23-365 Bainbridge 120KW Solar PV Evaluation Report 2024-04-08
110 James Street, Suite 106 | Edmonds, WA 98020
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COBI - 120kW Solar PV Evaluation
Assessment and recommendations for the
installation of a 120kW Solar PV system
Preliminary Assessment Report
4/3/2024
Prepared for:
City of Bainbridge Island
280 Madison Avenue North
Bainbridge Island, WA 98110
Bainbridge Island PV and Battery Storage
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Table of Contents
Executive Summary ........................................................................................................................ 3
Project Overview............................................................................................................................................................. 3
Initial Criteria Factors ..................................................................................................................................................... 3
Methodology ..................................................................................................................................................................... 3
Final Criteria Factors ...................................................................................................................................................... 4
Washington State Ferries - Bainbridge Terminal OHL Walkway .............................................. 5
Existing Conditions .......................................................................................................................................................... 5
Site Overview .................................................................................................................................................................... 5
Structure Overview ........................................................................................................................................................... 5
Electrical Overview ........................................................................................................................................................... 5
Recommendations and Approach ............................................................................................................................... 5
System Sizing ..................................................................................................................................................................... 5
Electrical Point of Connection and Required Upgrades for POC .................................................................................... 5
Washington State Ferries – Eagle Harbor Maintenance Building .............................................. 6
Existing Conditions .......................................................................................................................................................... 6
Site Overview .................................................................................................................................................................... 6
Building Overview ............................................................................................................................................................. 6
Structure Overview ........................................................................................................................................................... 6
Electrical Overview ........................................................................................................................................................... 6
Recommendations and Approach ............................................................................................................................... 6
System Sizing ..................................................................................................................................................................... 6
Electrical Point of Connection and Required Upgrades for POC .................................................................................... 6
Bainbridge Island Recreation Center ............................................................................................ 7
Existing Conditions .......................................................................................................................................................... 7
Site Overview .................................................................................................................................................................... 7
Building Overview ............................................................................................................................................................. 7
Electrical Overview ........................................................................................................................................................... 7
Recommendations and Approach ............................................................................................................................... 7
System Sizing ..................................................................................................................................................................... 7
Electrical Point of Connection and Required Upgrades for POC .................................................................................... 7
Fire Station #21 ............................................................................................................................... 8
Existing Conditions .......................................................................................................................................................... 8
Site Overview .................................................................................................................................................................... 8
Building Overview ............................................................................................................................................................. 8
Structure Overview ........................................................................................................................................................... 8
Electrical Overview ........................................................................................................................................................... 8
Recommendations and Approach ............................................................................................................................... 8
System Sizing ..................................................................................................................................................................... 8
Electrical Point of Connection and Required Upgrades for POC .................................................................................... 8
Woodward Middle School .............................................................................................................. 9
Existing Conditions .......................................................................................................................................................... 9
Site Overview .................................................................................................................................................................... 9
Building Overview ............................................................................................................................................................. 9
Structure Overview ........................................................................................................................................................... 9
Electrical Overview ........................................................................................................................................................... 9
Recommendations and Approach ............................................................................................................................... 9
System Sizing ..................................................................................................................................................................... 9
Electrical Point of Connection and Required Upgrades for POC .................................................................................... 9
Conclusion and Recommendations ............................................................................................. 10
Electrical Modifications Required .............................................................................................................................. 10
Summary of Sites and Recommended Site for the 120kW PV system ............................................................ 11
Exhibits .......................................................................................................................................... 12
Bainbridge Island PV and Battery Storage
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Executive Summary
Project Overview
The City of Bainbridge Island (City) seeks to identify a project site for a 120kW solar/photovoltaic (PV)
installation. The City prefers that a single site be identified to house the entire 120kW system.
The purpose of this report is to describe and evaluate five (5) potential sites, out of the seven (7) sites that
applied to the City of Bainbridge Island as candidates for 120kW solar/photovoltaic (PV). Following is a
list of sites that applied for the PV system:
1. Woodward Middle School
2. WSF Bainbridge Island Ferry Terminal -- Overhead Loading Structure
3. Fire Station 21
4. WSF Eagle Harbor Maintenance Facility Main Building
5. Bainbridge Island Recreation Center
6. Fire Station 22
7. Fire Station 23
Initial Criteria Factors
Criteria Explanation
Useable Roof Space Each site reported available roof space. This number was adjusted
based on record drawings to reflect useable roof space. The value
includes only south and west facing non-shaded roof areas. The
more available roof space maximizes the City’s funds by reducing
multiple site duplicate costs including mobilization, electrical
modifications, shutdowns, etc.
