Transcript Ben Larson 2 November 2010 [email protected] 4056 9th Avenue NE, Seattle, WA 98105 (206) 322-3753

Ben Larson
2 November 2010
[email protected]
4056 9th Avenue NE, Seattle, WA 98105
(206) 322-3753

Background:
 New Oregon residential energy code proposal
analysis. The OR-BCD has asked the RTF and
Ecotope to produce a savings estimate.

Last Meeting:
 Presented methodology

Goals Today:
 Present analysis findings & recommendations
 Obtain approval of predicted savings
2


Code revision goal is to reduce whole-house
energy use by 10% over the 2008 code.
Code covers single family detached and
multi-family dwellings 3 stories or less.
3

Determine representative characteristics of housing
population including:






Climates
Single Family (SF) and Multifamily (MF) occupancies
HVAC systems
Prototype buildings
Compile base case and proposed code requirements
Calculate annual energy use for the representative
housing population. End uses considered include:
 Heating, Cooling, Ventilation, Lighting, and DHW

Weight calculation outputs together based on housing
population data
4
Climate
Single
Family
Multi Family
Portland
0.59
0.19
Redmond
0.15
0.01
Medford
0.06
0.01
State Average
0.79
0.21
System Type
Single
Family
Multi-family
Gas Furnace
0.26
0.12
Gas Furnace with Cooling
0.56
0.2
Heat Pump
0.09
0.05
Electric Resistance Zonal
0.09
0.63
5

Single Family unchanged from 28 September:

1344ft2 – Single story over crawl space
 2688ft2 – Like 1344, but over a conditioned basement
 2200ft2 – 1.5 story split level with garage and bonus room (over crawl)

Updated: Multifamily prototype is a single unit in an eight
unit townhouse complex.

Prototype used in previous OR analysis (at least as early as 1990)
 952ft2 conditioned area per unit (stacked units, 4 on bottom, 4 on top)
 Both slab-on-grade and crawl space modeled

SF Prototype
Weight
MF Prototype
Weight
1344
0.15
952 crwl
0.78
2200
0.75
952 slab
0.22
2688
0.1
Net result: 51 different house types resulting from
combination of climates, prototypes, and heating systems.
6

Code proposal uses the existing core prescriptive
requirements from 2008
 (but does add provision for heat pump aux heat outdoor temperature lockout)

The new code savings come from a revised set of
additional measure tables. The code will require the
selection of two measures.
 The measures are divided into two categories with one
measure being selected from each category.
▪ Envelope Enhancement Measures (6 options)
▪ Conservation Measures (7 options)
7
EnvelopeEnhancement
Measures






1 High efficiency walls & windows:
Exterior walls – U-0.047 / R-19+R-5 (sheathing)
Windows-U-0.30
2 High efficiency envelope:
Exterior walls – U-0.058 / R-21
Flat ceilings – U-0.025 / R-49
Framed floors – U-0.025 / R-38
Windows – U-0.30
Doors- All U-0.20, or Add’l 15% high-efficacy lamps
3 High efficiency ceiling, windows & duct sealing:
Flat ceilings – U-0.025 / R-49, and
Windows-U-0.30, and
Performance tested duct systems
4 High efficiency thermal envelope UA:
Proposed UA is 15% lower than the Code UA
5 Building tightness testing, ventilation & duct
sealing:
A mechanical system providing ventilation rates
specified in Table 1101.1(3), or ASHRAE 62.2.
Blower door testing to 6.0 air changes per hour.
Performance tested duct systems.
6 Ducted HVAC systems within conditioned space
Conservation
Measures







