HomeMy WebLinkAboutSEA-AEE-Skagway K-12 School 2012-EE
Skagway K-12 School
City of Skagway
Funded by:
Final Report
February 2012
Prepared by:
Energy Audit
Table of Contents
Section 1: Executive Summary 2
Section 2: Introduction 6
Section 3: Energy Efficiency Measures 8
Section 4: Description of Systems 14
Section 5: Methodology 17
Appendix A: Energy and Life Cycle Cost Analysis 20
Appendix B: Energy and Utility Data 26
Appendix C: Equipment Data 32
Appendix D: Abbreviations 35
Audit Team
The energy audit is performed by Alaska Energy Engineering LLC of Juneau, Alaska. The audit team
consists of:
Jim Rehfeldt, P.E., Energy Engineer
Jack Christiansen, Energy Consultant
Brad Campbell, Energy Auditor
Loras O’Toole P.E., Mechanical Engineer
Will Van Dyken P.E., Electrical Engineer
Curt Smit, P.E., Mechanical Engineer
Philip Iverson, Construction Estimator
Karla Hart, Technical Publications Specialist
Jill Carlile, Data Analyst
Grayson Carlile, Energy Modeler
Skagway K-12 School 1 Energy Audit (February 2012)
Section 1
Executive Summary
An energy audit of the Skagway K-12 School was performed by Alaska Energy Engineering LLC.
The investment grade audit was funded by Alaska Housing Finance Corporation (AHFC) to identify
opportunities to improve the energy performance of public buildings throughout Alaska.
Skagway School is a 45,518 square foot building that contains commons, classrooms, offices, a music
room, a gym, a kitchen, a library, a shop, storage, and mechanical support spaces.
Building Assessment
The following summarizes our assessment of the building.
Envelope
The envelope of the Skagway School appears to be well preserved and is providing good service. The
shell package is both attractive and efficient in design and construction. Building envelope issues
include:
Complex Framing: The design of the attic mechanical spaces required significant attention to
detail during the construction phase to create a contiguous vapor barrier around the
conditioned spaces. This is because the vapor barrier on the exterior walls and perimeter
ceiling spaces must transition between all of the ceiling joists to the inside of the attic walls
and maintain a seal while doing so. The large metal trusses and wood beams in the attic
mechanical spaces that penetrate the vapor barrier surface compound the difficulty of this
exercise. At the contact point of the drywall and the metal trusses or wooden beams, air
infiltration could be felt when the AHU’s were operated and the attic space became
negatively pressurized. Air infiltration could be reduced along these intersections with the
application of a spray foam sealant.
Failed Insulation: Approximately 40 square feet of insulation have fallen down in the ceiling
space above Room 316.
Arctic Entrances: Double door entries are not installed at the ends of the hallways. As a result
the main classroom hallways have been difficult to heat during periods of cold weather.
School operations have had to be modified to limit the use of these hallway doors as
‘emergency exits’ only in an attempt to retain hallway heat. Double door entries should be
included on all new construction.
Exterior Doors: Exterior doors are not thermally broken. Future exterior door replacement
selection should include this feature. Weather stripping on several doors is in poor condition
and should be replaced.
Skagway K-12 School 2 Energy Audit (February 2012)
Heating System
The school spaces are heated by two fuel oil boilers that provide heat to seven air handling unit
systems, unit heaters, and perimeter hydronic systems.
In addition to meeting the heating demands of the school, the boilers have adequate capacity to supply
all domestic hot water needs. However, a 250-gallon oil-fired hot water heater is currently utilized for
this purpose. Oil-fired hot water heaters have cycling and standby losses and require maintenance,
hence operational and maintenance efficiencies are reduced. Staff recognizes that the system is
oversized and has isolated and shut down the original 500-gallon unit. The 250-gallon unit presently
supplies the entire school. The original water heaters are sized to carry all of the domestic hot water
needs, including an excessive anticipated shower water demand. Staff observed that the showers have
only been used twice during this school year. This is a common defect in school domestic hot water
system sizing; the hot water systems and subsequent boiler sizing are oversized based on a level of
shower water consumption that never materializes. Because the boilers are operating the entire school
year, both domestic hot water heaters could be removed and replaced with two 120-gallon indirect hot
water heaters. In addition, because the boilers are oversized to meet an unnecessarily high hot water
heating demand and they are now 28 years old, replacing one unit with a modern and more efficient
properly sized unit should be considered.
The remainder of the fuel oil boiler heating system appears to be in good condition; however fairly
simple improvements can be made to improve its effectiveness and efficiency. These are outlined in
Section 3, Energy Efficiency Measures.
Ventilation Systems
The building has seven air handling unit systems, three of which are not in use. These include AHU-3
for the shop, AHU-6 for the locker rooms and AHU-7 for the music room. To reduce energy
consumption, the remaining units (with the exception of AHU-5 for the gym) have schedules that turn
off the units when the school is not occupied.
The ventilation to the classrooms has been reduced by closing the variable air volume boxes serving
each classroom. While this measure and the reduction of AHU run-hours has been helpful from an
operational cost perspective, air quality is reduced due to the lack of outside air exchanged in the
school. The metric for air quality and the need for exchanging new air is the CO2 level within a space.
Guidelines suggest that CO2 levels not exceed the ASHRAE action level of 1000 ppm.
The CO2 levels were checked throughout the building and the following levels were found:
Hallways, gym, lockers, multipurpose room, and offices 500-600 ppm
Individual classes with 5-10 students 1000-1100 ppm
Room 303 at the end of the hallway 1130 ppm
We recommend that AHU-1 and AHU-2 run times be increased and that air flow be reestablished to
the classrooms to provide higher quality air to the high school and elementary wings of the building.
While the CO2 levels of the locker rooms were acceptable, we also recommend that AHU-6 and EF-1
be operated for at least half an hour per day to exchange the air in those spaces to help reduce
moisture levels and the subsequent threat of mold/mildew issues.
Skagway K-12 School 3 Energy Audit (February 2012)
Lighting
Interior lighting consists primarily of T12 and T8 fluorescent fixtures throughout the classrooms,
commons, and office spaces. Staff has converted approximately 50% of the T12 fixtures to more
efficient T8 lamps and expects to complete the conversion of all fixtures to T8’s by next summer. All
calculations of potential energy savings have been made using the more efficient T8 fixtures.
Metal halide lighting is used in the library and the gym. Existing gym lighting utilizes 28 pendant-
mounted metal halide bulbs to light the space for approximately 60 hours per week to support school-
hour class activities and after-school sports and community events. It is estimated that lighting hours
could be reduced to 40 hours/week with the selection of a lamp that can start instantaneously because
staff currently do not shut off metal halide fixtures once energized so they don’t have to wait 10-15
minutes for restart. Only 50% of the lighting in the library is typically utilized because the 250-watt
metal halide fixtures over light the space. Staff would like to replace the library metal halide lighting
with a more efficient fixture that still provides the ability to be dimmed when necessary.
