Tier 1 Tier 2 Tier 2 Ducted
Interior Gas 1,297 1,376 1,281
Interior EFAF
Interior HP
Interior Zonal
Garage
Basement
982 1,006
1,114 1,156
1,018 1,049
847 1,252
1,155 1,267
N/A
N/A
842
1,045
806
HZ3
Location / HVAC Type
Interior Gas
Interior EFAF
Interior HP
Interior Zonal
Garage
Basement
Tier 1 Tier 2 Tier 2 Ducted
1,328 1,436
1,040 1,096
1,143 1,208
1,074 1,136
708 1,287
1,161 1,314
N/A
N/A
1,337
900
1,059
849

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2 500
Heating Zone 1
Existing, Large Tank Existing, Small Tank Proposed, Any Size Tank
2 000
1 500
1 000
500
0
Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any
Interior Gar. Base.
Interior Gar. Base.
Interior Gar. Base.
Tier 1 Tier 2 w/ Exhaust Ducting Tier 2 NO Ducting
Gar. = Garage, Base. = Basement

16
2 500
Heating Zone 2
Existing, Large Tank Existing, Small Tank Proposed, Any Size Tank
2 000
1 500
1 000
500
0
Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any
Interior Gar. Base.
Interior Gar. Base.
Interior Gar. Base.
Tier 1 Tier 2 w/ Exhaust Ducting Tier 2 NO Ducting
Gar. = Garage, Base. = Basement

17
2 500
Heating Zone 3
Existing, Large Tank Existing, Small Tank Proposed, Any Size Tank
2 000
1 500
1 000
500
0
Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any Gas EFAF HP Zonal Any Any
Interior
Tier 1
Gar. Base.
Interior Gar. Base.
Tier 2 w/ Exhaust Ducting
Interior Gar. Base.
Tier 2 NO Ducting
Gar. = Garage, Base. = Basement

18
• Measure life
– Existing: 15 yrs (Source: ??)
– Proposed: 13 yrs (2009 DOE TSD )
• Incremental Cost
$2 000
$1 800
$1 600
$1 400
$1 200
$1 000
$800
$600
$400
$200
$-
Tier 1 Tier 2 w/ Exhaust
Ducting
Tier 2 NO Ducting
Existing,
Large Tank
Existing,
Small Tank
Proposed,
Any Size Tank

19
Heating System
Any
Zonal Electric
Resistance
Electric Furnace
Heat Pump
Gas Furnace
Location
Garage
Basement
Interior
Ducted
Interior
Ducted
Interior
Ducted
Interior
Ducted
Tier
Tier1
Tier2
Tier1
Tier2
Tier1
Tier2
Tier2
Tier1
Tier2
Tier2
Tier1
Tier2
Tier2
Tier1
Tier2
Tier2
0.5
1.4
0.7
0.6
1.2
0.5
0.4
1.6
0.7
HZ1
1.6
0.7
1.8
0.7
1.3
0.5
0.4
Climate Zone
HZ2
1.3
0.8
1.8
0.8
1.4
0.6
0.4
0.5
1.6
0.7
0.6
1.4
0.6
0.4
1.6
0.7
0.5
1.6
0.8
0.6
1.4
0.6
0.4
1.6
0.7
HZ3
1.1
0.8
1.8
0.8
1.5
0.6
0.4

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“I ______ move the RTF:
• Update the savings, cost, and life for the HPWH UES measures as proposed and set the measure to Provisional category and Under Review status
• Direct staff to develop research plan focused on:
1.
HVAC interaction factor, using a combination of a PNNL lab homes study and a paper study, as proposed; and
2.
Determining baseline for large tanks (>55 gal), using data on existing tank size and possibly survey data.
• Set the sunset date to 4/2015, at which time the RTF will review the proposed research plan, and if approved, set the measure to Active status.”

21

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• Applies only to interior ducted or non-ducted installations (i.e. garage and unconditioned basement installs are excluded from this discussion)
• Heat pump water heaters extract heat from the space where they are installed. Some of that heat energy is replaced by the heating system.
• We have observed that not every unit of energy removed from the air by the HPWH is replaced by the heating system
Electric Storage Tank Water Heaters
Location
Basement
Overall
29% n
240
Main House
Garage
44%
19%
361
155
Crawl
Other
4%
3%
31
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Source: RBSA
Is the WH Space Location Conditioned?
Location No Yes
Basement
Main House
Garage
16%
5%
92%
84%
95%
8%
Crawl
Other
Overall
86%
75%
30%
14%
25%
70%

Cool HPWH
Exhaust Air
Warm
House Air
Tank Heat Losses
• HVAC System Interaction = m*c p
*ΔT + Q
UA
• Typical air Δ T at 68

F entering air: ~15

F
23

Cool HPWH
Exhaust Air
Warm
House Air
Added
Infiltration
Load
Tank Heat Losses
• HVAC System Interaction = m*c p
*ΔT + Q
UA
• Δ T now depends on outside air T
• m now depends on added infiltration load
24

25
• Field study of HPWH interaction factors was inconclusive
• What we know from PNNL Lab Homes Study 1
– Interaction factor for interior HPWH installations ≈ 49%
– Interaction factor for ducted HPWH installations ≈ 44%
– Study looked at one installation of a HPWH in a closet next to an exterior wall
1 PNNL. Impact of Ducting on Heat Pump Water Heater Space Conditioning Energy Use and
Comfort . July 2014.

26
PNNL. Impact of Ducting on Heat Pump Water Heater Space Conditioning Energy Use and Comfort . July 2014.

27
• Subcommittee agreed that HVAC factor would differ for heated basements versus more central, “main house” locations
• Assume HVAC factor of 50% for heated basements, 75% for main house
• Weight these by RBSA saturation for electric tank locations (basement - 36.8%, main house
– 63.2%)
• Weighted average ≈ 65%