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TRANSCRIPT
BASELINE CHARACTERISTICS
OF THE 2002-2004 NONRESIDENTIAL SECTOR:
SEATTLE CITY LIGHT
For the
Northwest Energy Efficiency Alliance
David Baylon
Final Report October 31, 2008
Ecotope, Inc. i
Table of Contents
1. Introduction ................................................................................................................. 1
2. Sample Design .............................................................................................................. 1
3. Building Characteristics ............................................................................................. 2
3.1. Lighting ....................................................................................................................................... 2 3.2. HVAC ......................................................................................................................................... 5 3.3. Building Envelope .................................................................................................................... 10
3.4. Building Commissioning .......................................................................................................... 13 3.5. Operations / Training ................................................................................................................ 14 3.6. LEED
® Buildings ...................................................................................................................... 15
4. Energy Use and Energy-Use Intensities (EUIs) ...................................................... 15
5. Interviews with Architects and Designers .............................................................. 18
5.1. Interview Sample ...................................................................................................................... 19
5.2. Energy Codes ............................................................................................................................ 19
5.3. Attitudes Toward Energy Efficiency ........................................................................................ 20
6. Overall Observations ................................................................................................ 22
7. References .................................................................................................................. 24
Ecotope, Inc. ii
Table of Tables
Table 2.1: Sample Population by Building Type (N) ................................................................................. 2 Table 3.1: Distribution of Lamp Type (% of Total Lighting Watts) .......................................................... 3 Table 3.2: Distribution of Lighting Controls (% of Floor Area Controlled by Particular Strategy) .......... 3 Table 3.3: LPD by Building Type (Watts/sq. ft.) ....................................................................................... 4
Table 3.4: Actual LPD Code Requirements (Watts/sq. ft.) ........................................................................ 5 Table 3.5: Lighting Code Compliance Results ........................................................................................... 5 Table 3.6: HVAC Systems by Building Type (% Floor Area) ................................................................... 6 Table 3.7: Heat Source Type by Building Type (% Floor Area) ................................................................ 7 Table 3.8: Cooling Source Type (% Floor Area) ........................................................................................ 8
Table 3.9: Average Cooling Equipment Efficiency and Code Compliance (SCL Sample) ....................... 9 Table 3.10: Average Heating Efficiency and Code Compliance (SCL Sample) ...................................... 10 Table 3.11: Building Heat Loss Rate (UA/sq. ft.) .................................................................................... 10
Table 3.12: Window Area by Building Type (% of Gross Wall) ............................................................. 11 Table 3.13: Window U-Factor by Building Type (% of Glazing Area) ................................................... 12 Table 3.14: Window SHGC Category (% of Window Area) ................................................................... 12
Table 3.15: Envelope Code Compliance by Code (% and N) .................................................................. 13 Table 3.16: Reported Commissioning by Building Type ......................................................................... 14 Table 3.17: Operator Training as Reported by Building Operators (% of Buildings) .............................. 14
Table 3.18: LEED Certified Buildings Observed (N) .............................................................................. 15 Table 4.1: Total EUI summary (kBtu/sq. ft.) ............................................................................................ 16
Table 4.2: Total EUI summary (kWh/sq. ft.) ............................................................................................ 16 Table 4.3: Electric Only EUI summary (kWh/sq. ft.) ............................................................................... 17 Table 4.4: Adjusted EUIs from CBSA Regional Study (1990-2000 Cohorts) and CBECS..................... 17
Table 5.1: Interview Sample Distribution by Design Role ....................................................................... 19 Table 5.2: Reactions to Energy Code Provisions...................................................................................... 19
Table 5.3: Plan Reviewer or Building Official Feedback (%) ................................................................. 20 Table 5.4: Percent of Respondents Claiming “Beyond Code” in their Designs ....................................... 20
Table 5.5: Importance of Energy Efficiency to the Design Team (%) ..................................................... 20 Table 5.6: LEED
® Requested by Clients .................................................................................................. 21
Table 5.7: Opportunities to Promote Energy Efficiency .......................................................................... 21
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1. Introduction This summary presents the 2002-2004 baseline characteristics of nonresidential buildings within
the service territory of Seattle City Light (SCL). The summary is a breakout of utility specific
data collected as part of a larger regional study, Baseline Characteristics of the 2002-2004
Nonresidential Sector: Idaho, Montana, Oregon, and Washington (Baylon and Kennedy 2008).
The main research activities for the regional study included field visits and interviews with
design professionals and building operators. Please refer to the full report for a description of the
regional sample and characteristics of nonresidential buildings by state and building type.
Additionally, not all of the characteristics summarized in the full report are summarized here.
This is due to the insignificant number of cases available to generate certain comparisons (such
as building components compared by building type).
The Seattle City Light summary presents the following information:
Building Characteristics. General characteristics and specific characteristics associated
with the major energy-using components (lighting, HVAC, and envelope) of commercial
buildings. This information includes identification of building components, equipment,
and controls used in each building.
Energy Code Compliance. Energy code compliance is assessed for lighting, HVAC, and
envelope components.
Energy Use and Energy Use Intensities (EUIs). EUIs are presented by building type
within the SCL sample.
Interviews with Architects and Designers. Insights into the attitudes among design
professionals active in the commercial sector toward energy conservation, sustainable
design, and related practices.
2. Sample Design As part of the regional study a stratified random sample was designed to be representative of new
commercial construction in Idaho, Montana, Oregon, and Washington. The study included
development of a sample frame drawn from the F.W. Dodge® database. For a detailed
description of the techniques and design of the regional sample please see Section 3 of the
2002-2004 Baseline Study.
Individual utilities requested enhancements to the regional sample to allow their particular
service territories to be characterized independently. These samples were designed with the
same stratification boundaries used to develop the state samples. This allowed the maximum
overlap between the enhanced samples and the state samples, and thereby allowed the maximum
coverage for the particular utility service territories.
Seattle City Light requested additional buildings to ensure a statistically representative sample
for its service territory and allow more robust comparisons between its population and others in
the study. In addition, a few buildings were added within Seattle City Light’s sample to allow a
partial characterization of buildings certified by the U.S. Green Building Council’s (USGBC)
Leadership in Energy and Environmental Design (LEED®
) program. There were several
2
buildings in the original sample that were LEED certified. The utility asked for three buildings
to be added to complete a contemporary picture of this program in the Seattle area. Ultimately,
six LEED buildings were included in the sample. Two of these buildings were drawn from the
utility records and had no representation in the sample frame used for the rest of the study. For
this purpose the buildings added were not included in the characteristics summaries unless they
could be weighted from the original sample frame. They are included in a separate summary
focused on LEED certified buildings (Baylon, 2008).
Table 2.1 shows the final sample drawn for Seattle City Light, including both the overlap with
the state samples and the utility enhanced sample. This table does not include sample points that
were only part of the building type sample.