Exterior lighting primarily consists of metal halide lighting. Only 4 of the 24 outdoor architectural
wall lights are utilized, and only for evenings with special events. Because lighting operational hours
are controlled by staff, operational costs for lighting with existing infrastructure are kept to a
minimum. Replacement of existing exterior metal halide fixtures with more efficient units is a
solution for further reducing operational costs.
Summary
It was the assessment of the energy audit team that the majority of the building energy losses are due
to the need to optimize air handling unit schedules and operations, the lack of occupancy sensor
control of restroom lighting and fans, and the need to improve lighting efficiency in the gym space.
Energy Efficiency Measures (EEMs)
All buildings have opportunities to improve their energy efficiency. The energy audit revealed several
opportunities in which an efficiency investment will result in a net reduction in long-term operating
costs.
Behavioral and Operational EEMs
The following EEMs require behavioral and operational changes in the building use. The savings are
not readily quantifiable but these EEMs are highly recommended as low-cost opportunities that are a
standard of high performance buildings.
EEM-1: Replace Broken Window
EEM-2: Install Indirect Hot Water Heaters
EEM-3: Clear Access to Perimeter Heaters
EEM-4: Install Pipe and Valve Insulation
Skagway K-12 School 4 Energy Audit (February 2012)
High and Medium Priority EEMs
The following EEMs are recommended for investment. They are ranked by life cycle savings to
investment ratio (SIR). This ranking method places a priority on low cost EEMs which can be
immediately funded, generating energy savings to fund higher cost EEMs in the following years.
Negative values, in parenthesis, represent savings.
25-Year Life Cycle Cost Analysis
Investment Operating Energy Total SIR
High Priority
EEM-5: Isolate Lag Boiler $500 $2,000 ($39,700) ($37,200) 75.4
EEM-6: Electrical Room Heat Recovery $1,800 $0 ($23,100) ($21,300) 12.8
EEM-7: Replace Aerators $800 $0 ($6,400) ($5,600) 8.0
EEM-8: Perform Boiler Combustion Test $700 $12,300 ($15,100) ($2,100) 4.0
EEM-9: Optimize HVAC Systems $111,000 $5,100 ($410,400) ($294,300) 3.7
Medium Priority
EEM-10: Upgrade Motors $6,000 $0 ($13,300) ($7,300) 2.2
EEM-11: Install Occupancy Sensors $16,200 ($600) ($35,600) ($20,000) 2.2
EEM-12: Upgrade Gym Lighting $29,800 ($2,100) ($59,600) ($31,900) 2.1
EEM-13: Boiler Room Heat Recovery $107,500 $4,300 ($187,000) ($75,200) 1.7
Totals* $274,300 $21,000 ($790,200) ($494,900) 2.8
*The analysis is based on each EEM being independent of the others. While it is likely that some
EEMs are interrelated, an isolated analysis is used to demonstrate the economics because the audit
team is not able to predict which EEMs an Owner may choose to implement. If several EEMs are
implemented, the resulting energy savings is likely to differ from the sum of each EEM projection.
Summary
The energy audit revealed numerous opportunities for improving the energy performance of the
building. We recommend that the behavioral and high priority EEMs be implemented now to generate
energy savings from which to fund the medium priority EEMs.
Another avenue to consider is to borrow money from AHFCs revolving loan fund for public
buildings. AHFC will loan money for energy improvements under terms that allow for paying back
the money from the energy savings. More information on this option can be found online at
http://www.ahfc.us/loans/akeerlf_loan.cfm.
Skagway K-12 School 5 Energy Audit (February 2012)
Section 2
Introduction
This report presents the findings of an energy audit of the Skagway K-12 School located in Skagway,
Alaska. The purpose of this investment grade energy audit is to evaluate the infrastructure and its
subsequent energy performance to identify applicable energy efficiencies measures (EEMs).
The energy audit report contains the following sections:
Introduction: Building use and energy consumption.
Energy Efficiency Measures: Priority ranking of the EEMs with a description, energy
analysis, and life cycle cost analysis.
Description of Systems: Background description of the building energy systems.
Methodology: Basis for how construction and maintenance cost estimates are derived and the
economic and energy factors used for the analysis.
BUILDING USE
Skagway School is a 45,518 square foot building that contains commons, classrooms, offices, a music
room, a gym, a kitchen, a library, a shop, storage, and mechanical support spaces. The school is
operated by 15 staff and attended by 58 students. The facility schedule is:
Teachers: 8:00 am – 4:00 pm (M-F)
Students: 8:15 am – 3:15 pm (M-F)
Gym Average of three hours per day between 8:00 am – 4:00 pm (M-F)
4:00 pm - 6:00 pm (M-F) Sports Practice
Building History
1983 – Original Construction
1984 – School Addition
Skagway K-12 School 6 Energy Audit (February 2012)
Energy Consumption
The building energy sources include an electric service and a fuel oil tank. Fuel oil is used for the
majority of the heating loads and domestic hot water while electricity serves all other loads. The
following table shows annual energy use and cost.
Annual Energy Consumption and Cost
Source Consumption Cost Energy, MMBtu
Electricity 234,000 kWh $50,200 798 32%
Fuel Oil 12,500 Gallons $42,800 1,698 68%
Totals - $93,000 2,496 100%
Electricity
This chart shows electrical energy use
from 2008 to 2011. The effective cost—
energy costs plus demand charges—is
21.4¢ per kWh.
Fuel Oil
This chart shows heating energy use from
2008 to 2011. The chart compares annual
use with the heating degree days which is a
measurement of the demand for energy to
heat a building. A year with a higher
number of degree days reflects colder
outside temperatures and a higher heating
requirement.
Cost of Heat Comparison
This chart shows a comparison of the current cost of fuel oil heat and
electric heat. The comparison is based on a fuel oil conversion
efficiency of 70% and electric boiler conversion efficiency of 95%.
Fuel oil heat is currently less expensive than electric heat.
Skagway K-12 School 7 Energy Audit (February 2012)
Section 3
Energy Efficiency Measures
The following energy efficiency measures (EEMs) were identified during the energy audit. The
EEMs are priority ranked and, where applicable, subjected to energy and life cycle cost analysis.
Appendix A contains the energy and life cycle cost analysis spreadsheets.
The EEMs are grouped into the following prioritized categories:
Behavioral or Operational: EEMs that require minimal capital investment but require
operational or behavioral changes. The EEMs provide a life cycle savings but an analysis is
not performed because the guaranteed energy savings is difficult quantify.