Sufficient Load The site should consume more power than generated by a PV
system. Limiting the generation to 90% of what is used ensures that
there is no over production of PV power.
Designed for Solar Ready Having a solar ready roof minimizes potential structure upgrades
and risks with adding new PV modules to the existing roof.
Age of Roof A roof replacement will require that the PV modules are temporarily
removed from the roof increasing risk of failure.
Methodology
After reviewing all applications, a decision matrix (Figure 1) was generated using the above criteria
established by the City and Design West Engineering/KPFF Structural (Consultant) with the primary goal
of maximizing the dollar/watt and available budget. The following sites were selected as potential
candidates for the 120kW PV system:
1. Woodward Middle School
2. Bainbridge Island Ferry Terminal -- Overhead Loading Structure
3. Fire Station 21
4. Eagle Harbor Maintenance Facility Main Building
5. Bainbridge Island Recreation Center
Bainbridge Island PV and Battery Storage
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Faculty from Design West Engineering and KPFF Structural completed a site visit for four of the selected
sites over two days (Site information collected from a previous PV assessment was used for the B.I.
Recreation Center site). Staff collected equipment information on the existing systems based on visible
name plate information and visual inspections.
The information gathered from the site was used for assessment and preliminary PV modeling. Additional
criteria were established and added to the decision matrix (Figure 2) in order to score each site and
provide a final ranking and recommendation.
Final Criteria Factors
Criteria Explanation
Useable Roof Space This number was further adjusted based on site visit data to reflect
observed shading. The more available roof space maximizes the
City’s funds by reducing multiple site duplicate costs including
mobilization, electrical modifications, shutdowns, etc.
Sufficient Load The site should consume more power than generated by a PV
system. Limiting the generation to 90% of what is used ensures that
there is no over production of PV power.
Designed for Solar Ready Having a solar ready roof minimizes potential structure upgrades
and risks with adding new PV modules to the existing roof.
Age of Roof A roof replacement will require that the PV modules are temporarily
removed from the roof increasing risk of failure.
Electrical Modifications The fewer amount of modifications required to the electrical system
results in more funds available for the PV system components
including modules and inverters.
Structural Impact The lower potential structural impacts and upgrades along with
fewer unknowns results in more funds available for the PV system
components including modules and inverters.
We will describe throughout this report where we have made assumptions, so that if additional
information becomes available, the data can be re-incorporated to achieve the most accurate results
possible.
Bainbridge Island PV and Battery Storage
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Washington State Ferries - Bainbridge Terminal OHL Walkway
Existing Conditions
Site Overview
The site is located at the Washington State Ferries Bainbridge Island (BI) Ferry Terminal. The existing
walkway was recently replaced with a new steel-fortified walkway anchored by concrete and steel
columns. The new walkway was designed to withstand a major earthquake and is solar ready. Based on
our cursory review of the site conditions, there do not appear to be any issues such as excessive shading
that might impact proposed PVmodules. The available space for PV is approximately 9,200 sq. ft. of
south-southwest facing roof structure.
Structure Overview
Refer to KPFF Structural Summary Exhibit B.1
Electrical Overview
The BI Ferry Terminal electrical system is served by Puget Sound Energy (PSE) through a 1000kVA pad
mounted transformer. The existing service is rated 1600 Amps 480V 3ph 3W. The transformer and
main service along with the PSE net meter are located in the parking lot on an equipment pad approx.
300 feet from the OHL structure. There is an existing 65kW PV array on the terminal building roof with
its disconnect located on the exterior lower level of the terminal building. The OHL structure is powered
by a 400 Amp 480V panel P and 225 Amp 208V panel L, located below the structure. There is an existing
300kW backup generator connected to Panel C through a 600 Amp ATS.
Recommendations and Approach
System Sizing
The PV system size for this site would be limited by the available south and west facing usable roof area.