Table 2.1: Sample Population by Building Type (N)
Building Type SCL Washington Regional
Assembly 2 4 8
College 1 2 9
Schools 7 30 67
Grocery 0 10 18
Health Services 2 6 16
Hospital 4 13 25
Institution 3 10 23
Office 1 8 27
Other 0 2 9
Residential/Lodging 4 11 18
Restaurant / Bar 0 1 8
Retail 7 32 78
Warehouse 1 17 40
Total 32 146 346
3. Building Characteristics This section summarizes characteristics associated with the major energy using components
(lighting, HVAC, and envelope,) of commercial buildings in the Seattle City Light service
territory. This information includes identification of building components, equipment, and
controls used in each building. This section also outlines information collected on building
commissioning, operations/training, and LEED status.
The regional study also reviewed refrigeration systems; however, due to the insignificant number
of refrigeration system within each utility sample, these systems are not summarized in the
supplemental utility reports.
3.1. Lighting
Individual fixtures, lamps, and control strategies and technologies were determined using a
combination of plan review and field audit. The tables in this section present Seattle City
Light results for lighting technologies, lighting controls, and lighting power densities (LPD).
3
Lamps were divided into five classes: compact fluorescent (CFL), linear fluorescent (LF),
high intensity discharge (HID), incandescent (INC), and other.
Table 3.1 shows the distribution of lighting wattage by these classes. In cases where
particular samples have a large amount of residential type uses (e.g., motels, assisted living)
the fraction of incandescent lighting increases.
Table 3.1: Distribution of Lamp Type (% of Total Lighting Watts)
Building Type CFL LF HID INC Other Total
Assembly 24 53 10 13 0 100
College 40 7 0 53 0 100
Schools 9 64 26 2 0 100
Grocery — — — — — —
Health Services 14 71 0 16 0 100
Hospital 11 73 2 12 2 100
Institution 19 67 6 6 1 100
Office 10 77 0 13 0 100
Other — — — — — —
Residential / Lodging 26 24 0 25 25 100
Restaurant / Bar — — — — — —
Retail 5 65 20 10 0 100
Warehouse 0 13 81 6 0 100
Weighted Average (SCL) 15 56 14 11 4 100
Region 9 58 17 14 1 100
Table 3.2 presents the distribution of lighting controls. Lighting control has been
summarized into the following major categories observed throughout the sample:
Sweep control enables the building lighting to be shut off during unoccupied hours.
Lighting EMS integrates the lighting control into a central system with the HVAC
and other building systems.
Daylighting control provides an automatic system for turning off portions of a
building lighting system with the availability of daylight from windows or skylights.
Occupancy sensors monitor room or area occupancy and turn off lights when the
room in unoccupied.
Multi-level switching allows occupants to reduce lighting levels manually as lighting
needs change.
Table 3.2: Distribution of Lighting Controls (% of Floor Area Controlled by Particular Strategy)
Control Type SCL Washington Region
Sweep 42 39 37
Lighting EMS 58 41 34
Daylighting 61 25 18
Occupancy 70 46 47
Multi-Level Switching 41 34 39
4
Lighting power densities are summarized in Table 3.3. This summary includes all lights
in the building, both interior and exterior. Lighting that is exempted from the energy
code (e.g., security lighting, dental and medical lighting) has been included in this
summary if it is permanently installed in the building (not included with furnishings etc.).
It should be noted that these summaries are the relevant summaries for the buildings
surveyed. All buildings have some variation in LPD given the particular mix of
exemptions, and exterior lighting that were selected by the designer and builder. The
code regulates most of these exemptions separately outside the LPD allowances. Thus,
the comparison tables do not really reflect the relative severity of these requirements only
the mix of responses and requirements that the particular buildings in the sample
experienced.
Table 3.3 also includes a summary of the results of the 2000 building stock assessment
done for Seattle City Light. The nature of the 2000 sample is that it included much more
specialty retail than this study. While there have been improvements in the LPDs of the
retail sector (especially display lighting) the apparent change in this table is the result of
the major differences between these two samples. The baseline “office” sample is more
limited in large part because the construction of large offices was more limited in the
2002-2004 time period. The few buildings built included only LEED projects, which
probably reduced the LPD substantially. Aside from these sectors, the LPDs observed in
this sample are comparable to the previous sample.
Table 3.3: LPD by Building Type (Watts/sq. ft.)
Building Type SCL SCL 2000 Washington Region
Assembly 1.11 — 1.04 1.05
College 0.98 1.11 1.01 1.03
Schools 1.14 1.18 1.12 1.10
Grocery — 1.59 1.57
Health Services 1.47 1.35 1.33 1.36
Hospital 1.26 — 1.17 1.26
Institution 0.99 — 0.95 1.10
Office 0.74 .99 1.02 1.03
Other — .86 0.81 0.85
Residential/Lodging 1.18 — 1.35 1.23
Restaurant / Bar — 2.66 1.77 1.43
Retail 1.23 2.39 1.48 1.37
Warehouse 0.79 .77 0.72 0.58
Weighted Average 1.14 — 1.16 1.08
3.1.1. Lighting Code Compliance
Each state regulates lighting using a lighting power allowance. Table 3.4 summarizes the
lighting power allowance applied to the particular buildings in the utility sample. For
Seattle, there is a separate code that applies to buildings in that jurisdiction.
Table 3.5 summarizes the level of compliance in the utility area and compares it to the
level of lighting code compliance in the state and region. It should be noted that for this
table only code compliance is summarized against the codes enforced in the jurisdiction
where the building is located.
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Table 3.4: Actual LPD Code Requirements (Watts/sq. ft.)
Mean Code
LPD Std. Dev. N
SCL 1.31 .33 28
Washington 1.26 0.38 146
Region 1.31 0.45 347
Table 3.5: Lighting Code Compliance Results
Compliance (%) N
SCL 89 28
Washington 78 146
Region 79 346
3.2. HVAC
Auditors collected HVAC system characterization information and detailed specifications for
heating, ventilation, and cooling equipment.
3.2.1. HVAC System Types
Table 3.6 summarizes the main HVAC systems and their delivery systems. HVAC
systems were categorized by system type and whether water was used to deliver space
conditioning (heating, cooling, or both). DX cooling units and gas furnaces are included
as hydronic if they used water as the main working fluid.
Descriptions of HVAC system types:
Zone/Unit Heater (Z/UH). Single-zone, ductless, direct heating and/or cooling
equipment as well as passive radiation baseboard and heated floors that utilize hot
water.
Single-Zone (SZ). CV, single-zone, ducted systems. This type of system is the most
common type of system and is generally associated with rooftop package systems.