High Priority: EEMs that require a small capital investment and offer a life cycle savings.
Also included in this category are higher cost EEMs that offer significant life cycle savings.
Medium Priority: EEMs that require a significant capital investment to provide a life cycle
savings. Many medium priority EEMs provide a high life cycle savings and offer substantial
incentive to increase investment in building energy efficiency.
BEHAVIORAL OR OPERATIONAL
The following EEMs are recommended for implementation. They require behavioral or operational
changes that can occur with minimal investment to achieve immediate savings. These EEMs are not
easily quantified by analysis because they cannot be accurately predicted. They are recommended
because they offer a life cycle savings, represent good practice, and are accepted features of high
performance buildings.
EEM-1: Replace Broken Window
Purpose: A window on the west end of the elementary wing has a hole in the outer pane from a BB
gun. Energy will be saved if broken window is repaired.
Scope: Repair broken window.
EEM-2: Install Indirect Hot Water Heaters
Purpose: The boilers have adequate capacity to heat the building and the domestic hot water.
However, there are two oil-fired hot water heaters, of which only the smaller 250 gallon
unit is in service. The direct heaters have higher heat loss and maintenance requirements
than an indirect hot water heater. We recommend that when the oil-fired units reach the
end of their service life they are replaced with two indirect hot water heaters.
Scope: When the oil-fired hot water heaters fail, replace them with indirect hot water heaters
connected to the hydronic heating system.
Skagway K-12 School 8 Energy Audit (February 2012)
EEM-3: Clear Access to Perimeter Heaters
Purpose: In some of the school rooms the furniture and shelving units are pushed up against the
perimeter heaters. For the perimeter heating units to operate as effectively and efficiently
as possible, they must have a clear path for air flow above and below them. In the stage
room where bookshelves were blocking over half of the perimeter heaters, the staff
member in the room needed to turn up the thermostat in the space during class hours.
Energy will be saved if staff keeps access to the perimeter heaters open.
Scope: Educate staff of the importance to not block air flow to the base or top of the perimeter
heating units and verify clear access on a routine basis.
EEM-4: Install Pipe and Valve Insulation
Purpose: Approximately 50 square feet of piping and valves are uninsulated in the boiler room,
including the boiler expansion tank and aerator. Energy will be saved if these sections of
piping and distribution components are optimally insulated.
Scope: Install insulation on piping and distribution components.
HIGH PRIORITY
The following EEMs are recommended for implementation because they are low cost measures that
have a high savings to investment ratio. The EEMs are listed from highest to lowest priority. Negative
values, in parenthesis, represent savings.
EEM-5: Isolate Lag Boiler
Purpose: During periods when the outside temperature is warm enough that only one boiler needs
to be operated, circulating hot water through an isolated boiler in a dual boiler system can
result in a 3% efficiency loss of the operable boiler due to the isolated boiler acting as a
heat sink. Energy will be saved if only a single boiler is on line when temperatures
permit.
Scope: Shut down and isolate the lag boiler when only a single boiler is needed to support
building operations.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$120 ($1,400) ($1,280) $500 $2,000 ($39,700) ($37,200) 75.4
EEM-6: Electrical Room Heat Recovery
Purpose: Heat is generated by equipment operating in the electrical room. This heat is removed
with an exhaust fan. Energy will be saved if this generated heat is returned within the
shell of the building.
Scope: Re-route exhaust air ducting to return electrical room heat to the building.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($810) ($810) $1,800 $0 ($23,100) ($21,300) 12.8
Skagway K-12 School 9 Energy Audit (February 2012)
EEM-7: Replace Aerators
Purpose: Energy and water will be saved by replacing the lavatory aerators with low-flow models.
Scope: Replace aerators on lavatories with water-conserving fixtures.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($250) ($250) $800 $0 ($6,400) ($5,600) 8.0
EEM-8: Perform a Boiler Combustion Test
Purpose: Operating the boiler with an optimum amount of excess air will improve combustion
efficiency. Annual cleaning followed by a combustion test is recommended.
Scope: Annually clean and perform a combustion test on the boiler.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$720 ($530) $190 $700 $12,300 ($15,100) ($2,100) 4.0
Skagway K-12 School 10 Energy Audit (February 2012)
EEM-9: Optimize HVAC Systems
Purpose: The building utilizes constant volume heating and ventilation system units to provide
conditioned air to interior spaces during the normal operational schedule, after school
hours for activities, and as needed on weekends. Under most conditions the space
occupancy throughout the majority of these operational hours is less than the design
occupancy. This results in an unnecessarily high fuel and electric demand to support
school operations. Energy will be saved if modifications are made to the respective air
handling systems to reduce air flow when not needed.
Scope: Perform repairs as follows and recommission all air handling units to perform as a
properly integrated system when completed.
AHU-1 and AHU-2
These systems are currently only operated to heat the corridors during cold weather. This
operating mode does not properly ventilate the classrooms. We recommend operating the
systems whenever the classrooms are occupied and improving their efficiency with the
following:
- Convert controls to DDC.
- Remove corridors from the systems and operate fans with minimum 10% outside air
for ventilation.
- Replace turn vanes with VFD’s to modulate fan speed.
AHU-4 (Cafeteria)
- Modify controls to provide sequential control of mixing dampers and heating coil to
maintain room setpoint with CO2 sensor override of mixing dampers.
AHU-5 (Gym)
- Modify controls to provide sequential control of mixing dampers and heating coil to
maintain room setpoint with CO2 sensor override of mixing dampers.
- Install VFD to modulate air flow with cooling requirements; minimum flow of 50%.
Hydronic Heating System
- Operate one pump during mild weather and two pumps during cold weather.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$300 ($16,290) ($15,990) $111,000 $5,100 ($410,400) ($294,300) 3.7
Skagway K-12 School 11 Energy Audit (February 2012)
MEDIUM PRIORITY
Medium priority EEMs will require planning and a higher level of investment. They are
recommended because they offer a life cycle savings. The EEMs are listed from highest to lowest
priority. Negative values, in parenthesis, represent savings.
EEM-10: Upgrade Motors to Premium Efficiency
Purpose: The equipment inspection identified five motors that can be upgraded with premium
efficiency models to save energy. They are:
- AHU-5 7.5 HP
- CP-1 2 HP
- CP-3 3 HP
- AC-1 2 HP (x2)
Scope: Replace identified motors with premium efficiency motors.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($680) ($680) $6,000 $0 ($13,300) ($7,300) 2.2
EEM-11: Install Occupancy Sensors in Locker Rooms
Purpose: Lighting controls for the gym locker rooms are on a manual switch and frequently remain
on even when the rooms are unoccupied. Energy will be saved if a motion detector is
installed to minimize unnecessary lighting hours. We recommend that a 10-minute delay
time is used on the occupancy sensor.