Based on the available roof area, it is estimated that (56) modules could be placed on the southwest
roof. Assuming 430 watt panels, this would equate to a 24.08kWDC system size with an estimated
annual production of 28.31MWh. The annual consumption is 427MWh which is far greater than the
proposed system production.
Electrical Point of Connection and Required Upgrades for POC
The current PV system is connected directly to 480V Panel 4PX1 through a lockable AC disconnect. In
order to add PV, the new and existing system would need to be routed through a single AC disconnect
per PSE requirements. Additionally, the disconnect should be within sight of the main service
disconnect. This would require a new load side connection at the existing 1600 Amp main switchboard,
new trenching from the switchboard to a new disconnect at the OHL, and moving the existing PV system
to a new PV combiner panel.
Bainbridge Island PV and Battery Storage
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Washington State Ferries – Eagle Harbor Maintenance Building
Existing Conditions
Site Overview
The site is located just southwest of the Bainbridge Island Ferry Terminal. Based on our cursory review
of the site conditions, there do not appear to be any issues such as excessive shading that might impact
the PV modules.
Building Overview
The existing maintenance building has a footprint of approximately 19,000 square feet with
approximately 13,000 square feet of south facing roof space available for PV. The building is a 2-story
timber framed structure and is over 70 years old, however, a structural retrofit was completed in the
late 2000’s.
Structure Overview
Refer to KPFF Structural Summary Exhibit B.1
Electrical Overview
The existing building electrical system is served by Puget Sound Energy (PSE) through a 750kVA pad
mounted transformer. The existing service is rated 3000 Amps 480Y/277V 3 phase 4 wire. The service
consists of a main switchboard “SB400” located in an exterior outbuilding. From there, 480V feeds are
distributed throughout the facility. The maintenance building is fed from SB400 via a 1200 Amp
breaker. Existing switchboard 4SB1 powers the building through 480V feeders with transformers and
208V panelboards. There are plugins for portable roll up generators.
Recommendations and Approach
System Sizing
The building has a large south facing sloped roof area that is ideal for PV modules. Based on the
available roof area, it is estimated that a total of (288) modules could be placed on the upper and lower
south facing roof. Assuming 430 watt panels, this would equate to a 123.84kWDC system size with an
estimated annual production of 136.62MWh. The annual consumption is 1,900MWh which is far
greater than the proposed system production.
Electrical Point of Connection and Required Upgrades for POC
The PV system would be tied in at the main 3000 Amp switchboard SB400 located north of the
maintenance building. A 150 Amp breaker would be added to SB400 and serve as the load side
connection overcurrent device. From there a 200 Amp disconnect would be provided in the electrical
outbuilding adjacent from SB400. A 150 Amp feeder would be run from that location to the north
exterior of the maintenance building and a 100kW inverter. The inverter could be located adjacent to
switchboard 4SB1. DC conductors would be run from the inverter up to the roof PV modules. New PV
modules would be installed on the upper and lower south facing roof. The inverter would be mounted
on the building north exterior wall adjacent to switchboard 4SB1.
Bainbridge Island PV and Battery Storage
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Bainbridge Island Recreation Center
Existing Conditions
Site Overview
The Recreation Center site (formally Bainbridge Athletic Club) is located in the middle of the island and
consists of two buildings, an approximately 39,000 sq. ft. Recreation Building and a 14,000 sq. ft. prefab
metal Court Building. The site is generally flat in contour and the shading differs on each side of the
building.
Building Overview
The court building is a prefabricated web steel building constructed in 2010. The large south facing roof
is a standing seam metal roof in good condition. The south facing roof has full exposure and is a good
candidate for solar panels. According to the original building plans, the roof was designed for a snow
load of 25PSF and a live load of 20PSF.
Electrical Overview
The existing building electrical system is served by PSE through a 225kVA pad mounted transformer.
The existing service is rated 1000 Amps 277/480V 3 phase 4 wire. The main service is located in a
central electrical room inside the Rec Center building. 480V power is distributed to large loads such as
the elevator and HVAC units. Transformers are provided for 120/208V power to appliances and
receptacles. There is no existing backup generator.