A High efficiency HVAC system:
AFUE of 90% gas furnace
HSPF of 8.5 heat pump (SEER 13)
B Ducted HVAC systems within conditioned space
C Ductless heat pump:
DHP in primary zone with HSPF 8.5 (resistance heat
allowed in secondary zones).
PTHP with comparable efficiency ratings (no
supplemental zonal heaters installed in the building)
and integrated backup resistant heat is allowed in a
PTHP.
D High efficiency water heating & lighting:
Gas tankless EF of 0.80, and 75% CFLs
E Energy management device & duct sealing:
Performance tested duct systems , and 75% CFLs
F Solar photovoltaic:
Minimum 1 Watt / ft2 conditioned floor space
G Solar water heating:
Minimum of 40 ft2 of gross collector area
8


43 possible combinations of additional
measures (after excluded combinations
removed)
2394 independent simulation and calculation
runs
9


The savings for each measure is a weighted sum of all the
house types across the state
Analysis estimates of measure combinations:
 14 achieve 6-9% savings
 3 achieve 9-10% savings
 26 achieve 10-39%
▪ high savings due to certain DHP measure combinations
▪ without DHP, savings is 10-17%

Next slide shows the savings for each measure combination.
Solar measures left off the table but are included in the
overall analysis.
10
*Excludes Solar Measures
Statewide Savings
Envelope Measure
Conservation Measure*
7.1%
13.4%
18.2%
6.0%
6.4%
7.8%
14.3%
19.1%
7.0%
7.3%
6.7%
13.4%
19.3%
5.6%
6.1%
11.2%
11.5%
10.8%
9.9%
16.2%
39.5%
11.1%
9.5%
8.2%
8.4%
7.4%
14.7%
14.8%
8.1%
Walls & Windows
Walls & Windows
Walls & Windows
Walls & Windows
Walls & Windows
Envelope & Doors
Envelope & Doors
Envelope & Doors
Envelope & Doors
Envelope & Doors
Envelope & Lights
Envelope & Lights
Envelope & Lights
Envelope & Lights
Envelope & Lights
Ceiling, Window & Duct Sealing
Ceiling, Window & Duct Sealing
Ceiling, Window & Duct Sealing
UA 15% Reduction
UA 15% Reduction
UA 15% Reduction
UA 15% Reduction
UA 15% Reduction
Bldg Tightness & Duct Sealing
Bldg Tightness & Duct Sealing
Bldg Tightness & Duct Sealing
Ducts Inside
Ducts Inside
Ducts Inside
HVAC System Upgrade
Ducts Inside
DHP
75% CFLs & Demand-Gas Water Heater
75% CFLs & Duct Sealing
HVAC System Upgrade
Ducts Inside
DHP
75% CFLs & Demand-Gas Water Heater
75% CFLs & Duct Sealing
HVAC System Upgrade
Ducts Inside
DHP
75% CFLs & Demand-Gas Water Heater
75% CFLs & Duct Sealing
HVAC System Upgrade
Ducts Inside
75% CFLs & Demand-Gas Water Heater
HVAC System Upgrade
Ducts Inside
DHP
75% CFLs & Demand-Gas Water Heater
75% CFLs & Duct Sealing
HVAC System Upgrade
Ducts Inside
75% CFLs & Demand-Gas Water Heater
HVAC System Upgrade
75% CFLs & Demand-Gas Water Heater
75% CFLs & Duct Sealing
11

In practice, housing market will be built with an
uneven selection of these measure combinations
 Therefore, the overall savings will be a set of the measure
combinations.
▪ Selection likely to be driven by cost and minimum perturbation to
existing practices. Some emerging technologies, however, (DHPs,
tankless & heat pump water heaters) may alter market dynamics.