Single-Zone VAV (SZ-VAV). Systems with a single-zone air handler with variable
flow. Flow in heating mode is at a minimum and then flow is ramped to meet cooling
or ventilation needs. Fan flow is varied using a VFD drive on the fan.
Multi-Zone (MZ). Systems with CV operation and reheat to condition spaces with
varying requirements. Typically, these systems have variable frequency drives
(VFD) on the central fans and many have VAV terminal boxes primarily to help with
balancing the system. The systems may have a few zones with variable flow
operation but overall the systems do not come close to meeting code requirements for
a variable flow system. These systems typically have very large heating requirements
to reheat cooled primary air. All of these systems utilize hot water reheat from a
boiler.
6
Variable Air Volume (VAV). All versions of VAV systems, fanless, series, and
parallel fan-powered. Reheat is typically needed and generally adds a significant
additional heating load. Generally, hot water reheat systems dominate hospital,
college, lodging, and educational buildings. Electric reheat dominates office areas.
Institutions and health services utilize an equivalent amount of hot water reheat and
electric reheat. This category includes the “under floor air distribution” systems often
used in LEED projects.
Heat Pump Loops (HPLP). Systems that use small heat pumps to supply zone-level
conditioning. The heat pumps are connected together with a water loop that is
conditioned in part by the diversity of the loads on the heat pump loop and in part by
a boiler and cooling tower that ensures that the loop temperature is maintained within
prescribed limits.
2 Pipe/4 Pipe Fan Coil (2/4-P). These systems are a variation on water loop
conditioning and use a chilled water and/or a hot water loop to feed fan coils in all
zones. This system is common in hospital and school settings and favored because it
affords a variety of control strategies to adjacent zones.
Table 3.6: HVAC Systems by Building Type (% Floor Area)
Building Type Z/U
H SZ SZ VAV MZ VAV HPLP 2/4 P Total
Assembly 2 81 17 0 0 0 0 100
College 40 60 0 0 0 0 0 100
Schools 16 30 0 0 12 30 11 100
Health Services 2 51 0 0 47 0 0 100
Hospital 2 6 0 43 49 0 0 100
Institution 2 27 9 11 52 0 0 100
Office 0 0 0 0 93 6 0 100
Residential / Lodging 4 30 0 18 0 48 0 100
Retail 9 86 0 1 4 0 0 100
Warehouse 100 0 0 0 0 0 0 100
Weighted Average (SCL) 10 43 2 8 23 12 3 100
Washington 17 52 1 6 15 4 5 100
Region 16 52 2 4 18 4 4 100
3.2.2. Heating Type
Table 3.7 summarizes the primary heating fuel by building type. Multi-zone reheat
systems with different primary coil fuel and reheat fuel are categorized by the reheat fuel
type. Heat pump fuel includes air source and water source heat pumps. Central plants
are included in the “other” category. This category includes remote plants that were not
part of the audited project. When the fuel type for building plants was recorded, it was
included in the appropriate fuel category rather than plant. “Other” heat sources included
oil, geothermal, heat recovery, and wood waste. In addition, if no heating system was
included (especially warehouse storage facilities) these were included under “other.”
7
We also compared the heating results to the summaries from the 2000 commercial
building audits and report (Baylon et al. 2001). As can be seen here there were
substantial differences between the building in this sample and the previous sample. This
is mostly explained by the relative importance of “office” uses in the 2000 study. In both
this sample and the previous sample, electric reheat accounts for about 90% of the built-
up VAV systems in Seattle. For cooling systems the saturations of chillers seems
unchanged between the two samples and the overall results of the 2002–2004 Baseline
Study.
Table 3.7: Heat Source Type by Building Type (% Floor Area)
Building Type Electric Heat
Pump
Natural
Gas Propane Other Total
Assembly 3 0 97 — 0 100
College 17 9 75 — 0 100
Schools 2 31 67 — 0 100
Grocery — — — — — 100
Health Services 1 11 88 — 0 100
Hospital 23 0 72 — 0 100
Institution 40 0 30 — 30 100
Office 94 6 0 — 0 100
Other — — — — — 100
Residential / Lodging 4 62 33 — 0 100
Restaurant / Bar — — — — — 100
Retail 4 30 66 — 0 100
Warehouse 0 0 100 — 0 100
Weighted Average (SCL) 14 20 60 — 5 100
2000 Average 58 1 22 — 17 100
Washington 15 10 69 4 2 100
Region 12 9 72 3 4 100
3.2.3. Cooling Type
The list below describes the various cooling types assessed in the study. Table 3.8
summarizes the primary cooling types by building type:
Direct Expansion (DX) Cooling. Dominates the cooling sources described here.
These systems are typically associated with packaged single-zone, constant volume
equipment though roughly 40% of all VAV systems also utilize DX cooling.
Chillers. Make up the next most common cooling type. These chillers typically
provide chilled water to fan coils or other air handlers throughout the building. Air-
cooled units represent a total of 60% of all chiller capacity installed.
Water Source Heat Pumps (WSHP). Refers to equipment served by a water loop.
These systems typically utilize a cooling tower to dump loop heat.
Evaporative Cooling is used very sparingly. Most of the evaporative cooling
reported results from a single home improvement chain.
Cold Ground Water. Utilized directly by a few buildings to provide cooling.
8
Economizer-Only. Cooling utilized in all states. In this case, an air handler has a
full economizer setting that is activated by a cooling thermostat. No additional
mechanical cooling is provided in these systems.
No Cooling. A large fraction of building floor area has no cooling. These areas are
dominated by warehouse type activities.
Table 3.8: Cooling Source Type (% Floor Area)
Building Type DX WSHP Evap Chiller Plant Ground Econo None
Assembly 88 0 0 0 — — 6 6
College 60 0 0 0 — — 0 40
Schools 11 30 0 20 — — 6 34
Grocery 0 0 0 0 — — 0 0
Health Services 49 0 0 47 — — 0 4
Hospital 6 0 0 91 — — 0 2
Institution 56 0 0 26 — — 15 3
Office 2 6 0 91 — — 0 1
Other 0 0 0 0 — — 0 0
Residential / Lodging 20 48 3 0 — — 23 7
Restaurant / Bar 0 0 0 0 — — 0 0
Retail 88 0 0 0 — — 0 12
Warehouse 31 0 0 0 — — 0 69
Weighted Average
(SCL)
44 11 0 23 — — 6 15
2000 Average 75 — — 18 — — 8
Washington 49 4 1 17 2 0 5 23
Region 53 4 1 17 2 0 4 20
3.2.4. HVAC Code Compliance
Where possible, auditors collected detailed capacity and efficiency information on the
HVAC equipment found in the buildings. These data often came from plans, equipment
nameplates, O&M manuals, and occasionally manufacturers’ websites.