Lighting and exhaust in the toilet rooms are manually controlled from the wall switch and
frequently remain on even when unoccupied. Energy will be saved if an occupancy
sensor is installed to minimize unnecessary lighting and exhaust fan run hours. We
recommend that a 5-minute delay time is used on the occupancy sensor.
Scope: Install an occupancy sensor in each locker room and toilet room to control lighting and
the exhaust fans.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
($30) ($1,360) ($1,390) $16,200 ($600) ($35,600) ($20,000) 2.2
Skagway K-12 School 12 Energy Audit (February 2012)
EEM-12: Upgrade Gym Lighting
Purpose: The existing gym lighting consists of 28 pendant-mounted metal halide fixtures. Staff
currently keeps the lighting on all day despite variable occupancy so they don’t have to
wait 10-15 minutes for restart. We estimate that lighting hours could be reduced by 20
hours per week by using a lamp that can start instantaneously.
Similar light levels could be achieved with multi-lamp T5 lighting. Energy will be saved
if the 28 metal halide light fixtures are replaced with 6-bulb T5 units.
Scope: Replace metal halide lights with 6-bulb T5 units.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
($120) ($3,030) ($3,150) $29,800 ($2,100) ($59,600) ($31,900) 2.1
EEM-13: Boiler Room Heat Recovery
Purpose: Heat generated by the boilers, equipment, and piping is currently rejected outdoors by
VF-1. Energy will be saved if this generated heat is transferred as beneficial heat within
the building.
Scope: Install an air-to-water heat pump in the boiler room. Distribute the heat via hydronic
piping to a fan coil unit installed in each hallway. Replace VF-1 with a motorized damper
that opens whenever a boiler is firing.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$250 ($5,410) ($5,160) $107,500 $4,300 ($187,000) ($75,200) 1.7
Skagway K-12 School 13 Energy Audit (February 2012)
Section 4
Description of Systems
ENERGY SYSTEMS
This section provides a general description of the building systems. Energy conservation
opportunities are addressed in Section 3, Energy Efficiency Measures.
Building Envelope
R-value
Component Description (inside to outside) Existing Optimal
Exterior Wall 5/8” Gyp. bd, 2”x8” studs 16” o.c., R-30 batt, ½” plywood, siding R-32 R-30
Roof 24” o.c. joists w/ R-38 batt, 5/8” gyp. bd. (2 layers) R-38 R-46
Floor Slab 4” Concrete slab-on-grade R-10 R-10
Foundation 8” concrete w/ 2” perimeter insulation board R-10 R-20
Windows Double pane windows w/ storm window inserts R-3 R-5
Doors Steel doors w/ non-thermally broken frames R-1.5 R-5
Heating System
The building is heated by two fuel oil boilers that provide heat to seven air handling unit systems, unit
heaters, and perimeter hydronic systems. The heating system has the following pumps:
CP-1 supplies heat to AHU’s 1, 2, 3, 6, & 7
CP-2 and CP-3 supply heat to AHU’s 4 & 5 and the baseboard heaters
HWCP-1 is the domestic hot water circulation pump
Skagway K-12 School 14 Energy Audit (February 2012)
Ventilation Systems
Area
Fan
System Description
High School AHU-1 12,000 cfm 10 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan. Unit is
currently serving just the hallway; classroom VAV boxes are disabled.
Elementary Hallway AHU-2 12,000 cfm 10 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan. Unit is
currently serving just the hallway; classroom VAV boxes are disabled.
Shop AHU-3 4,200 cfm 3 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan (not used)
Multi-purpose Room AHU-4 4,300 cfm 3 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan
Gym AHU-5 12,800 cfm 7.5 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan
Locker Rooms AHU-6 3,000 cfm 2 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, heat recovery from EF-1, and
supply fan (not used)
Stage AHU-7 3,900 cfm 2 hp constant volume air handling unit consisting of a
heating coil, mixing box, filter section, and supply fan
Locker Rooms EF-1 3,300 cfm 2 hp constant volume exhaust fan with heat recovery
New Addition Restrooms EF-1a 500 cfm constant volume exhaust fan (not used)
High School Restrooms EF-2 500 cfm constant volume exhaust fan
Janitors Closet EF-4 170 cfm constant volume exhaust fan
Electrical Room EF-5 160 cfm constant volume exhaust fan
Special Education
Restroom
EF-6 145 cfm constant volume exhaust fan
Boiler Room VF-1 5,100 cfm ½ hp constant volume exhaust fan
Domestic Hot Water System
The domestic hot water system consists of a 250-gallon oil-fired hot water heater that is on-line and a
500-gallon oil-fired hot water heater that is disconnected. The original water heaters are sized to carry
the anticipated shower demand, but staff observed that the showers have only been used twice this
school year. Because the boilers are also operating the entire school year, both domestic hot water
heaters could be removed and replaced with two smaller indirect hot water heaters.
Automatic Control System
The building has a DDC system to control the operation of the heating and ventilation systems.
Energy can be saved through further optimization of fan system scheduling combined with a retro-
commissioning of the air handler systems.
Skagway K-12 School 15 Energy Audit (February 2012)
Lighting
Interior lighting consists primarily of T12 and T8 fluorescent fixtures throughout the classrooms,
commons, and office spaces. Staff has completed approximately 50% of the conversion of T12
lighting fixtures to the more efficient T8 models and expects to complete the conversion of all
fixtures to T8’s by next summer. All calculations of potential energy savings have been made using
the more efficient T8 fixtures.
Metal halide lighting is used in the library and the gym. Existing gym lighting utilizes 28 pendant-
mounted metal halide bulbs to light the space for approximately 60 hours per week to support school-
hour class activities and after-school sports and community events. We estimate that lighting hours
can be reduced to 40 hours/week with the selection of a lamp that can start instantaneously—staff
does not currently shut off metal halide fixtures once they are energized so as to avoid a 10-15 minute
wait for restart.
Only 50% of the lighting in the library is typically utilized because 250-watt metal halide fixtures
were installed. Staff would like to replace the library metal halide lighting with a more efficient
fixture that still provides the ability to be dimmed when necessary.
Exterior lighting consists primarily of metal halide lighting. Only four of the 24 outdoor architectural
wall lights are utilized, and only for evenings with special events. Because lighting operational hours
are controlled by staff, operational costs for lighting with existing infrastructure are kept to a
minimum. Replacement of existing exterior metal halide fixtures with more efficient units is a
solution for further reducing operational costs.
Electric Equipment
Commercial equipment for food preparation is located in the kitchen and surrounding spaces.