Due to (obvious) lack of data of future market
behavior, we conducted a sensitivity analysis
examining different possible scenarios of measure
combination selections
12
Equal – combinations selected with equal likelihood (not realistic)
 HVAC – furnace, ducted heat pump, and ductless heat
pumps upgrade options widely selected
 DHW – tankless gas water heater preferentially selected
 Middle– middle of the road scenario
 Low – lowest (worst case) likely savings scenario where
builders select options that save the least


All scenarios bounded by some constraints such as known
population of ducted houses, basements, etc.
13
Envelope Enhancemnt
Measures
Conservation
Measures
Scenario Equal
1 Walls & Windows
0.14
2d Envelope & Doors
0.14
2l Envelope & Lights
0.14
Ceiling, Window & Duct
3 Sealing
0.14
4 UA 15% Reduction
0.14
5 Bldg Tightness & Duct Sealing 0.14
6 Ducts Inside
0.14
A HVAC System Upgrade
0.14
B Ducts Inside
0.14
C DHP
0.14
75% CFLs & Demand-Gas
D DHW
0.14
E 75% CFLs & Duct Sealing
0.14
F Solar PV
0.14
G Solar Thermal
0.14
Savings 12.0%
HVAC DHW Middle Low
0.07 0.10 0.02 0.07
0.07 0.10 0.11 0.09
0.07 0.10 0.11 0.09
0.07
0.07
0.40
0.25
0.75
0.01
0.13
0.10
0.10
0.40
0.10
0.52
0.01
0.10
0.05 0.30
0.05 0.06
0.01 0.01
0.01 0.01
10.5% 9.5%
0.03
0.03
0.50
0.20
0.71
0.01
0.08
0.02
0.03
0.60
0.10
0.70
0.00
0.05
0.18 0.19
0.01 0.05
0.01 0.01
0.01 0.01
9.6% 8.8%
14

The explored scenarios deliver a savings
range from 8.8% to 10.5%. The middle
scenario shows savings of 9.6%
 A savings of at least 9.5% generally holds for
other scenarios and combinations (not shown
here)

Savings are still short of 10% target, but there
is another source…
15

Proposed code changes include provisions for improving house
addition and remodel energy performance.
 2008 version additions:
▪ <400ft2 core requirements only
▪ >400ft2 core requirements plus one additional measure (like new construction)
 Proposed changes for additions:
▪ <200ft2 core requirements only
▪ 200-600ft2 core requirements plus one additional measure
▪ >600ft2 core requirements plus two additional measures (like new construction)

Remodel changes not modeled but there are significant changes
▪
▪
▪
▪
▪
Windows:
Doors:
Flat ceilings:
Slab perimeter:
Underfloor:
U-0.65  U-0.35
R-2  R-5
R-38  R-49
R10  R-15
≥2x10 Joist R-21R-30, ≤2x8 Joist R-21R-25
16

Share of single family new construction based on floor area
 Data from Construction Monitor for Clackamas, Columbia, Marion,
Multnomah, Polk, Tillamook, Washington, and Yamhill Counties in
2009
Type
Percent
n
New Buildings
92%
3016
Additions > 600 ft2
5%
480
Additions 200-600ft2
3%
510
▪ Additional permit activity not counted in table: remodels (1516), additions with no
reported square footage (815), and change of occupancy (617).

There is an extensive set of possible combinations for
constructing a code-compliant addition. The savings
contribution will be small but likely not entirely insignificant.
17


An in-depth analysis not conducted because the population
is small and extremely challenging to characterize
A general analysis suggests an additional 0.2-0.5% savings is
possible from the most promising sources.
 Includes the window upgrade for remodels and the effect of additions
shown in the table below.
Area
Savings Type
Savings
estimate*
Add’l
measures
>200ft2
None
0%
0
200-400ft2
New
3-7%
1
400-600ft2
None
0%
1
>600ft2
New
6-15%
2
*Based on simplified test case simulations and calculations
18
New construction from code proposal is likely to see
a reduction in site energy use of 9-10% based on the
sensitivity analysis of probable measure selection.
 The proposals to improve performance of remodels
and additions is likely to provide extra savings
(~0.5%).
 Decision: The probability the Oregon residential
code proposal will realize the 10% target is ?

