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Heat Pump Water Heater Model Validation, Market Progress Assessment, and Process Evaluation

RTF HPWH Sub-Committee MeetingOctober 15, 2012

Topics

• Quick Review of Study Goals

• Metering Site Selection

• Site Recruiting Process & Status

• Metering Protocols

• Process & Market Evaluation Updates

• Schedule Update

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Goal Review

• For active UES, need more information in 3 Primary Data Collection Areas:

• Hot water consumption

• In-field COP

• Space Conditioning Interaction

• Quick Review of Study Goals

• Metering Site Selection

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Metered Hot Water Consumption

• Metered DHW Energy Use Only (no flow):

• DHP Field Studies (all electric tanks) • NEEA: 95 sites• BPA: 50 sites

• RBSA Metering (gas and electric tanks):• 100 sites

• Total # Sites with Metered Energy Use: 245

• Metered DHW Energy and Hot Water Use:

• BPA/EPRI: 32 HPWH Sites + ~10 Traditional Tank Sites• NEEA/Fluid: 30 HPWH Sites• NEEA/RTF: 50 sites• Total # Sites; Metered Energy and Flow: 120

• National Studies:

• LBL Database

• Assume hot water use across all tank water heater types is similar

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Measurements: In-Field COP

• Data Collected

• Continuous monitoring; one minute intervals

• Hot water consumption (gallons)• HPWH energy consumption

• Compressor and electric resistance element run time extracted in data processing

• ΔT of water delivered• Ambient temperature• Inlet and Exhaust air temperature

• Two-Time Measurements

• For ducted units (assumes constant speed fan)• Airflow

• Sample

• 100+ Sites from 3 studies across the region

• Site selection determined by need to quantify independent performance variables

• Proposed selection in subsequent slides

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Measurements: Space Conditioning Interaction

• Interaction primarily determined through simulation using measurements as simulation constraints

• Data collected:

• Continuous monitoring; one minute intervals

• House heating energy use• Outside temperature• (Optionally, monthly billing data may produce a heating estimate)

• One-time measurements:

• House Audit, including• Unheated Buffer Space-to-House UA• Unheated Buffer Space estimate of internal gains (equipment audit)

• Sample

• 100+ Sites from 3 studies across the region

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HPWH Savings Estimate

• Build calibrated & validated models of HPWH performance

• Overlay simulation estimates on regional maps of natural (or potential) HPWH distribution

• Validating the model requires measurement of independent performance variables across:

• Heating climate zones,

• Installation locations, and

• Tank sizes

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Site Selection Drivers

• Quantify independent performance variables

• Environmental: Pre-determined by climate HPWH installation location. Primary drivers for our site selection categories.

• Ambient conditions of HPWH installation space• Cold water inlet temperature

• User: Secondary drivers for site selection – diverse user base & long metering period will likely provide needed variation

• Draw pattern, • Tank temperature setpoint, • Control strategy selection

• Equipment: Previously measured in lab so not a metering driver (but can also be confirmed in the field)

• Tank volume & heat loss rate• Heating component output capacity & efficiency• Control strategies

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Site Selection

• Memo from August 30, 2012Combined Current Studies Total Sites: 54

 

Tier 1 Tier 2Small Size < 55 gallons Large Size > 55 gallons Any SizeHZ1 HZ2 HZ3 HZ1 HZ2 HZ3 HZ1 HZ2 HZ3

Garage 14 0 0 3 0 0 8 4 0Unheated Basement 2 1 0 0 0 0 3 0 0Interior 2 0 2 0 0 0 -- -- --Interior Ducted -- -- -- -- -- -- 9 6 0

Planned New Installs Total Sites: 50

 

Tier 1 Tier 2Small Size < 55 gallons Large Size > 55 gallons Any SizeHZ1 HZ2 HZ3 HZ1 HZ2 HZ3 HZ1 HZ2 HZ3

Garage   2 1 5 0.5 0.5 0 0.5 0.5Unheated Basement 3 2 1 3 0.5 0.5 0 1 1Interior 4 2 0 4 2 0 -- -- --Interior Ducted -- -- -- -- -- -- 4 6 6

Final Disposition  Total Sites: 104

 

Tier 1 Tier 2Small Size < 55 gallons Large Size > 55 gallons Any SizeHZ1 HZ2 HZ3 HZ1 HZ2 HZ3 HZ1 HZ2 HZ3

Garage 14 2 1 8 0.5 0.5 8 4.5 0.5Unheated Basement 5 3 1 3 0.5 0.5 3 1 1Interior 6 2 2 4 2 0 -- -- --

Interior Ducted -- -- -- -- -- -- 13 12 99

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Site Recruiting: Process & Status

• Status

• Calling began last week• Some pre-qualification visits already scheduled

Sorted / Screened Call List

Recruiter Calls to Determine Eligibility

Recruiter Schedules Pre-Qualification Inspection Visit

Field Tech Conducts Qualification

Inspection Visit

Ecotope & Field Tech Determine

Final Qualification

Recruiter notifies site of ineligibility

Recruiter Schedules HPWH & Meter

Installation Visit

yes

no

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Metering Protocols

• Draft Protocol Memo from October 3, 2012

• Refer to Memo

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Test Metering Site Successful

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Process & Market Evaluation Updates

• Interview and Survey Guide Development

• Currently developing in-depth interview guides for:

• NEEA & Fluid Staff• Manufacturers, Distributors, Retailers• Installers (e.g., plumbers, contractors)• Partner Utility Staff

• Currently developing CATI survey guides for 100 homes:

• Homeowners with HPWHs installed through the market• Homeowners with HPWHs installed through our validation work• Survey disposition will be driven by market success

• Priority is surveying households who installed HPWHs through the market

• All interviews and surveys will occur in 2013, other than for NEEA staff

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Schedule Update

• Field Work

• Site recruiting October-November 2012

• Metering installs November-December 2012

• Metering period through June 30, 2012

• Process & Market

• NEEA staff interviews early November, 2012

• All other interviews and surveys in January-February, 2013

Questions?

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