Recommendations and Approach
System Sizing
The Main Rec Center Building west facing roof is adjacent to large trees. Due to potential shading
issues, it is not recommended to place new PV modules on the main Rec Center Building. The newer
Court building has a south facing sloped roof that is suitable for solar panels, however, it is not large
enough for a 120kW system. The largest size system would consist of approximately (100) 430 watt
modules with (4) 10kW string inverters and a system size of 43kWDC. The estimated annual production
is 47,350kWh, which would offset around 11% of the estimate average annual building energy use of
438,000 kWhr.
Electrical Point of Connection and Required Upgrades for POC
Since a large array is proposed at the Court Building, the inverters would need to be connected to the
existing 1000 Amp electrical service located at the Rec Building, rather than the small subpanel located
in the Court Building. Four new PV arrays would be provided, each connected to a 480V 10kW inverter.
The inverter output circuits would be combined in a 100 Amp 480V 3ph ‘DPV’ panel located inside the
building, adjacent to the inverters. The DPV panel would connect to the existing electrical service
through new above ground and underground 100 Amp 480V feeders. A new 100 Amp 480V AC
disconnect would be installed in the main electrical room along with a new 100 Amp fuse inside the
existing service switchboard for the new PV system.
Bainbridge Island PV and Battery Storage
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Fire Station #21
Existing Conditions
Site Overview
The site is located near the middle east side of the island and encompasses approximately 150 acres.
The site changes in geography throughout several locations. The site is generally flat. There are existing
trees at the west edge of the property line that were noted, however, they appear to be far enough
back and not tall enough to impact west facing PV modules
Building Overview
The building is a wood framed type V-B construction two story building consisting of approximately
28,000 square feet. The building was constructed in 2017 and is in good condition. The building has a
large west facing sloped roof which is ideal for solar panels.
Structure Overview
Refer to KPFF Structural Summary Exhibit B.1
Electrical Overview
The existing building electrical system is served by Puget Sound Energy (PSE) through three 75kVA pole
mounted transformers. The existing service is rated 1000 Amps 208Y/120V 3 phase 4 wire. The service
consists of a UPGS and meter located on the north exterior wall of the building and a main 1000 Amp
panel located inside the north electrical room. 120/208V power is routed throughout the building from
main panel MDP1. There is a 300kW emergency generator located just outside of the electrical room.
Recommendations and Approach
System Sizing
Based on the estimated 13,000 sq. ft. of west facing roof space, it is estimated that a total of (282)
modules could be placed on the upper and lower west facing roof. Assuming 430 watt panels, this
would equate to a 121.26kWDC system size with an estimated annual production of 128.5MWh. With
an annual consumption of 289.08MWh, this would provide approximately 33% of the buildings power.
Electrical Point of Connection and Required Upgrades for POC
Based on the electrical service voltage of 208V, the arrays would need to be split into two 50kW
inverters with a combined AC output of 280 Amps. The point of connection would need to be line side
given that the 1000 Amp switchboard is limited to 120% or 200 Amps of PV on the load side.
Alternatively, based on a peak demand of 62.32kW, the main breaker could be downsized to 800 Amps
which would allow for up to 400 Amps of PV. A line side connection would require a line side tap and
field UL recertification for the existing switchboard. A 400 Amp breaker would be installed either
external and adjacent to the MDP if line side, or in MDP if load side. The breaker would feed a 400 Amp
non fused disconnect mounted to the outside of the building as there is very little space in the existing
electrical room for new equipment. A 400 Amp combiner panelboard would be required with two 200
Amp breakers to feed each of the 50kW inverters located at the exterior of the building. DC conductors
would head up to the roof mounted arrays from the inverters.
Bainbridge Island PV and Battery Storage
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Woodward Middle School
Existing Conditions
Site Overview
The Woodward Middle School site is located near the middle east side of the island in a R-0.4, OSR 0.4
residential use zone and encompasses approximately 67.5 acres. The buildings are located on a gentle
slope. There are existing trees at the west edge of the property line. These trees will most likely shade
portions of the west facing roof at the north end of the campus buildings. The trees at the south end
appear to be far enough away to have little to no impact to PV modules on the southwest facing roof at
the south end of the campus.