Each piece of equipment was assigned an energy code minimum efficiency based upon
the equipment tables adopted by the applicable code. For Idaho and Montana the codes
utilized the ASHRAE 90.1-1999 base values throughout the design window so those
were chosen as the applicable code values. Washington and Oregon adopted the
ASHRAE 90.1-1999 October 29, 2001 efficiency values in early 2002, so those values
were used for buildings there. Note that ASHRAE Standard 90.1 has become a de facto
manufacturing standard, so newly made equipment generally complies with the current
standard. The problem is that there are several effective dates for enforcing this standard
and it does not apply to equipment already manufactured.
Table 3.9 shows the result of the equipment review for cooling equipment. Table 3.10
shows the results of the review of heating equipment. In both cases the compliance rate
is based on the code tables enforced in the 2001 codes.
9
Cooling equipment types:
Air conditioning equipment (AC) is the most common type of package cooling
equipment. The compressor is usually installed with a gas burner or furnace for
heating in either a package or as a split system. This category also includes split
system AC and large AC equipment in built-up systems.
Heat pumps include any and all air conditioning equipment with a reversing valve
and compressor drive heating mode. In smaller sizes (less than six tons) the rating
used is a SEER (a weighted average of performance in BTU/W in three different
operating conditions at 82°F); for larger sizes the EER is the primary rating measure
(BTU/W at a single weighting point, 95°F).
Packaged Terminal Air Conditioning (PTAC) are generally small, through-the-
wall, single-zone units with local control of temperature and air flow. These are very
common in lodging and other residential applications.
Water Source Heat Pumps (WSHP) refers to equipment served by a water loop.
These systems typically utilize a cooling tower to dump loop heat.
Table 3.9: Average Cooling Equipment Efficiency and Code Compliance (SCL Sample)
Cooling
Equipment
Seattle Region
Install Code Compliance
%
Install Compliance %
Cooling Package SEER/EER Efficiency
AC 10.5 9.7 84 10.5 85
HP 10.0 10.1 8 10.4 69
PTAC 11.0 9.9 100 10.5 100
WSHP 13.0 11.9 100 14.3 100
Chiller COP Efficiency
Air 2.9 2.8 90 3.0 95
Water 9.1 6.1 100 7.0 100
Heating equipment types:
Heat Pump (HP). All unitary heat pump equipment regulated under the HVAC
efficiency tables. These units are regulated based on size and configuration. The
efficiency shown here is the weighted average of the each heat pump observed in this
sample.
Packaged Terminal Heat Pump (PTHP). Generally small, through-the-wall heat
pumps with both compressor and condenser in a single package.
Water Source Heat Pumps (WSHP). Equipment served by a water loop. These
systems typically utilize a boiler to maintain loop temperature in heating mode.
Furnace/Unit Heater (FURN/UH). Single-zone air handlers with combustion heat
exchanger or electric resistance coils.
Boiler. The primary equipment of hot water heating systems, usually supplying heat
through a water loop.
10
Table 3.10: Average Heating Efficiency and Code Compliance (SCL Sample)
Heating Equipment Seattle Region
Efficiency Compliance % Efficiency Compliance %
Electric
HP 3.5 9 3.3 93
PTHP 3.4 100 3.1 100
WSHP 4.0 86 4.1 94
FURN/UH 1.0 100 1.0 100
Combustion
FURN/UH .82 100 .82 98
Boiler .87 100 .86 100
3.3. Building Envelope
Construction techniques and insulation strategies vary dramatically within the commercial
sector. The techniques used are determined largely by building type and to a lesser degree
location. Insulation levels are driven by code requirements that do not distinguish between
individual building types. One exception to this is the use of semi-heated spaces in the
Washington codes and the use of unheated spaces in all regional codes. Table 3.11 summarizes
the building heat loss rate for the audited buildings. Given the timing of the audit, the heat loss
rate often had to be calculated without direct observation of the components. In most cases,
architectural details and specifications were used to determine the insulation values and
performance of particular components. In cases where these sources were not available, the
default values were used from the applicable code requirements. The overall heat loss rate has
been normalized by conditioned floor area. This allows the relative heat loss rate of each
building type in the samples to be reasonably comparable. The Seattle sample has about 22%
lower overall heat loss rate in spite of the increased window area shown in Table 3.12.
Table 3.11: Building Heat Loss Rate (UA/sq. ft.)
Building Type SCL N Region N
Assembly 0.26 2 0.19 8
College 0.11 1 0.11 9
Schools 0.17 7 0.14 67
Grocery — 0 0.14 18
Health Services 0.13 2 0.14 16
Hospital 0.10 4 0.11 25
Institution 0.13 3 0.17 24
Office 0.11 1 0.16 26
Other — 0 0.17 9
Residential / Lodging 0.10 4 0.12 18
Restaurant / Bar — 0 0.20 8
Retail 0.12 7 0.21 78
Warehouse 0.25 1 0.26 40
Weighted Average 0.14 32 0.18 346
11
Building components have not changed drastically since the last study. However, glazing
performance has increased to the point that low-ε coatings are nearly ubiquitous and solar
heat gain coefficients (SHGC) have been reduced. These performance improvements are
partially offset by the design trend of increased glazing areas.
The summary in Table 3.12 shows that the percentage of window area to total window area is
significantly greater in Seattle than in the state and regional level. This is true even though
the sample size for this utility service territory is only 31 buildings. This summary does not
include the two LEED buildings that were not part of the sample frame for either the city or
the region.
The distribution of high performance windows in Table 3.13 summarizes the U-value of the
windows observed. These performance values have been binned into four major categories.
This simplification was necessary to allow estimation in the absence of direct installer or
manufacturer tests of the overall window performance. Table 3.13 also reflects the improved
window performance in the Seattle sample that roughly counterbalances the increased
window area. The values in this table are the fraction of the total window area in each
building type that is assigned to the particular performance bin. For example, 26% of the
windows in the School sector are assigned values between class 30 (U=0.30) and Class 40
(U=0.40).
When the results of the 2002-2004 sample are compared to the results of the previous sample
(which were largely permitted in 1998 and 1999) there is a striking improvement in window
U-value. In some building types (especially “office”) window areas increased, but on the
whole no clear trend toward higher glazing percentage appeared across building types.