Skagway K-12 School 16 Energy Audit (February 2012)
Section 5
Methodology
Information for the energy audit was gathered through on-site observations, review of construction
documents, and interviews with operation and maintenance personnel. The EEMs are evaluated using
energy and life cycle cost analyses and are priority ranked for implementation.
Energy Efficiency Measures
Energy efficiency measures are identified by evaluating the building’s energy systems and comparing
them to systems in modern, high performance buildings. The process for identifying the EEMs
acknowledges the realities of an existing building that was constructed when energy costs were much
lower. Many of the opportunities used in modern high performance buildings—highly insulated
envelopes, variable capacity mechanical systems, heat pumps, daylighting, lighting controls, etc.—
simply cannot be economically incorporated into an existing building.
The EEMs represent practical measures to improve the energy efficiency of the buildings, taking into
account the realities of limited budgets. If a future major renovation project occurs, additional EEMs
common to high performance buildings should be incorporated.
Life Cycle Cost Analysis
The EEMs are evaluated using life cycle cost analysis which determines if an energy efficiency
investment will provide a savings over a 25-year life. The analysis incorporates construction,
replacement, maintenance, repair, and energy costs to determine the total cost over the life of the
EEM. Future maintenance and energy cash flows are discounted to present worth using escalation
factors for general inflation, energy inflation, and the value of money. The methodology is based on
the National Institute of Standards and Technology (NIST) Handbook 135 – Life Cycle Cost
Analysis.
Life cycle cost analysis is preferred to simple payback for facilities that have long—often perpetual—
service lives. Simple payback, which compares construction cost and present energy cost, is
reasonable for short time periods of 2-4 years, but yields below optimal results over longer periods
because it does not properly account for the time value of money or inflationary effects on operating
budgets. Accounting for energy inflation and the time value of money properly sums the true cost of
facility ownership and seeks to minimize the life cycle cost.
Construction Costs
The cost estimates are derived based on a preliminary understanding of the scope of each EEM as
gathered during the walk-through audit. The construction costs for in-house labor are $60 per hour for
work typically performed by maintenance staff and $110 per hour for contract labor.
The cost estimate assumes the work will be performed as part of a larger renovation or energy
efficiency upgrade project. When implementing EEMs, the cost estimate should be revisited once the
scope and preferred method of performing the work has been determined. It is possible some EEMs
will not provide a life cycle savings when the scope is finalized.
Skagway K-12 School 17 Energy Audit (February 2012)
Maintenance Costs
Maintenance costs are based on in-house or contract labor using historical maintenance efforts and
industry standards. Maintenance costs over the 25-year life of each EEM are included in the life cycle
cost calculation spreadsheets and represent the level of effort to maintain the systems.
Energy Analysis
The energy performance of an EEM is evaluated within the operating parameters of the building. A
comprehensive energy audit would rely on a computer model of the building to integrate building
energy systems and evaluate the energy savings of each EEM. This investment grade audit does not
utilize a computer model, so energy savings are calculated with factors that account for the dynamic
operation of the building. Energy savings and costs are estimated for the 25-year life of the EEM
using appropriate factors for energy inflation.
Prioritization
Each EEM is prioritized based on the life cycle savings to investment ratio (SIR) using the following
formula:
Prioritization Factor = Life Cycle Savings / Capital Costs
This approach factor puts significant weight on the capital cost of an EEM, making lower cost EEMs
more favorable.
Skagway K-12 School 18 Energy Audit (February 2012)
Economic Factors
The following economic factors are significant to the findings.
Nominal Interest Rate: This is the nominal rate of return on an investment without regard to inflation.
The analysis uses a rate of 5%.
Inflation Rate: This is the average inflationary change in prices over time. The analysis uses an
inflation rate of 2%.
Economic Period: The analysis is based on a 25-year economic period with construction beginning in
2012.
Fuel Oil
Fuel oil currently costs $4.03 per gallon for a seasonally adjusted blend of #1 and #2 fuel oil. The
analysis is based on 6% fuel oil inflation which has been the average for the past 20-years.
Electricity
Electricity is supplied by Alaska Power and Telephone. The rate schedule is:
Alaska Power Company Bulk Power A-2
Electricity ($ / kWh ) $0.0946
Cost of Power Adjustment ($ / kWh) $0.0901
Demand ( $ / kW ) $6.95
Customer Charge ( $ / mo ) $84.52
Summary
The following table summarizes the energy and economic factors used in the analysis.