Building Overview
The existing campus was constructed in 1994 with a reroof occurring in 2013. The buildings are wood
frame type V-1HR construction, two story. Building Areas 1 and 2 have southwest and west facing roof
space ideal for PV modules.
Structure Overview
Refer to KPFF Structural Summary Exhibit B.1
Electrical Overview
The existing building electrical system is served by Puget Sound Energy (PSE) through a 3000kVA pad
mounted transformer. The existing service is rated 4000 Amps 480Y/277V 3 phase 4 wire. The service
consists of a 3800 Amp main switchboard “MDP” located inside the main electrical room. From there,
480V feeds are distributed throughout the campus. The Area 1 and 2 building is fed from 2000 Amp
panel DP-1. There is an existing 70kW emergency generator.
Recommendations and Approach
System Sizing
With approximately 23,000 sq. ft.of useable roof space, the south end of the campus is ideal for PV
modules due to orientation and sufficient distance from the tree line. Based on available roof space in
that location, it is estimated that a total of (281) modules could be placed on the upper and lower west
facing roof. Assuming 430 watt panels, this would equate to a 120.83kWDC system size with an
estimated annual production of 132.47MWh. With an annual consumption of 1,640MWh, a 120kW PV
array would produce approximately 8% of the sites power needs.
Electrical Point of Connection and Required Upgrades for POC
The PV system would be tied in at the 2000 Amp distribution panel DP-1 which is located in the main
electrical room. A 150 Amp breaker would be added to DP-1 and serve as the load side connection
overcurrent device. From there a 200 Amp disconnect would be provided in the electrical room
adjacent to the main service switchboard. A 150 Amp feeder would be run from that location to a
100kW inverter located on the exterior of the building. DC conductors would be run from the inverter
up to the roof PV modules. New PV modules would be installed on the upper and lower southwest and
northwest facing roofs.
Bainbridge Island PV and Battery Storage
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Conclusion and Recommendations
Electrical Modifications Required
As part of the decision criteria, electrical modifications must be considered as they have a direct impact
on the amount of budget that remains for the PV modules and inverters. Upon completion of site
investigation, the sites have been ranked by complexity of tying the new PV system into the existing site
electrical distribution and rough order of magnitude costs.
Location Work Required Disconnect within
sight of Service
Disconnect
Opinion of
Estimated
Cost
WSF Terminal OHL Load side connection, new 200 Amp
breaker, 200 Amp disconnect, trenching,
new combiner panel, refeed of existing
PV
Yes $50,000
Fire Station #21 Line or load side connection, new 400
Amp breaker or replacement of main
breaker, 400 Amp disconnect, 400 Amp
combiner panel
No $50,000
WSF Eagle Harbor
Maintenance
Load side Connection, new 150 Amp
breaker, 200 Amp disconnect, trenching,
feeder
No $30,000
B.I. Recreation Center Load side connection, new 100 Amp
breaker, 100 Amp disconnect, trenching,
feeder
Yes $25,000
Woodward Middle
School
Load side connection, new 150 Amp
breaker, 200 Amp disconnect
Yes $10,000
Bainbridge Island PV and Battery Storage
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Summary of Sites and Recommended Site for the 120kW PV system
Based on the various factors considered and as shown in the post-site visit decision matrix (Figure 2), it
is recommended that the Woodward Middle School site be selected for the 120kW PV system.
Woodward Middle School
This site had the largest amount of available roof space for PV modules. The orientation of the
southwest roof is ideal for maximum solar collection. The buildings are aged, however, the roof has
been replaced and is anticipated to have at least 20 years more life expectancy. Based on discussions
with the Director of Facilities & Operations, the school is expected to remain in operation of at least 30
more years. The service size and voltage along with location in proximity to the proposed PV array
requires minimal changes to the existing electrical distribution for interconnection. This site scored the
highest among all other sites. The power use is the second highest among all sites. It is recommended
that if this site is ultimately selected for a PV array, the energy cost savings be used for further energy
improvements to maximize the impact of the on-site renewable energy.
Fire Station #21
The west facing sloped roof which is fairly new and solar ready made this a prime candidate for the new
PV system. However, because the building electrical service is 208V rather than 480V, the electrical
connection is required to be twice the size in amps of other 480V sites. Additionally, the solar ready
zone shown on record drawings is in the wrong area of the roof. Due to significant electrical
modifications required for interconnecting a PV array to the electrical service, this site did not score the
highest.