Table 3.12: Window Area by Building Type (% of Gross Wall)
Building Type SCL 2000
Sample Washington Region
Assembly 23 — 16 16
College 19 31 24 20
Schools 15 — 13 14
Grocery — 14 6 9
Health Services 34 18 26 26
Hospital 34 — 21 21
Institution 25 — 15 18
Office 55 37 31 29
Other — 19 4 10
Residential/Lodging — — 27 25
Restaurant / Bar 23 — 11 16
Retail 12 18 11 11
Warehouse 10 1 5 4
Weighted Average 22 29 15 15
12
Table 3.13: Window U-Factor by Building Type (% of Glazing Area)
Building Type U-Factor Class (100 x U-factor)
30-40 41-50 51-60 >60
Assembly 1 99 0 0
College 100 0 0 0
Schools 26 66 8 0
Grocery — — — —
Health Services 0 59 42 0
Hospital 84 2 14 0
Institution 80 20 0 0
Office 79 0 21 0
Other — — — —
Residential / Lodging 92 8 0 0
Restaurant / Bar — — — —
Retail 1 83 17 0
Warehouse 0 0 0 100
Weighted Average
(SCL)
46 40 10 4
SCL 2000 Average — 27 39 33
Washington 39 33 16 13
Region 42 36 12 10
3.3.1. Solar Heat Gain Coefficient
The solar heat gain coefficient (SHGC) is largely a function of the glazing properties
rather than the frame properties. SHGC varies substantially with the types of low-ε
coating and types of glass substrate to which they are applied. The auditors attempted to
retrieve SHGC information directly from the building, the window specifications, the
window installer specifications, or the architect. Shading components were then
combined with frame information to estimate SHGC, organized into bins as shown in
Table 3.14. As with heating performance, the Seattle buildings have lower SHGC than
the remainder of the sample. This is largely the result of the addition of low-ε coatings
required to bring the overall window area into compliance.
Table 3.14: Window SHGC Category (% of Window Area)
SHGC Class (100 x U-factor)
17-35 35-54 55-86 Clear
SCL 55 26 19 0
Washington 42 35 24 2
Region 43 37 19 2
3.3.2. Building Envelope Code Compliance
Envelope code requirements differ in both style and substance across the various state
codes. As with other components in this study, the code review was based on the code
enforced in each jurisdiction in 2001. In Table 3.15, code compliance was calculated for
both the 2001 code and the 2005 code, which represents the code that would have been in
place in all of the jurisdictions in 2005.
13
The Seattle Energy Code was updated during the period of this study. Trade-offs were
evaluated using the code available in 2001. As can be seen in Table 3.15, the impact of
subsequent revisions would lower the potential compliance substantially. The table
shows that for both the SCL and Washington state samples, the percentage of envelope
code compliance would decrease somewhat due to the tightened code requirements of the
2005 code.
Table 3.15: Envelope Code Compliance by Code (% and N)
State Code Year
2001 2005 N
SCL 90 82 32
Washington 94 76 148
3.4. Building Commissioning
During the review, auditors examined plans for indication of commissioning, asked on-site
staff whether commissioning was completed, and looked for commissioning documents
on-site. Table 3.16 summarizes the observed commissioning as gathered from available
documentation or from direct conversations with the building operators. There are several
large buildings in the Retail and Lodging sectors that did not report commissioning and no
evidence of commissioning reports could be found. This resulted in reduced overall
commissioning fractions although in most building types commissioning was used in the
Seattle sample. This was about twice the rate observed in the remainder of the state and
region.
Commissioning included comprehensive commissioning with reports and deficiency lists,
sites with plan notes requiring witnessed operational testing, and cases where the building
representative stated commissioning had been done. In many cases, the building
representatives participating in the audit process were not involved in construction of the
project and so may not have been aware of commissioning activities. As a result, levels of
commissioning were likely higher than this summary shows.
During this period “completion requirements” were a requirement in Washington state. It is
likely that some commissioning steps were taken in every building, however, the auditors
were not able to review commissioning documents on site and the building operator was not
aware of actual commissioning in these cases.
14
Table 3.16: Reported Commissioning by Building Type
Building Type % of Buildings
Reporting
Commissioning
% of Floor Area
Commissioned
Assembly 0 0
College — —
Schools 100 100
Grocery — —
Health Services 100 100
Hospital 100 100
Institution 100 100
Office 100 100
Other — —
Residential / Lodging 39 31
Restaurant / Bar — —
Retail 4 14
Warehouse 0 0
Weighted Average (SCL) 50 69
Washington 27 43
Region 21 37
3.5. Operations / Training
Buildings in this sample have a large amount of digital controls that allow operators more
access to individual schedules and zone controls for both HVAC and lighting.
Unfortunately, the training available for the actual building operators seems to be minimal.
Even in complex buildings when individual operators were asked, they usually did not have
any training beyond the manuals that may have been included in the building documentation.
These were usually very hard to find and even harder to discern. The commissioning
requirements under the Washington code and the ASHRAE code require commissioners to
provide a level of documentation and training to the building owner or operator. Table 3.17
shows the percent of operators interviewed that received some degree of direct operator
training either in the specifics of their particular building or as part of professionally
sponsored training for building operators. As Table 3.17 shows, approximately 30% of the
building operators in the region (that were on site during the audit period) had completed
some sort of building operator training. The buildings in the Puget Sound region were
roughly consistent with the rest of the region.
Table 3.17: Operator Training as Reported by Building Operators (% of Buildings)
Type of Training Reported
BOC† Other None
SCL 3 9 88
Washington 13 9 78
Region 13 21 68 † BOC = Building Operator Certification
15
3.6. LEED® Buildings
In this sample, eight Seattle buildings had been LEED certified by the USGBC. This group
represented approximately a third of the overall sample and over 50% of the total floor area
reviewed in Seattle. The impact of this sample was increased somewhat by the addition of
two buildings beyond the buildings that were drawn from either the regional random sample
or the enhanced sample for Seattle. Even without these added buildings, 43% of the building
area in the SCL sample was LEED certified. A detailed description of these buildings and a
comparison with other LEED buildings is included in a separate report (Baylon and Storm
2008). Table 3.18 summarizes the LEED certified buildings included in this report.
Since the LEED program was only proposed in 1999, the cohort of buildings sampled in this
study is among the early adopters for this program. In virtually every case, their LEED
participation corresponded to their participation in SCL’s “ESS” commercial energy
efficiency incentive programs.
Table 3.18: LEED Certified Buildings Observed (N)
4. Energy Use and Energy-Use Intensities (EUIs) As a part of the field protocol developed for the 2002–2004 Baseline Study auditors were asked
to get signed releases allowing the utility to release energy bills. This was supplemented with
meter numbers when available. Several problems arose in the regional sample that reduced the
number of bills that could be collected. In the SCL sample about 70% of the buildings
participated and had sufficient bills to summarize their particular energy use. In the regional
sample as a whole, only about 55% of the sample could be included in this analysis. A detailed
comparison and explanation of the development of this billing analysis is included in the EUI
supplement (Baylon and Robison 2008) to the 2002–2004 Baseline Study. In addition, the
LEED sample also includes additional summaries of the energy bills from that subset of the
regional sample. For this summary we have included a total line that is meant to give the
weighted average of the EUIs across each sample. While such a summary is traditional in
reporting EUI data, it is potentially very misleading since the average depends on the relative
number of buildings with large energy use (e.g., Hospitals, Groceries) and low energy use (e.g.,
Warehouses). The sample as it finally appears in these summaries is a subset of the initial
representative sample and, unfortunately, the amount of non-response in developing the EUIs
compromises the meaning of the “Total” entry.