Summary of Economic and Energy Factors
Factor Rate or Cost Factor Rate or Cost
Nominal Discount Rate 5% Electricity $0.214/kwh
General Inflation Rate 2% Electricity Inflation 3%
Fuel Oil Cost (2012) $4.03/gal Fuel Oil Inflation 6%
Skagway K-12 School 19 Energy Audit (February 2012)
Appendix A
Energy and Life Cycle Cost Analysis
Skagway K-12 School 20 Energy Audit (February 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
Basis
Economic
Study Period (years) 25 Nominal Discount Rate 5%General Inflation 2%
Energy
2011 $/gal Fuel Inflation 2012 $/gal
Fuel Oil $4.03 6% $4.27
Electricity $/kWh (2011)$/kW (2011)Inflation $/kWh (2012)$/kW (2012)
w/ Demand Charges $0.185 $6.95 3% $0.191 $7.16
w/o Demand Charges $0.214 -3% $0.220 -
EEM-5: Isolate Lag Boiler
Energy Analysis
Boiler Input MBH Loss %Loss MBH Hours, exist Hours, new kBtu η boiler Gallons
B-1 1,905 0.5% 10 6,480 3,240 -30,857 68%-328
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Establish procedure for isolating boiler 0 1 ea $500 $500
Annual Costs
Isolate boilers annually 1 - 25 2 hrs $60.00 $2,043
Energy Costs
Fuel Oil 1 - 25 -328 gal $4.27 ($39,671)
Net Present Worth ($37,100)
EEM-6: Electrical Room Heat Recovery
Energy Analysis
Fuel Oil
Watts Hours MBH kBtu η boiler Gallons
-600 8,760 -2 -17,933 68% -190
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Exhaust fan ductowrk and exhaust grille 0 1 LS $1,000 $1,000
Estimating contingency 0 15%$150
Overhead & profit 0 30%$345
Design fees 0 10%$150
Project management 0 8%$132
Energy Costs
Fuel Oil 1 - 25 -190 gal $4.27 ($23,056)
Net Present Worth ($21,300)
Skagway K-12 School 21 Energy Audit (February 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
EEM-7: Replace Aerators
Energy Analysis
η boiler 68%
Fixture Existing Proposed Uses/day Days Water,Gals % HW kBTU Gallons
Lavatories 0.3 0.2 200 198 -7,128 80% -3,805 -40
-7,128 -40
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace lavatory aerators 0 23 ea $35 $805
Energy Costs
Water 1 - 25 -7 kgals $10.960 ($1,536)
Fuel Oil 1 - 25 -40 gal $4.27 ($4,891)
Net Present Worth ($5,600)
EEM-8: Perform Boiler Combustion Test
Energy Analysis
Annual Gal % Savings Savings, Gal
12,500 -1.0% -125
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Purchase combustion analyzer 0 1 LS $700 $700
Annual Costs
Clean and combustion test boiler 1 - 25 12 hrs $60.00 $12,259
Energy Costs
Fuel Oil 1 - 25 -125 gal $4.27 ($15,135)
Net Present Worth ($2,200)
Gallons per Use
Skagway K-12 School 22 Energy Audit (February 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
EEM-9: Optimize HVAC Systems
Energy Analysis
Fan Case CFM ΔP η, fan BHP η, motor kW Hours kWh
AHU-1 Existing -12,000 3.00 60%-9 91%-8 1,620 -12,537
Optimized 8,000 2.00 60%4 91%3 1,620 5,572
AHU-2 Existing -12,000 3.00 60%-9 91%-8 1,620 -12,537
Optimized 8,000 2.00 60%4 91%3 1,620 5,572
AHU-5 Existing -12,800 1.60 55%-6 90%-5 1,260 -6,119
Optimized 8,000 1.25 55%3 90%2 1,260 2,988
S-3 Existing -6,000 3.00 55%-5 89%-4 0
Optimized 4,000 2.00 55%2 93%2 0
S-6 Existing -2,400 1.25 50%-1 86%-1 0
Optimized 1,500 0.75 50%0 86%0 0
S-7 Existing -3,600 1.00 50%-1 88%-1 0
Optimized 1,800 0.75 50%0 88%0 0
-15 -17,061
Ventilation SA CFM MAT T,room MBH Hours kBtu η boiler Gallons
AHU-1 Existing -8,000 60 70 -86 1,620 -139,968 68%-1,486
Optimized 8,000 64 70 52 1,620 83,981 68%892
AHU-2 Existing -8,000 60 70 -86 1,620 -139,968 68%-1,486
Optimized 8,000 64 70 52 1,620 83,981 68%892
AHU-4 Existing -4,300 45 70 -116 540 -62,694 68%-666
Optimized 4,300 62 70 37 540 20,062 68%213
AHU-5 Existing -12,800 62 70 -111 1,260 -139,346 68%-1,480
Optimized 8,000 64 70 52 1,260 65,318 68%694
S-7 Existing -3,600 60 70 -39 0 68%0
Optimized 1,800 65 70 10 0 68%0
-228,634 -2,428
Pumping Energy
Pump GPM Head η pump BHP η motor kW Hours kWh
CP-1 -116 30 65% -1.8 89% -1.5 6,480 -9,838
CP-3 -160 40 75% -2.9 89% -2.4 6,480 -15,680
CP-1 116 30 65% 1.8 89% 1.5 5,040 7,651
CP-3 160 40 75% 2.9 89% 2.4 4,320 10,453
-7,413
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Convert AHU-1 and AHU-2 to DDC 0 20 pts $1,500 $30,000
Install VFD for AHU-1 and AHU-2 0 2 LS $7,500 $15,000
AHU-4 and AHU-5: Install CO2 sensor and modify controls 0 2 ea $5,000 $10,000
Install VFD for AHU-5 0 1 LS $7,500 $7,500
Estimating contingency 0 15%$9,375
Overhead & profit 0 30% $21,563
Design fees 0 10%$9,344
Project management 0 8%$8,223
Annual Costs
VFD Maintenance 1 - 25 3 LS $100.00 $5,108
Energy Costs
Electric Energy 1 - 25 -24,473 kWh $0.191 ($91,671)
Electric Demand 1 - 25 -176 kW $7.16 ($24,787)
Fuel Oil 1 - 25 -2,428 gal $4.27 ($293,942)
Net Present Worth ($294,300)
Skagway K-12 School 23 Energy Audit (February 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
EEM-10: Upgrade Motors
Energy Analysis
Equip Number HP ηold ηnew kW Hours kWh
AC-1 1 2 80.8% 86.5% -0.09 2,920 -248
CP-1 1 2 78.5% 89.5% -0.16 6,480 -1,063
CP-2 1 3 81.4% 89.5% -0.18 6,480 -1,175
AHU-5 1 7.5 81.5% 91.7% -0.57 1,260 -719
-1.0 -3,206
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs HP
Replace motor 2 0 3 LS 955 $2,865
Replace motor 3 0 1 LS 970 $970
Replace motor 7.5 0 1 LS 1,690 $1,690
Project management 0 8%$442
Energy Costs
Electric Energy 1 - 25 -3,206 kWh $0.191 ($12,007)
Electric Demand 1 - 25 -9 kW $7.16 ($1,268)