WSF Terminal OHL
Due to the limitations of available roof space and the extent of electrical modifications required for
interconnecting an additional PV array, this site is not a top candidate for a 120kW PV system. The
current PV system AC disconnect location should be reviewed for compliance with local AHJ
requirements. At a minimum, a plaque should be provided at the main service disconnect showing the
location of the PV disconnect as per NEC 705.10.
WSF Eagle Harbor Maintenance
This site is a good candidate for PV, however, the age of the existing building and roof is a concern. No
original building drawings could be located. The age of the roof and unknown original design loads,
existing connection details, wood species, etc. makes this roof higher risk than other sites.
B.I. Recreation Center
Due to the limitations of available roof space, age of the existing roof, and the extent of electrical
modifications required for interconnecting a PV array to the electrical service located at a different
building, this site is not a top candidate for a 120kW PV system.
FIGURE 1 - Bainbridge Solar PV Decision Matrix - Initial Application
Weights 40% 40% 10% 10% 100%
Scoring
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Score Score representation
Woodward Middle School 9125 Sportsman Club Rd NE 15,109 SF 23,000 2013 1,500,000 23.0 30.0 1.0 19.0 23.2 ||||||||||||||||||||||||||||||||||||||||||||||
Fire Station 21 8895 Madison Ave NE 13,253 SF 13,000 2018 289,080 13.0 30.0 30.0 24.0 22.6 |||||||||||||||||||||||||||||||||||||||||||||
Eagle Harbor Maintenance Facility
Main Building
497 Harborview Drive SE,
Bainbridge Island, WA 98110 10,000 SF 13,365 2013 1,900,000 13.4 30.0 1.0 19.0 19.3 ||||||||||||||||||||||||||||||||||||||
Bainbridge Island Ferry Terminal --
Overhead Loading Structure
270 Olympic Drive SE,
Bainbridge Island, WA 98110 9,200 SF 3,000 2023 427,050 3.0 30.0 30.0 29.0 19.1 ||||||||||||||||||||||||||||||||||||||
Bainbridge Island Recreation
Center 11700 NE Meadowmeer Circle 4,500 SF 7,800 2000 427,000 7.8 30.0 1.0 6.0 15.8 |||||||||||||||||||||||||||||||
Fire Station 22 7934 Bucklin Hill Rd 3,289 SF 3,000 2019 140,000 3.0 20.8 1.0 25.0 12.0 ||||||||||||||||||||||||
Fire Station 23 12985 Phelps Rd NE 1,995 SF 2,000 1995 129,000 2.0 19.2 1.0 1.0 8.6 |||||||||||||||||
Criteria Explaination
Sufficient Load: 3.7 hrs/day x 120,000 watts + 20% = 202,000 kw per year required. Points given as percent of total load required with 30 maximum
Designed for Solar Ready: 30 Points for Yes, 1 point for No
Age of Roof: Points reduceded as age of roof increases over 1 year.
Size of Roof: Need 12,000 sq ft for PV modules without consideration existing roof obstructions and clearances. Provided 1 point for each 1,000 sq ft of roof South or West facing. Points reduced if
shading is present. (Google Earth image is dated 2013, so weight has been reduced.)
FIGURE 2 - Bainbridge Solar PV Decision Matrix - Post Site Visits
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Woodward Middle School 9125 Sportsman Club Rd NE 15,109 SF 17,000 2013 1,500,000 17.0 24.0 30.0 1.0 19.0 15.0 18.0 |||||||||||||||||||||||||||||||||||
Fire Station 21 8895 Madison Ave NE 13,253 SF 13,000 2018 289,080 13.0 0.0 30.0 30.0 24.0 25.0 17.8 |||||||||||||||||||||||||||||||||||
Bainbridge Island Ferry Terminal --
Overhead Loading Structure
270 Olympic Drive SE,
Bainbridge Island, WA 98110 9,200 SF 3,000 2023 427,050 3.0 0.0 30.0 30.0 29.0 30.0 15.8 |||||||||||||||||||||||||||||||
Eagle Harbor Maintenance Facility
Main Building
497 Harborview Drive SE,
Bainbridge Island, WA 98110 10,000 SF 13,365 2013 1,900,000 13.4 12.0 30.0 1.0 19.0 10.0 14.0 |||||||||||||||||||||||||||
Bainbridge Island Recreation
Center 11700 NE Meadowmeer Circle 4,500 SF 7,800 2000 427,000 7.8 15.0 30.0 1.0 6.0 10.0 11.6 |||||||||||||||||||||||
Criteria Explaination
Sufficient Load: 3.7 hrs/day x 120,000 watts + 20% = 202,000 kw per year required. Points given as percent of total load required with 30 maximum
Designed for Solar Ready: 30 Points for Yes, 1 point for No
Age of Roof: Points reduceded as age of roof increases over 1 year.