For this summary the energy use of each building was normalized by the size of the building. In
addition, the various energy and fuel use was converted to a set of common units. KBtu/sq. ft.
was the resulting Energy Use Intensity (EUI) used in evaluating the buildings of these samples
and comparing to other datasets. For this purpose the building area was defined as the
LEED Certification
Certified Gold Silver Total
SCL 2 2 4 8
Washington 3 4 5 12
Region 3 10 10 23
16
conditioned, enclosed area of the building. In the case of “warehouse” use, the area used
generally included all the storage area that was generally “semi heated” but included lights and
other equipment. In all other building types the areas of parking garages, outdoor sales areas,
outdoor parking areas and unconditioned mechanical penthouses or similar spaces were not
included in the building areas used in calculating the EUIs. This definition was used by the
CBECS authors and the CBSA data was adjusted to be consistent with this approach.
Table 4.1 shows the relationships between EUIs observed in the Seattle buildings and the EUIs
observed in similar buildings in the state and regional samples. These comparison values are
calculated with the building area as the only weighting. The case weighting was abandoned
when EUIs could not be developed on a large portion of the sample. Only the total line preserves
the original weighting in the hope of reducing the bias in such a calculation. Table 4.2 uses the
same data but recalculates data into kWh/ sq. ft.
Table 4.1: Total EUI summary (kBtu/sq. ft.)
Building Type Seattle Washington Region
Mean SD Obs. Mean SD Obs. Mean SD Obs.
Assembly 68.6 1.0 2 64.1 15.0 4 83.1 37.1 7
Education 45.4 16.8 4 72.3 17.6 15 61.4 18.2 34
Health Services 98.4 7.3 2 119.9 27.3 6 111.8 35.3 10
Hospital 249.2 2.4 2 184.5 34.9 6 193.5 46.6 10
Institution 69.3 19.9 4 71.6 20.7 11 75.2 29.7 20
Office 59.9 15.5 2 60.2 12.4 4 71.7 26.1 19
Retail 112.7 36.9 5 111.1 33.8 17 95.5 34.9 40
Warehouse 84.1 0.0 1 88.8 55.1 12 70.5 58.1 25
Total 84.1 41.8 22 87.0 46.8 75 77.8 43.0 165
Table 4.2: Total EUI summary (kWh/sq. ft.)
Building Type Seattle Washington Region
Mean SD Obs. Mean SD Obs. Mean SD Obs.
Assembly 20.1 0.3 2 18.8 4.4 4 24.3 10.9 7
Education 13.3 4.9 4 21.2 5.2 15 18.0 5.3 34
Health Services 28.8 2.1 2 35.1 8.0 6 32.8 10.4 10
Hospital 73.0 0.7 2 54.1 10.2 6 56.7 13.7 10
Institution 20.3 5.8 4 21.0 6.1 11 22.0 8.7 20
Office 17.6 4.6 2 17.6 3.6 4 21.0 7.7 19
Retail 33.0 10.8 5 32.5 9.9 17 28.0 10.2 40
Warehouse 24.6 0.0 1 26.0 16.2 12 20.7 17.0 25
Total 24.6 12.2 22 26.0 12.5 75 22.4 14.2 165
17
Table 4.3 shows the electric only EUIs for the samples. These values are summarized from the
billing information provided by the various utilities and reflect the electric use independent of
heating type, or other factors.
Table 4.3: Electric Only EUI summary (kWh/sq. ft.)
Building Type Seattle Washington Region
Mean SD Obs. Mean SD Obs. Mean SD Obs.
Assembly 7.6 0.4 2 7.2 1.7 4 13.3 6.8 7
Education 10.1 11.4 4 10.9 4.2 15 9.6 3.5 34
Health Services 12.9 0.0 1 14.9 6.2 5 14.3 6.6 9
Hospital 37.2 9.2 2 25.1 8.2 6 25.3 8.4 10
Institution 15.2 3.0 4 14.9 3.0 11 15.4 3.7 20
Office 15.7 1.7 2 15.8 1.5 4 17.8 7.0 19
Retail 23.6 5.9 5 24.6 5.8 17 21.6 6.0 40
Warehouse 19.5 0.0 1 19.8 11.6 12 15.1 11.7 25
Total 18.2 7.9 21 18.5 9.4 74 16.5 9.0 164
Table 4.4 shows the comparable EUIs from the Commercial Building Stock Assessment (CBSA)
sample (Kema-Xenergy 2003) and the Commercial Building Energy Consumption Survey
(CBECS) sample (EIA 2003) in kBtu for all energy sources used in the buildings. The CBSA is
a regional summary based on audits conducted on new building stocks from 1990 to 2000 soon
after they were constructed. The regional sample is restricted to buildings of the same type as
the SCL sample for which data was available. Weighting is compiled by building type and not
designed to summarize across building types to the entire commercial sector. The CBECS
summaries give an indication of the scale of the EUIs observed in the SCL sample, however, it is
included here as the standard table used to assess energy performance in various programs
including LEED and the “2030 Challenge.”
Table 4.4: Adjusted EUIs from CBSA Regional Study (1990-2000 Cohorts) and CBECS
Building Type SCL CBSA CBECS
Mean Mean Std. Dev. N Post 1990 All
Assembly 68.6 — — — 81.5 68.7
Education 43.5 83.8 73.7 7 80.6 83.1
Health Services 98.2 76.5 48.4 8 84.4 94.6
Hospital 250.1 — — — — 249.2
Institution 69.3 — — — 119.7 115.8
Office 59.4 81.8 46.7 46 88.0 92.9
Retail 112.7 139.0 71.6 32 94.4 91.3
Warehouse 84.1 83.0 46.2 11 33.3 45.2
18
In this relatively small sample, the EUI comparisons between the regional sample and the Seattle
buildings suggest that the energy use in these two sets are comparable. Indeed, within the
precision of the sample size and standard there is only limited statistically significant differences
between these two datasets:
Especially when compared to the older regional sample and the CBECS sample the education
sector sample in Seattle has significant savings. This difference is less significant when
comparing to the regional or state 2002-2004 sample, although there is still some noticeable
difference.
In the office sector, two large buildings with large and active server loads were not included
in the summary of the regional samples. Had these buildings been included, the office sector
EUI would have increased over 40% and the difference between the Seattle buildings and the
regional or state sample would have been significant. We elected to remove these two
buildings because with such small samples very small sample differences can result in
unrealistic comparisons. In this case, the server loads were not atypical of some Seattle
buildings, but no such buildings appeared in the Seattle sample.
