Transcript Air Source Heat Pumps Potential Changes in the RTF’s Specifications & Savings Estimates and Their Impact on C&R Discount Program Credits.

Air Source Heat Pumps
Potential Changes in the RTF’s
Specifications & Savings Estimates
and Their Impact on C&R Discount
Program Credits
1
Why “Things” Are Changing – New
Energy Star Specifications
• Energy Star labeled air source heat pumps established
new performance criteria effective October 1, 2002
– Split System Minimums
• SEER – 13.0
• HSPF - 8.0
• EER – 11.0
– Package System Minimums
• SEER – 12.0
• HSPF – 7.6
• EER – 10.5
2
Why “Things” Are Changing –
PNW Climates Are Different
• ARI performance ratings (SEER & HSPF) are
based on climates that do not match the
Northwest’s.
– The “West Side” climates are warmer than the rating
location – HSPF is higher than label
– The “East Side” climates are colder than the rating
location – HSPF is lower than label
– All of the NW has lower humidity than the rating
location – SEER is lower than label
3
Climate Adjusted HSPF
The Impact of Climate on HSPF
9
8
7
6
5
4
3
2
1
0
Portland
Seattle
Rated HSPF = 7.1
4
Boise
Spokane
Rated HSPF = 8.0
Missoula
Climate Adjusted HSPF
Percent of ARI Rating
100%
80%
104%
105%
92%
91%
89%
Seattle
Boise
Spokane
Missoula
60%
40%
20%
0%
Portland
5
Why Things Are Changing –
Control Practices Reduce Performance
• Set-Back Thermostats (with or without “ramp up”
features) often result in use of electric resistance heat
• Timed-defrost controls (particularly on the “East Side”)
operate even when relative humidity is too low to
produce icing
• Compressor “cut-out” temperatures are set too high, so
compressor doesn’t operate even when it has a COP
above 1.0.
6
The Impact of Controls on HSPF
Control Adjusted HSPF
8
7
6
5
4
3
2
1
0
Portland
Seattle
Rated HSPF = 7.1
7
Boise
Spokane
Rated HSPF = 8.0
Missoula
Control Adjusted HSPF
Percent of ARI Rating
100%
80%
97%
94%
60%
68%
65%
62%
40%
20%
0%
Portland
8
Seattle
Boise
Spokane
Missoula
Why Things Are Changing Failure to Properly Commission Heat Pumps
• Field studies of heat pump and air conditioner
installations reveal
– Over/Under Charging of Refrigerant
– Low air flow across evaporator coils
9
Impact of Improper Commissioning
on HSPF
Commissioning Adjusted
HSPF
8
7
6
5
4
3
2
1
0
Portland
Seattle
Rated HSPF = 7.1
10
Boise
Spokane
Rated HSPF = 8.0
Missoula
Commissioning Adjusted HSPF
Percent of Rated HSPF
100%
80%
94%
94%
82%
82%
79%
Boise
Spokane
Missoula
60%
40%
20%
0%
Portland
11
Seattle
Cumulative Adjusted HSPF
Cumulative Impact on HSPF
7
6
5
4
3
2
1
0
Portland
Seattle
Rated HSPF = 7.1
12
Boise
Spokane
Rated HSPF = 8.0
Missoula
Cumulative Adjusted HSPF
Percent of Rated HSPF
100%
80%
85%
88%
60%
60%
59%
56%
Boise
Spokane
Missoula
40%
20%
0%
Portland
13
Seattle
SEER Doesn’t Match Label Either
• High performance air conditioning equipment is
designed to “de-humidify” by recovering latent
energy (heat of condensation)
• Preliminary research appears to show that SEER
ratings, when adjusted for the PNW “drysummer” climate are about 65% of nameplate
– Nominal 10 SEER => Real 6.5 SEER
14
Implications for C&R Discount
Values
• Difference Between “PTCS” Heat Pump (or
CAC) Installations & Non-“PTCS” Installations
Increases
• Difference between Non-PTCS Heat Pump (or
CAC) Installations and “Baseline” Installations
Decreases
15
Example 1 – Pre80 Single Family w/Furnace in
Heating & Cooling Zone 1
Case
Current w/o PTCS
Annual
Savings (kWh)
6,839
C&R Discount
Credit ($)
$ 2,241
Current w/PTCS
8,055
$
2,661
Proposed w/o PTCS
4,298
$
1,407
Proposed w/PTCS
6,484
$
2,155
Example 2 – Post79/Pre93 Single Family
w/Furnace in Heating Zone 1 & Cooling Zone 2
Case
Current w/o PTCS
Annual
Savings (kWh)
8,971
Current w/PTCS
C&R Discount
Credit ($)
$
3,036
10,308
$
3,496
Proposed w/o PTCS
7,386
$
2,514
Proposed w/PTCS
10,733
$
3,673
Example 3 – Post92 Single Family w/Zonal Heat
& No CAC in Heating Zone 1 & Cooling Zone 3
Case
Current w/o PTCS
Annual
Savings (kWh)
2,944
C&R Discount
Credit ($)
$
744
Current w/PTCS
4,045
$
1,153
Proposed w/o PTCS
631
$
(136)
Proposed w/PTCS
2,906
$
699
Example 4 – Pre80 Single Family w/Furnace &
w/o CAC in Heating & Cooling Zone 2
Case
Current w/o PTCS
Annual
Savings (kWh)
9,633
C&R Discount
Credit ($)
$ 3,119
Current w/PTCS
11,178
$
3,651
Proposed w/o PTCS
5,073
$
1,601
Proposed w/PTCS
8,425
$
2,739