Electrical Modifications: Higher points for lower cost of connecting to existing electrical system
Structural Impact: Higher points for lower potential structural impacts and upgrades
Size of Roof: Need 12,000 sq ft for PV modules without consideration existing roof obstructions and clearances. Provided 1 point for each 1,000 sq ft of roof South or West facing. Points reduced if shading is
present. (Google Earth image is dated 2013, so weight has been reduced.)
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DESIGNER REPORT Page 1 of 5 Site ID: 598098093323080
BAINBRIDGE W SF EAGLE H ARBOR M AINTENANCE
H arborvie w Drive South e as t 497, Bainbridge Is land, W as h ington, 98110, Unite d State s M ar 17, 2024
SYSTEM OVERVIEW 288 PV m odules 1 Inve rte r 144 Optim ize rs
SIM ULATION RESULTS
Ins talled DC Pow e r
123.84 k Wp
M ax Ach ie ve d AC Pow e r
99.90 k W
Annual Ene rgy Production
136.62 MWh
CO
CO2 Em is s ion Save d (Annually)
96.59 t
**
Eq uivalent Tre e s Plante d (Annually)
4,436
SYSTEM PRODUCTION
Total Production - 100 %
136.62 MWh
Se lf-cons um ption - 100 %
136.62 MWh
Export - 0 %
0.00 W h
136.62
MWh
CONSUM PTION
Total Cons um ption - 100 %
1.90 GW h
Se lf-cons um ption - 7 %
136.62 MW h
Im port - 9 3 %
1.76 GW h
1.90
GWh
DESIGNER REPORT Page 1 of 5 Site ID: 598098093323080
BAINBRIDGE W SF EAGLE H ARBOR M AINTENANCE
H arborvie w Drive South e as t 497, Bainbridge Is land, W as h ington, 98110, Unite d State s M ar 17, 2024
SYSTEM OVERVIEW 288 PV m odules 1 Inve rte r 144 Optim ize rs
SIM ULATION RESULTS
Ins talled DC Pow e r
123.84 k Wp
M ax Ach ie ve d AC Pow e r
99.90 k W
Annual Ene rgy Production
136.62 MWh
CO
CO2 Em is s ion Save d (Annually)
96.59 t
**
Eq uivalent Tre e s Plante d (Annually)
4,436
SYSTEM PRODUCTION
Total Production - 100 %
136.62 MWh
Se lf-cons um ption - 100 %
136.62 MWh
Export - 0 %
0.00 W h
136.62
MWh
CONSUM PTION
Total Cons um ption - 100 %
1.90 GW h
Se lf-cons um ption - 7 %
136.62 MW h
Im port - 9 3 %
1.76 GW h
1.90
GWh
DESIGNER REPORT Page 1 of 5 Site ID: 6348368230552017
BAINBRIDGE FIRE STATION #21
M adison Ave nue North 8895, Bainbridge Island, W ash ington, 98110, Unite d State s Mar 17, 2024
SYSTEM OVERVIEW 282 PV m odules 2 Inve rte rs 141 Optim ize rs
SIM ULATION RESULTS
Ins talled DC Pow e r
121.26 k Wp
M ax Ach ie ve d AC Pow e r
100.00 k W
Annual Ene rgy Production
128.50 MWh
CO
CO2 Em is s ion Save d (Annually)
90.85 t
**
Eq uivalent Tre e s Plante d (Annually)
4,173
SYSTEM PRODUCTION
Total Production - 100 %
128.50 MWh
Se lf-cons um ption - 75 %
96.75 MWh
Export - 25 %
31.75 MWh
128.50
MW h
CONSUM PTION