The retail sector is compromised by the integration of grocery stores into more traditional
“big box” stores. The grocery application adds a substantial refrigeration and heating load to
those buildings. Even in very large stores this combination increases the EUI by 70 to
100 percent. As a result, the EUIs calculated for any particular retail sample is largely
determined by the fraction of grocery application which incidentally occurs within the stores
in the sample.
5. Interviews with Architects and Designers Interviews were conducted with the architects and engineers involved in the design of the
buildings surveyed.
The goals of the interviews were to:
Understand what energy codes were used and how they were enforced.
Learn about current trends in attitudes toward energy efficiency/energy codes.
Determine the importance of energy efficiency in the design process.
The interviews focused on the decision-making process in the individual building projects.
Because of the time between the planning phases of these projects and the actual interviews
(typically at least five years or longer) the interviews tended to focus more on current attitudes
toward energy efficiency and energy codes and less on the decisions made specifically for
buildings in this study.
In this section, the responses from the individual utility territories are compared to the responses
from the rest of the regional survey. While the main study compares the results in this survey to
previous interview results in the regional survey done in 1999, for this summary the data was not
available to make such comparisons in individual service territories. Thus in these summaries
comparisons are made with the regional results.
19
Auditors also performed on-site interviews with building operators and site managers. These
interviews sometimes supplemented, or were comparable to, the interviews with designers but
the time span between the design phase of these projects and the designer interviews limited the
utility of such comparisons.
5.1. Interview Sample
Table 5.1 shows the distribution of the interviews conducted in the Seattle City Light service
territory and how this compares with the rest of the regional survey.
Table 5.1: Interview Sample Distribution by Design Role
Design Role SCL Washington Region
N % N % N %
Architect / Envelope
Designer 11 52 37 51 83 55
Mechanical Engineer 9 43 33 45 58 38
Mechanical Contractor 0 0 0 4 3
Other 1 5 3 4 6 4
Total 21 100 73 100 151 100
5.2. Energy Codes
As with previous studies, interviews tried to gauge the attitude and acceptance of the energy
codes. While there were complaints, the level of acceptance in these types of surveys has
increased over the last two decades. In some cases, architects even suggested that the code
be made even more stringent.
Interviewees were asked if there were any elements of the energy code they considered to be
poorly thought-out or not cost-effective. The results are presented in Table 5.2. Only about
60% of the interviewees answered this question with the majority arguing that the codes were
too strict. This was less true in jurisdiction with little or no enforcement. The Seattle code is
among the strictest and most heavily enforced codes in the nation. This level of enforcement
is illustrated by the amount of feedback that designers received (Table 5.3).
Table 5.2: Reactions to Energy Code Provisions
Code Problems SCL Washington Region
N % N % N %
Too Strict 11 58 28 58 43 44
Too Lenient 1 5 1 2 7 7
Poor Wording 2 11 7 15 16 16
Internal Conflicts 3 19 7 15 15 15
Not Enforced 0 0 2 4 3 3
Flexible 0 0 0 0 1 1
Good Code 0 0 0 0 2 2
Deficient Coverage 1 5 3 6 11 11
Total 19 100 48 100 98 100
20
Table 5.3: Plan Reviewer or Building Official Feedback (%)
Feedback after Plan
Examination SCL Washington Region
Yes 57 52 46
No 38 41 51
Don’t Remember 5 7 3
The majority of respondents said they design their buildings in accordance with the relevant
energy code. Respondents also indicated that they sometimes worked to exceed minimum
lighting, HVAC, and envelope requirements.
Table 5.4 shows that many designers assert that they often exceed code requirements in some
components. In Seattle, the designers seemed to be convinced that they often exceeded the
code requirements.
Table 5.4: Percent of Respondents Claiming “Beyond Code” in their Designs
Component SCL Washington
Regional
Total
% % %
Lighting 45 38 37
HVAC 41 36 49
Envelope 64 44 40
5.3. Attitudes Toward Energy Efficiency
Interviewees were questioned about how important incorporating energy efficient features
were to members of the design team. Table 5.5 shows that about half of the regional sample
identified energy efficiency as an important factor. The Seattle area largely mimicked the
region as a whole and represented some increase over the rest of the Washington sample.
Table 5.5: Importance of Energy Efficiency to the Design Team (%)
Level of
Importance SCL Washington Region
Not at all 18 26 48
Moderate 23 30 37
Very 59 44 56
The interviews assessed how energy efficiency decisions are made and if design practices
have changed since the 1999 interviews. Individual design professionals still make the
majority of energy efficiency decisions; however, team decision making is becoming more
prevalent and design professionals are changing their practices to reflect a growing client
demand for energy efficiency.
Table 5.6 illustrates the responses to questions about the use of LEED in the design process.
In general substantial interest was shown in the LEED process and LEED certification.
21
However, outside of Seattle this interest did not result in much client interest. By the end of
the time the projects were completed only a small number had actually pursued LEED
certification. Of all the areas in the regional survey, Seattle City Light had the largest
number of LEED buildings implemented after the initial interest. It should be pointed out
that the LEED program was only just starting when buildings in this sample were in planning
stages. Later the support of various utility and state agencies might close the apparent
difference between Seattle and the rest of the region.
Table 5.6: LEED® Requested by Clients
LEED Requested
in SCL
LEED Included
in SCL
LEED Requested
in Washington
LEED Requested
in Region
LEED Included
in Region
% % % % %
Yes 36 32 6 8 5
No 64 68 94 92 95
N/A 0 0 3 1 1
N 31 22 73 150 150
Interviewees were asked to suggest the best opportunities to promote energy efficiency.
Table 5.7 presents the set of responses to this request. Respondents indicated that the best
way to promote energy efficiency is to provide more education on life-cycle costs and on
potential energy efficiency options. In many cases throughout this review it was apparent
that the distinction between the goals of the energy efficiency and the implementation of that
efficiency is disconnected. It appears from our interview respondents that at least this group
felt the utility of education would be helpful. Developing case studies showing real world
buildings and their energy use was the most common educational tool mentioned. Providing
more financial incentives in the form of either utility rebates/incentives or tax credits was
another way of supporting energy efficiency mentioned.
Table 5.7: Opportunities to Promote Energy Efficiency
Best Opportunities SCL Washington Region
N % N % N %
Education 15 56 51 61 106 63
Financial Incentives 5 18 11 13 25 15
Stronger code 4 15 8 10 12 7
Increase Energy Costs 0 0 5 6 8 5
Technology Changes 2 7 5 6 7 4
Keep-up with the Jones
Marketing 1 4 1 1 5 3
LEED® 0 0 1 1 4 2
Enforce code 0 0 2 2 2 1
Total 27 100 84 100 169 100
22
6. Overall Observations The sample and buildings reviewed in this survey were designed to represent the Seattle building
stock separately. As such the comparison to the regional samples reflect both the differences in
the attitudes and design approaches used in this locality and the different building types
reflective of a built-up urban area.
