Transcript HPWH UES Measure Initial Review 16 April 2014 Agenda • • • • • Provisional Measure Review Method Overview Prelim Findings Measure Development Approach Simulation Validation Please provide feedback and concerns throughout. This.

HPWH UES Measure Initial Review
16 April 2014
Agenda
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Provisional Measure Review
Method Overview
Prelim Findings
Measure Development Approach
Simulation Validation
Please provide feedback and concerns throughout.
This is a brainstorming session as much as a
presentation.
Current Provisional Measures
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HPWH Type:
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Unheated buffer locations
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Tier 1, 50-75 gallons
Tier 1, 75+ gallons
Tier 2
Includes garages and basements together
Heated installations
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One measure for each of gas furnace, electric furnace, zonal resistance, and heat pump heating
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Tier 1 water heaters have no exhaust ducting
Tier 2 water heaters all have exhaust ducting
The measures cross the entire PNW and are not separated by climate zone
Annual Energy Saving (kWh/yr)
HPWH Location
Unheated Buffer Location
Interior Location
Interior Location
Interior Location
Interior Location
Space Heat Type
Any Heat Type
Gas Heated Home
Zonal Electric Heated Home
Electric Furnace Heated Home
Heat Pump Heated Home
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
952
833
837
1,686
1,243
Method
Proven Unit Energy Savings
• Calibrated Engineering Approach
– Heat Pump Water Heater Model Validation and
Process Evaluation Project designed specifically to
move HPWH measure from provisional to proven
status.
• Even designed under the current guidelines (hooray!)
– Final energy savings will be calculated with a
simulation of HPWH behavior
• Inputs to simulation need to be solid
• Simulation needs to be validated
Simulation Inputs & Characteristics
• Simulation inputs come from the completed
field studies:
– Inlet water temperature, ambient air temperature,
tank set point, water draw pattern
– Investigated, categorized, and normalized where
necessary (e.g. by climate or number of
occupants)
• To extend to entire PNW, additional
characteristics will come from RBSA survey
– Ex: occupant count
Simulation Validation
• Validated against field measurements of
energy use
– Categorized by climate, equipment type,
installation location, draw patterns, etc.
Preliminary Findings
(subject to change. your mileage may vary. etc.)
• Findings used in two, broad ways:
– For simulation inputs
– To validate outputs
Findings are as expected:
• Energy use
GeoSpring>Voltex>ATI
• Resistance heat slope is
about 0.2 kWh/gal
Findings are as expected:
• Energy use
Garage>Basement>Interior
More Findings
• Inlet water
– by region / climate
• Ambient air temperature
– by install location
• Outlet water
– input from site visit records on setpoints
– measured outlet temperatures
• Will use inlet measurements to build inlet
water temperature profiles for use in
simulation as a function of geography
Creating Hot Water Draw Profiles
• Average daily use per person: 17.1 gallons
– Provisional measure used 18.2 gallons
• Will also investigate the following to inform our draw
patterns:
– Average number of draws per person per day
• at 1 gallon resolution
– Draw sizes
• Ex: # of 1 gal draws, # of 2 gal draws, # of 3 gal draws, etc….
Final UES Development Approach
• Categories and Prototypes
– Are calculated and modeled separately but then
combined with weighted averages to produce
ultimate savings estimates
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Climate Zone
Installation Location
Heating System Type
Prototypical Draw Patterns
– 1, 2, & 4 person draws
Key Assumptions
• RBSA population characteristics represent the houses
installing HPWHs
• Water draws are the same between ERWH and HPWH
– Both are storage tanks
– Metered energy data from DHP study and RBSA Metering study can
help confirm
• Space heating interaction
– Fractional or full?
• Current assumption for interior installations is full interaction: one unit of heat
removed from the air in the heating season is replaced by one unit of heat output
from the heating system
– Supplemental heat
• A negative heating interaction will show up as a change in supplemental heat
requirements. Those heat requirements, per the DHP analysis, will show up as a
cost in the non-energy benefits stream and not as a penalty to the electric grid.
Schedule
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All analysis currently underway
Report writing in April & May
Workbook development in May & June
Workbook refinement in June & July
Final report before RTF presentation
Full RTF presentation in July or August
Simulation Validation
• Graphs of metered and simulated data
• Work still underway to tune the simulation
Voltex 60: Measured & Modeled
Voltex 80: Measured & Modeled