Total Cons um ption - 100 %
289.08 MW h
Se lf-cons um ption - 33 %
96.75 MWh
Im port - 67 %
192.33 MW h
289.08
MWh
DESIGNER REPORT Page 1 of 5 Site ID: 6348368230552017
BAINBRIDGE FIRE STATION #21
M adison Ave nue North 8895, Bainbridge Island, W ash ington, 98110, Unite d State s Mar 17, 2024
SYSTEM OVERVIEW 282 PV m odules 2 Inve rte rs 141 Optim ize rs
SIM ULATION RESULTS
Ins talled DC Pow e r
121.26 k Wp
M ax Ach ie ve d AC Pow e r
100.00 k W
Annual Ene rgy Production
128.50 MWh
CO
CO2 Em is s ion Save d (Annually)
90.85 t
**
Eq uivalent Tre e s Plante d (Annually)
4,173
SYSTEM PRODUCTION
Total Production - 100 %
128.50 MWh
Se lf-cons um ption - 75 %
96.75 MWh
Export - 25 %
31.75 MWh
128.50
MW h
CONSUM PTION
Total Cons um ption - 100 %
289.08 MW h
Se lf-cons um ption - 33 %
96.75 MWh
Im port - 67 %
192.33 MW h
289.08
MWh
Engineer's Opinion of Estimated Cost
Bainbridge Island 120kW PV System
City of Bainbridge Island
4/8/2024
Woodward Middle School
MATERIAL QTY UNIT COST/MATL LABOR/MAN IN PLACE
UNIT COST UNIT HOURS COST
ITEM #1 ELECTRICAL SERVICE AND INFRASTRUCTURE
150 AMP LOAD SIDE BREAKER 1 EA 1,500.00$ 1,500.00$ 4.00 4.00 2,138.00$
200 AMP FUSED DISCO, HD, NEMA 3R, 480V 3PH 1 EA 2,500.00$ 2,500.00$ 4.00 4.00 3,230.00$
INVERTER FEEDER 4#1/0 1#6GRD - 2"C 50 FT 43.34$ 2,167.00$ 0.32 16.17 4,387.86$
TOTAL COST THIS SECTION 9,755.86$
ITEM #2 PV SYSTEMS
SOLAR MODULE - 430 WATT Monocrystalline 281 EA 400.00$ 112,400.00$ 1.00 281.00 157,865.80$
POWER OPTIMIZER 141 EA 156.00$ 21,996.00$ 1.00 141.00 41,644.63$
INVERTER - 100kW 1 EA 32,500.00$ 32,500.00$ 20.00 20.00 37,990.00$
PW WIRING 1 LOT 24,000.00$ 24,000.00$ 140.00 140.00 43,708.00$
RACKING SYSTEM 1 LOT 30,000.00$ 30,000.00$ 120.00 120.00 47,760.00$
TOTAL COST THIS SECTION 328,968.43$
SUB TOTALS >>>>>>>>>>>>>>>>> 227,063.00$ 726.17
SALES TAX 9.2% >>>>>>>>>>>>>>>>>20,889.80$
LABOR HOURLY RATE >>>>>>>>>>>>>>>>>125.00$
TOTALS >>>>>>>>>>>>>>>>>247,952.80$ 90,771.50$
TOTAL MATERIAL & LABOR 338,724.30$
GENERAL MARKUPS
DESIGN CONTINGENCY 10.00% - 33,872.43$
ESCALATION TO FALL 2024 4.50% - 16,766.85$
GENERAL CONDITIONS/REQUIREMENTS 35.00% - 136,277.25$
CONTRACTOR OVERHEAD AND PROFIT 20.00% - 105,128.17$
BONDS & INSURANCE 3.50% - 22,076.91$
TOTAL CONSTRUCTION COST 652,845.91$
DISCLAIMER:
This Cost Estimate has been prepared in accordance with generally accepted professional practices for the
intended project use. There is no guarantee this estimate will not vary from actual construction costs.
Design West Engineering shall be not be held accountable for reliance on this cost estimated for financial purposes.