Net Present Worth ($7,300)
EEM-11: Install Occupancy Sensors
Energy Analysis
Location Type # Fixtures Lamp Lamp, watts Fixture Watts Hours, exist Hours, new Savings, kWh
Lockers Surface 22 2T8 64 74 -1,620 540 -1,749
Toilets Surface 16 2T8 64 74 -1,620 720 -1,060
Lamp Replacement
Location # Fixtures Lamp # Lamps Life, hrs Lamps//yr $/lamp $/Replace
Lockers 22 2T8 1 30,000 -0.79 $4 $15
Toilets 16 2T8 1 30,000 -0.48 $4 $15
Exhaust Fans
Unit CFM, ex CFM,new ΔT MBH Hours kBtu η boiler Gallons
EF-1A 500 200 20 -7 1,710 -11,286 68%-120
EF-2 500 200 20 -7 1,710 -11,286 68%-120
-13 -240
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install occupancy sensors 0 6 LS $1,500 $9,000
Estimating contingency 0 15%$1,350
Overhead & profit 0 30%$3,105
Design fees 0 10%$1,346
Project management 0 8%$1,184
Adjust photocell 0 1 LS $200 $200
Annual Costs
Lamp replacements 1 - 25 -1.27 lamps $26.00 ($563)
Energy Costs
Electric Energy 1 - 25 -1,749 kWh $0.191 ($6,550)
Fuel Oil 1 - 25 -240 gal $4.27 ($29,020)
Net Present Worth ($19,900)
Skagway K-12 School 24 Energy Audit (February 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
EEM-12: Upgrade Gym Lighting
Energy Analysis
Type # Fixtures Lamp Lamp, watts Fixture Watts kW Hours, exist Hours, new Savings, kWh
MH -28 MH 400 460 -13 2,400 0 -30,912
T5 28 6T5 310 357 10 0 1,600 15,971
-3 -14,941
Lamp Replacement
# Fixtures Lamp # Lamps Life, hrs Replace/yr $/lamp replace
28 MH -1 20,000 -3.36 $30
28 6T5 6 30,000 1.49 $24
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace 400 watt MH with T5 Fluorescent 0 28 LS $600 $16,800
Estimating contingency 0 15%$2,520
Overhead & profit 0 30%$5,796
Design fees 0 10%$2,512
Project management 0 8%$2,210
Annual Costs
Existing lamp replacement, 400 watt MH 1 - 25 -3.36 replacements $60.00 ($3,433)
New lamp replacement, T5 1 - 25 1.49 replacements $54.00 $1,373
Energy Costs
Electric Energy 1 - 25 -14,941 kWh $0.191 ($55,965)
Electric Demand 1 - 25 -26 kW $7.16 ($3,670)
Net Present Worth ($31,900)
EEM-13: Boiler Room Heat Recovery
Energy Analysis
Heat Recovery
Input, MBH Jacket Loss MBH Hours Loss, kBtu Factor Recovery, kBtu η boiler Gallons
3,810 -1.0% -38 6,480 -246,857 75% -185,143 82%-1,630
Heat Pump Energy
Recovery, kBtu COP kWh HP Heat, kBtu η boiler Gallons
-185,143 3 18,087 61,714 82% -543
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Boiler room heat pump 0 1 LS $15,000 $15,000
Hallway fan coil unit 0 2 LS $6,000 $12,000
Motorized combustion air damper 0 1 LS $3,500 $3,500
Piping between heat pump and fan coil 0 1 LS $22,000 $22,000
Controls 0 1 LS $8,000 $8,000
Estimating contingency 0 15%$9,075
Overhead & profit 0 30% $20,873
Design fees 0 10%$9,045
Project management 0 8%$7,959
Annual Costs
Heat pump maintenance 1 - 25 1 LS $250.00 $4,257
Energy Costs
Electric Energy 1 - 25 18,087 kWh $0.191 $67,751
Electric Demand 1 - 25 60.0 kW $7.16 $8,443
Fuel Oil 1 - 25 -2,174 gal $4.27 ($263,186)
Net Present Worth ($75,300)
Skagway K-12 School 25 Energy Audit (February 2012)
Appendix B
Energy and Utility Data
Skagway K-12 School 26 Energy Audit (February 2012)
Alaska Energy Engineering LLC Billing Data
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
ELECTRIC RATE
Alaska Power Company Bulk Power A-2 Haines
Skagway
Electricity ($ / kWh )$0.0946
Cost of Power Adjustment ($ / kWh)$0.0901
Demand ( $ / kW )$6.95
Customer Charge ( $ / mo )$84.52
Sales Tax ( % )0.0%
ELECTRICAL CONSUMPTION AND DEMAND
kWh kW kWh kW kWh kW kWh kW
Jan 23,400 104 22,400 94 21,200 88 21,600 84 22,150
Feb 28,800 104 25,000 82 25,200 82 25,400 86 26,100
Mar 24,400 98 25,400 88 20,200 80 21,200 86 22,800
Apr 23,400 86 19,600 86 21,000 80 20,600 80 21,150
May 23,400 86 21,800 88 20,600 80 21,600 78 21,850
Jun 10,000 80 11,800 72 12,200 72 13,600 78 11,900
Jul 8,000 32 9,000 36 9,000 34 12,200 50 9,550
Aug 12,200 54 8,400 36 8,400 32 15,000 58 11,000
Sep 21,200 82 19,800 78 19,600 72 19,200 66 19,950
Oct 23,400 88 22,000 82 20,800 76 19,200 44 21,350
Nov 24,400 84 23,200 82 21,600 74 22,400 74 22,900
Dec 23,800 88 23,600 86 23,400 86 22,800 74 23,400
Total 246,400 232,000 223,200 234,800 234,100
Average 20,533 82 19,333 76 18,600 71 19,567 72 19,508
Load Factor 34%35%36%37%75
ELECTRIC BILLING DETAILS
Month Energy Demand Cust & Tax Total Energy Demand Cust & Tax Total % Change
Jan $3,916 $612 $85 $4,612 $3,990 $584 $85 $4,658 1.0%
Feb $4,654 $570 $85 $5,309 $4,691 $598 $85 $5,374 1.2%
Mar $3,731 $556 $85 $4,371 $3,916 $598 $85 $4,598 5.2%
Apr $3,879 $556 $85 $4,519 $3,805 $556 $85 $4,445 -1.6%
May $3,805 $556 $85 $4,445 $3,990 $542 $85 $4,616 3.8%
Jun $2,253 $500 $85 $2,838 $2,512 $542 $85 $3,139 10.6%
Jul $1,662 $236 $85 $1,983 $2,253 $348 $85 $2,685 35.4%
Aug $1,551 $222 $85 $1,858 $2,771 $403 $85 $3,258 75.3%
Sep $3,620 $500 $85 $4,205 $3,546 $459 $85 $4,089 -2.7%
Oct $3,842 $528 $85 $4,454 $3,546 $306 $85 $3,937 -11.6%
Nov $3,990 $514 $85 $4,588 $4,137 $514 $85 $4,736 3.2%
Dec $4,322 $598 $85 $5,004 $4,211 $514 $85 $4,810 -3.9%
Total $ 41,225 $ 5,949 $ 1,014 $ 48,188 $ 43,368 $ 5,963 $ 1,014 $ 50,345 4.5%
Average $ 3,435 $ 496 $ 85 $ 4,016 $ 3,614 $ 497 $ 85 $ 4,195 4.5%
Cost ($/kWh)$0.216 86% 12% 2% $0.214 -0.7%
Month 2008 2009 2010 Average
Electrical costs are based on the current electric rates.