 A. Very probable
 B. Reasonably probable
 C. Highly improbable
19
20



Envelope Measures 1-3: Window from U-0.30
to U-0.28 or U-0.25
Furnace AFUE from 90 to 92
House Infiltration in Envelope Measure 5
from 6ach50 to 5ach50
21


Heating and Cooling with SEEM
Ventilation with SEEM and side calculations
 Building tightness measure requires mechanical ventilation


Lighting based on LPD and 1.5 hr/day on time
DHW use based on average SF and MF occupancy of 2.5 and
1.8 people per unit respectively
 Energy of hot water used is ~1150 kWh/yr/person (~22 gal/day)

MELs excluded from the analysis per OR BCD request
22






1 High efficiency walls & windows:
Exterior walls – U-0.047 / R-19+5 (insulation sheathing) / SIPS, and
Windows – Max 15% of conditioned area; or
Windows-U-0.30
2 High efficiency envelope:
Exterior walls – U-0.058 / R-21 Intermediate framing, and
Vaulted ceilings – U-0.033 / R-30, and Flat ceilings – U-0.025 / R-49, and
Framed floors – U-0.025 / R-38, and
Windows – U-0.30; and
Doors- All doors U-0.20, or
Additional 15 percent of permanently installed lighting fixtures as high-efficacy lamps
3 High efficiency ceiling, windows & duct sealing: (Cannot be used with Conservation Measure E)
Vaulted ceilings – U-0.033 / R-30, and Flat ceilings – U-0.025 / R-49, and
Windows-U-0.30 Windows- U-0.30, and
Performance tested duct systems
4 High efficiency thermal envelope UA:
Proposed UA is 15% lower than the Code UA when calculated in Table N1104.1(1)
5 Building tightness testing, ventilation & duct sealing:
A mechanical exhaust, supply, or combination system providing whole-building ventilation rates
specified in Table 1101.1(3), or ASHRAE 62.2, and
The dwelling shall be tested with a blower door and found to exhibit no more than:
1. 6.0 air changes per hour, or
2. 5.0 air changes per hour when used with Conservation Measure E, and
Performance tested duct systems
6 Ducted HVAC systems within conditioned space: (Cannot be used with Conservation Measure B or C) 23