Building Size and Type. As with any sample some of the nature of comparison is
influenced by the buildings that happened to be built in the city in the construction
window used to constrain the sample. This process is further influenced by the level of
participation from the building operators and owners in the audits and billing analysis.
For this sample, the buildings in the SCL sample were 25% larger than comparable
buildings in the regional sample. This difference vanishes when buildings are compared
to other urbanized areas throughout the region.
Envelope Characteristics. The most striking features of the Seattle buildings is a large
amount of glazing in the large Seattle buildings. This is partly the result of building size,
but even with that taken into account the sample has about 46% more glazing area as a
percent of wall area than the regional sample (see Table 3.12). Indeed this spread is
apparent (or even greater) when the data is subdivided into separate states or utility
regions. It does appear that the trend toward greater glazing area is balanced by a trend
toward higher performance glass and higher performance in other building components.
This combination results in a 22% reduction in building heat loss rates in Seattle
compared to the regional heat loss rates (see bottom row of Table 3.11).
HVAC Characteristics. The nature of the Seattle building population seems to result in
more complex and more controlled HVAC systems than the region as a whole. The
incidence of built-up VAV systems (particularly with electric reheat) was almost 30%
higher in Seattle than the regional sample as a whole. Conversely, the use of
single-zone-Dx systems was only about 60% as likely as the regional sample as a whole.
The more complex HVAC systems were a focus of the utility incentive programs and
several innovative HVAC system designs were observed in this service territory. For the
simple, single-zone, HVAC systems the efficiency and controls were more typical of
building observed throughout the region.
Lighting Characteristics. The actual average LPD in the entire Seattle sample was 1.14
Watts/sq. ft.., or 13% lower than the average Seattle Energy Code LPD of 1.31 across
building types combined (see Table 3.3 and Table 3.4). However, the lighting systems in
the SCL sample as a whole were similar to the region and state samples. In most building
types the distinctions in actual average LPDs between any of these samples was minor.
One exception to this was the SCL sample of offices. In this case, the LPDs of the Seattle
sample of office buildings were almost 30% less than the regional sample as a whole. The
average LPD in the Seattle office buildings was 0.74 Watts/sq. ft., or 22% more efficient
than the Seattle Energy Code requirement of 0.95 in office buildings. And although not
statistically significant, the LPD in Seattle’s institutional buildings, residential/lodging,
and retail buildings were slightly lower than in the regional sample (see Table 3.3).
23
Similarly, lighting controls were in use much more often in the SCL sample. Daylighting
controls, for example were more than twice as likely to be used in the Seattle buildings
than in the state sample, and over three times as likely than in the regional sample (see
Table 3.2). This was partly due to the use of daylighting as part of the LEED program,
which was supported by the utility and has become quite popular in this area. This seems
to represent a significant difference with the rest of the regional sample.
Overall Energy Use. The EUIs of the Seattle buildings were not generally much different
than comparable building types in the region as a whole. It appears, however, that when
compared to the CBECS national benchmarks the SCL sample does have significantly
lower EUIs in at least some building types. Since this comparison was made with a large
number of buildings built throughout the country after 1990, the improvements are not
surprising. When compared to the Post-1990 cohort in the CBSA data there are
differences in some building types, but the small sample sizes tend to reduce the utility of
these comparisons.
Code Compliance and Designer Interviews. On the whole, the level of code compliance
in Seattle is comparable to the other sample throughout the region. In the case of Seattle,
the energy code is generally more stringent and more enforced than in most other areas of
the region. Nevertheless, the level of code compliance is comparable. There were some
differences in individual building components:
Lighting Code compliance. The actual lighting efficiency in the Seattle sample was
89% in compliance with the Seattle Energy Code (SEC). This is 1l% more compliant
than the level of compliance in the Washington and regional samples (see Table 3.5).
HVAC Code Compliance. The compliance with equipment efficiency standards in
the Seattle sample was about 82% for cooling equipment and 99% for heating
equipment. This compares to about 87% for cooling equipment and 98% for heating
equipment in the region as a whole.
Envelope Code compliance. The level of envelope code compliance is mixed. For
the 2001 code, the Seattle sample buildings were 90% compliant, slightly lower that
the 94% compliance in the Washington sample (excluding Seattle).
Designer Attitudes. A more striking finding came from the interviews conducted
with the architects and engineers involved in the SCL sample. This group was more
interested and more willing to develop building designs that “exceeded” code
requirements. About 20% more respondents asserted that they attempted to exceed the
code in the buildings and systems they designed. For the most part, this group seems
to welcome the Seattle energy code and be willing to comply with it or with a more
stringent code.
Much of the differences observed in the SCL sample could be traced to the participation and use
of the LEED certification system as a basis for marketing and assessing energy efficiency. The
24
assessment of that program in the SCL service territory is included in a separate document. For
the overall SCL sample, the impact of the LEED buildings is not particularly striking. While
many of the more advanced control and HVAC systems are associated with those buildings,
overall performance does not seem to be much improved at least within the statistical limitations
of this small sample. In many cases, the architectural or programmatic needs of the building
dominate the overall performance and the nuances brought by the sustainable design goals are
relatively less significant.
From the point of view of the architects and other professional interviewed, there seemed to be
an expanded interest in energy efficiency. There were numerous comments along the line that
education and direction from the utility would be well received. From this review it would
appear that such input is also necessary.
7. References
Baylon, David, and Mike Kennedy. 2008. Baseline Characteristics of the 2002-2004
Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:
Northwest Energy Efficiency Alliance.
Baylon, David, 2008, Comparison of LEED buildings in the Seattle City Light Service Area and
the 2004-2004 Pacific Northwest Commercial Building Stock, Seattle City Light, Seattle
Washington,
Baylon, David, Mike Kennedy, and Shelley Borelli. 2001. Baseline Characteristics of the
Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:
Northwest Energy Efficiency Alliance.
Baylon, David, and David Robison. 2008. Baseline Energy Use Intensities of the 2002-2004
Nonresidential Sector: Idaho, Montana, Oregon, and Washington. Portland, Oregon:
Northwest Energy Efficiency Alliance.
Baylon, David, and Poppy Storm. 2008. Comparison of Commercial LEED Buildings and
Non-LEED Buildings within the 2002-2004 Pacific Northwest Commercial Building Stock.
Proceedings of the 2008 ACEEE Summer Study. Washington DC: ACEEE.
Energy Information Administration. 2003. Commercial Buildings Energy Consumption Survey
(CBECS). http://www.eia.doe.gov/emeu/cbecs/
Kema-Xenergy, Inc. 2004. Assessment of the Commercial Building Stock in the Pacific
Northwest (CBSA). Portland, Oregon: Northwest Energy Efficiency Alliance.