2010 2011
2011
Skagway K-12 School 27 Energy Audit (February 2012)
Alaska Energy Engineering LLC Annual Electric Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Use (kWh)Month of the Year
Electric Use History
2008
2009
2010
2011
0
20
40
60
80
100
120
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Demand (kW)Month of the Year
Electric Demand History
2008
2009
2010
2011
Skagway K-12 School 28 Energy Audit (February 2012)
Alaska Energy Engineering LLC Electric Cost
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School 2011
$ 0
$ 1,000
$ 2,000
$ 3,000
$ 4,000
$ 5,000
$ 6,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Cost (USD)Month of the Year
Electric Cost Breakdown
2010
Electric Use (kWh) Costs
Electric Demand (kW) Costs
Customer Charge and Taxes
0
10
20
30
40
50
60
70
80
90
100
0
5,000
10,000
15,000
20,000
25,000
30,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Electric Demand (kW)Electric Use (kWh)Month of the Year
Electric Use and Demand Comparison
2010
Electric Use
Electric Demand
Skagway K-12 School 29 Energy Audit (February 2012)
Alaska Energy Engineering LLC Annual Fuel Oil Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Skagway K-12 School
Year Fuel Oil Degree Days
2,008 13,990 9,093
2,009 12,986 9,284
2,010 11,700 9,013
2,011 11,300 8,729
5,000
6,000
7,000
8,000
9,000
10,000
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
11,000
12,000
13,000
14,000
15,000
2008 2009 2010 2011 Degree DaysGallons of Fuel OilYear
Annual Fuel Oil Use
Fuel Oil
Degree Days
Skagway K-12 School 30 Energy Audit (February 2012)
Alaska Energy Engineering LLC Billing Data
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Annual Energy Consumption and Cost
Energy Cost $/MMBtu Area ECI EUI
Fuel Oil $4.03 $41.57 45,518 $2.21 55
Electricity $0.214 $66.15
Source Cost
Electricity 234,000 kWh $50,200 800 32%
Fuel Oil 12,500 Gallons $50,400 1,700 68%
Totals $100,600 2,500 100%
Annual Energy Consumption and Cost
Consumption Energy, MMBtu
$0.00
$10.00
$20.00
$30.00
$40.00
$50.00
$60.00
$70.00
Fuel Oil ElectricityCost $ / MMBtuCost of Heat Comparison
Skagway K-12 School 31 Energy Audit (February 2012)
Appendix C
Equipment Data
Skagway K-12 School 32 Energy Audit (February 2012)
MotorHP / Volts / RPM / EfficAHU-1 Central Fan Room High School Hallway Bohn VCS26ALF 12000 CFM 10 HP/ 208 V/ 1745 RPM/ 85.6%AHU-2 Central Fan Room Elementary Hallway Bohn HD26ALF 12000 CFM 10 HP/ 208 V/ 1745 RPM/ 85.6%AHU-3 Central Fan Room Shop Bohn HD08ALF 4200 CFM 3 HP/ 208 V/ 1750 RPM/ 82.5%AHU-4 Central Fan Room Multipurpose Room Bohn VCS08ACF 4300 CFM 3 HP/ 208 V/ 1750 RPM/ 82.5%AHU-5 Central Fan Room Gym Bohn VCS26ALF 12800 CFM 7.5 HP/ 208 V/ 1765 RPM/ 81.5%AHU-6 Central Fan Room Locker Rooms Bohn HD06ALF 3000 CFM 2 HP/ 208 V/ 1725 RPM/ 78.5%AHU-7 Central Fan Room Stage Bohn HD08ALF 3900 CFM 2 HP/ 208 V/ 1760 RPM/ 78.5%EF-1 Gym Fan Room Locker Rooms Trane UI6PT3-FC 3300 CFM 2 HP/ 208 V/ 1725 RPM/ 78.5%EF-1A New Addition Restrooms Penn Zephyr Z12TD 500 CFM 120 V/ 208 WattsEF-2 High School Wing Restrooms Penn Zephyr Z12TD 500 CFM 120 V/ 208 WattsEF-4 Janitor ClosetJanitor Closet ExhaustPenn Zephyr Z8 170 CFM 120 V/ 105 WattsOperates off light switchEF-5 Electrical Room Electrical Room Penn Zephyr Z8 160 CFM 120 V/ 105 WattsEF-6Special Ed. RestroomRestroom Exhaust Penn Zephyr Z8 145 CFM 120 V/ 105 WattsOperates off light switchVF-1 Boiler Room Ventilation Air Greenheck SDP-30-6-15 5100 CFM 1/2 HP/ 120 V/47%B-1 Boiler Room BoilerWeil McLain H-886-S-W 1600 MBHB-2 Boiler Room BoilerWeil McLain H-886-S-W 1600 MBH Lag boiler Not IsolatedCP-1 Boiler Room AHU 1,2,3,6,7 B&G 2AC 6 1/8 BF 116 GPM 2 HP/ 208 V/ 1725 RPM/ 78.5%CP-2 Boiler Room AHU 4, 5, Baseboard B&G 2.5AB 6 5/8 BF 160 GPM 3 HP/ 208 V/ 1730 RPM/ 78.5%CP-3 Boiler Room AHU 4, 5, Baseboard B&G 2.5AB 6 5/8 BF 160 GPM 3 HP/ 208 V/ 1730 RPM/ 78.5%HWH-1 Boiler Room Hot Water Heater Pvi3.8-N-500-A-D 500 Gallon 540 MBHDirect fired fuel oil WH; Not usedHWH-2 Boiler Room Hot Water Heater Pvi27N250A-MXO 250 Gallon 270 MBH / 1/3 HP/60% Direct fired fuel oil WHSkagway K-12 School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make Model
Skagway K-12 School 33 Energy Audit (February 2012)
MotorHP / Volts / RPM / EfficSkagway K-12 School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelHWCP-1 Boiler RoomHot Water Circulation PumpB&G LR-20WR 2 GPM 115 VICV-1 Central Fan Room Central Vacuum Spencer 307740 150 CFM 5 HP/ 208 V/ 3500 RPM/83.3%AC-1 Boiler Room Air Compressor Quincy00020008D00327100 CFM 2 HP/ 208 V/ 1750 RPM/ 78.5% (x2)Freezer Shop Food Storage Heat Craft LET120BK 208 V/ 11.7 pmps/ 2700 WattsEF-7 Shop Paint Fume Exhaust 2 HP/ 208 V/ 1725 RPM/80.8%
Skagway K-12 School 34 Energy Audit (February 2012)
Appendix D
Abbreviations
AHU Air handling unit
BTU British thermal unit
BTUH BTU per hour
CBJ City and Borough of Juneau
CMU Concrete masonry unit
CO2 Carbon dioxide
CUH Cabinet unit heater
DDC Direct digital controls
DHW Domestic hot water
EAD Exhaust air damper
EEM Energy efficiency measure
EF Exhaust fan
Gyp Bd Gypsum board
HVAC Heating, Ventilating, Air-
conditioning
HW Hot water
HWRP Hot water recirculating pump
KVA Kilovolt-amps
kW Kilowatt
kWh Kilowatt-hour
LED Light emitting diode
MBH 1,000 Btu per hour
MMBH 1,000,000 Btu per hour
OAD Outside air damper
PSI Per square inch
PSIG Per square inch gage
RAD Return air damper
RF Return fan
SIR Savings to investment ratio
SF Supply fan
UV Unit ventilator
VAV Variable air volume
VFD Variable frequency drive
Skagway K-12 School 35 Energy Audit (February 2012)