A High efficiency HVAC system:
Gas-fired furnace or boiler with minimum AFUE of 90% a, or Air-source heat pump with minimum HSPF
of 8.5 or Closed-loop ground source heat pump with minimum COP of 3.0
B Ducted HVAC systems within conditioned space:
All ducts and air handler are contained within building envelope
C Ductless heat pump:
Replace electric resistance heating in at least the primary zone of dwelling with at least one ductless
mini-split heat pump having a minimum HSPF of 8.5. Unit shall not have integrated backup resistance
heat, and the unit (or units, if more than one is installed in the dwelling) shall be sized to have capacity to
meet the entire dwelling design heat loss rate at outdoor design temperature condition. Conventional
electric resistance heating may be provided for any secondary zones in the dwelling. A packaged
terminal heat pump (PTHP) with comparable efficiency ratings may be used when no supplemental
zonal heaters are installed in the building and integrated backup resistant heat is allowed in a PTHP.
D High efficiency water heating & lighting:
Natural gas/propane, on-demand water heating with min EF of 0.80, and
A minimum 75 percent of permanently installed lighting fixtures as CFL or linear fluorescent or a min
efficacy of 40 lumens per Watt as specified in Section N1107.2
E Energy management device & duct sealing:
Whole building energy management device that is capable of monitoring or controlling energy
consumption, and
Performance tested duct systems, and
A minimum 75 percent of permanently installed lighting fixtures as high-efficacy lamps
F Solar photovoltaic: Minimum 1 Watt / ft2 conditioned floor space
G Solar water heating: Minimum of 40 ft2 of gross collector area
24
Climate SF / MF
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
sf
PDX
mf
PDX
mf
PDX
mf
PDX
mf
PDX
mf
Proto
1344
1344
1344
1344
2200
2200
2200
2200
2688
2688
2688
2688
c952
c952
c952
c952
s952
HVAC Climate SF / MF Proto
HVAC
Final Weight
gfnc
0.777
0.75
0.15
0.26
0.023
gfac
0.777
0.75
0.15
0.56
0.050
hp__
0.777
0.75
0.15
0.09
0.008
zonl
0.777
0.75
0.15
0.09
0.007
gfnc
0.777
0.75
0.75
0.26
0.114
gfac
0.777
0.75
0.75
0.56
0.248
hp__
0.777
0.75
0.75
0.09
0.039
zonl
0.777
0.75
0.75
0.09
0.037
gfnc
0.777
0.75
0.1
0.26
0.015
gfac
0.777
0.75
0.1
0.56
0.033
hp__
0.777
0.75
0.1
0.09
0.005
zonl
0.777
0.75
0.1
0.09
0.005
gfnc
0.777
0.25
0.78
0.12
0.018
gfac
0.777
0.25
0.78
0.20
0.030
hp__
0.777
0.25
0.78
0.05
0.007
zonl
0.777
0.25
0.78
0.63
0.094
zonl
0.777
0.25
0.22
1.00
0.042
25
Climate SF / MF
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
sf
RDM
mf
RDM
mf
RDM
mf
RDM
mf
RDM
mf
Proto
1344
1344
1344
1344
2200
2200
2200
2200
2688
2688
2688
2688
c952
c952
c952
c952
s952
HVAC Climate SF / MF Proto
HVAC
Final Weight
gfnc
0.154
0.94
0.15 0.2607
0.006
gfac
0.154
0.94
0.15 0.5643
0.012
hp__
0.154
0.94
0.15 0.0897
0.002
zonl
0.154
0.94
0.15 0.0853
0.002
gfnc
0.154
0.94
0.75 0.2607
0.028
gfac
0.154
0.94
0.75 0.5643
0.062
hp__
0.154
0.94
0.75 0.0897
0.010
zonl
0.154
0.94
0.75 0.0853
0.009
gfnc
0.154
0.94
0.1 0.2607
0.004
gfac
0.154
0.94
0.1 0.5643
0.008
hp__
0.154
0.94
0.1 0.0897
0.001
zonl
0.154
0.94
0.1 0.0853
0.001
gfnc
0.154
0.06
0.78
0.12
0.001
gfac
0.154
0.06
0.78
0.2
0.001
hp__
0.154
0.06
0.78
0.05
0.000
zonl
0.154
0.06
0.78
0.63
0.004
zonl
0.154
0.06
0.22
1
0.002
26
Climate SF / MF
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
sf
MFR
mf
MFR
mf
MFR
mf
MFR
mf
MFR
mf
Proto
1344
1344
1344
1344
2200
2200
2200
2200
2688
2688
2688
2688
c952
c952
c952
c952
s952
HVAC Climate SF / MF Proto
HVAC
Final Weight
gfnc
0.068
0.93
0.15 0.2607
0.002
gfac
0.068
0.93
0.15 0.5643
0.005
hp__
0.068
0.93
0.15 0.0897
0.001
zonl
0.068
0.93
0.15 0.0853
0.001
gfnc
0.068
0.93
0.75 0.2607
0.012
gfac
0.068
0.93
0.75 0.5643
0.027
hp__
0.068
0.93
0.75 0.0897
0.004
zonl
0.068
0.93
0.75 0.0853
0.004
gfnc
0.068
0.93
0.1 0.2607
0.002
gfac
0.068
0.93
0.1 0.5643
0.004
hp__
0.068
0.93
0.1 0.0897
0.001
zonl
0.068
0.93
0.1 0.0853
0.001
gfnc
0.068
0.07
0.78
0.12
0.000
gfac
0.068
0.07
0.78
0.2
0.001
hp__
0.068
0.07
0.78
0.05
0.000
zonl
0.068
0.07
0.78
0.63
0.002
zonl
0.068
0.07
0.22
1
0.001
27