HomeMy WebLinkAboutBSSD-WBB-RSA Stebbins Tukurngailnguq School 2012-EERichard S. Armstrong, PE, LLC
Mechanical/Electrical Engineer
Comprehensive Energy Audit
of
Stebbins Tukurngailnguq K12 School
Stebbins, Alaska
Project # BSSDWBBRSA01
Prepared for:
Bering Strait School District
Contact: Richard Ried, Maintenance Supervisor
Phone: 9076244249
Unalakleet, Alaska
February 17, 2012
Prepared by:
Richard S. Armstrong, PE, LLC
2321 Merrill Field Drive, C$6
Anchorage, AK 99501
and
RSA Engineering, Inc.
2422 Arctic Blvd., Suite 200
Anchorage, AK 99503
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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TABLE OF CONTENTS
1. Report Disclaimers 3
2. Executive Summary 4
3. Audit and Analysis Background 8
4. Acknowledgements 10
5. Building Description & Function 11
6. Historic Energy Consumption 15
7. Energy Efficiency Measures Considered or Recommended 15
8. Interactive Effects of Projects 23
9. Loan Program 24
Appendix A: Photos 25
Appendix B: AkWarm7C Report 40
Appendix C: Building Schedules and Plans 56
Performed by: ___________________________
Adam W. Wilson, PE, CEA
CEA # 1618
RSA Engineering, Inc.
Reviewed by: ___________________________
Richard Armstrong, PE, CEM
CEA #178, CEM # 13557
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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1. REPORT DISCLAIMERS
This audit was performed using American Recovery and Reinvestment Act
(ARRA) funds, managed by the Alaska Housing Finance Corporation
(AHFC).
The information contained in this report, including any attachments, is
intended solely for use by the building owner and the AHFC. This report
contains recommendations that, in the opinion of the auditor, will cause the
owner to realize energy savings over time. All recommendations must be
designed by a registered engineer, licensed in the State of Alaska, in the
appropriate discipline. Lighting recommendations should all be first
reviewed by running a lighting analysis to assure that the recommended
lighting upgrades will comply with State of Alaska Statue as well as IES
recommendations.
Payback periods may well vary from those forecast due to the uncertainty
of the final installed design, configuration, equipment selected, and
installation costs of recommended Energy Efficiency Measures (EEMs), or
the operating schedules and maintenance provided by the owner.
Furthermore, EEMs are typically interactive, so implementation of one
EEM may impact the cost savings from another EEM. Neither the auditor,
Richard S. Armstrong, PE, LLC, AHFC, or others involved in preparation of
this report will accept liability for financial loss due to EEMs that fail to
meet the forecasted payback periods.
This audit meets the criteria of an Investment Grade Audit (IGA) per the
Association of Energy Engineers definition, and is valid for one year. The
life of the IGA may be extended on a case$by$case basis, at the discretion
of the AHFC.
IGSs are the property of the State, and may be incorporated into AkWarm$
C, the Alaska Energy Data Inventory (ARIS), or other state and/or public
information system. AkWarm$C is a building energy modeling software
developed under contract with AHFC.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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Investment Grade Energy Audit
Stebbins Tukurngailnguq K12 School
2. Executive Summary:
The Stebbins Tukurngailnguq K$12 School was constructed in 1992,
using design concepts and construction materials that were common
at that time for school buildings in Western Alaska. It is owned and
operated by the Bering Strait School District (BSSD). Benchmark
energy use data collected for this building is presented in Table 1
below:
Table 1
2009 2009 2010 2010
Utility Consumption Cost/Year Consumption Cost/Year
Electricity$kWh 304,459 $166,653 287,513 $133,177
No. 2 Fuel Oil $
Gallons
28,098 $104,785 27,243 $ 84,597
Ttl Energy Costs $271,438 $217,774
A benchmark measure of energy use relative to other similar function
buildings in the area is the Energy Use Index (EUI), which takes the
total annual energy used by the facility divided by the square footage
area of the building, for a value expressed in terms of kBTU/SF.
This number can then be compared to other buildings to see if it is
about average, higher or lower than similar buildings in the area.
Likewise, the Energy Cost Index (ECI) is the cost of all energy used
by the building expressed in $/SF of building area. The comparative
values for the subject building are listed in Table 2 below:
Table 2
Stebbins
Tukurngailnguq
K$12 School
Saint Michael
Andrews K$12
School (neigh$
boring village)
Average for
All BSSD
Schools
Energy Use Index (EUI)
kBTU/SF Avg 2009, 2010
133.0 153.1 125.3
Energy Cost Index (ECI)
Average 2009, 2010
$6.98 $7.04 $6.73
Various Energy Efficiency Measures (EEMs) have been analyzed for
this building to determine if they would be applicable for energy
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
5
savings with reasonably good payback periods. Those EEMs that
have a payback period or those that are recommended for code
compliance, life cycle replacement, or other reasons are also
included.
Specific EEMs recommended for this facility are detailed in the
attached AkWarm Energy Audit Report along with specific payback
times, as well as estimated installation costs and estimated energy
savings. The higher priority items are summarized below:
a. Building HVAC Controls
i. The building heating, ventilation and air conditioning
(HVAC) system is currently operated by an electric
control system that runs equipment using time clocks,
thermostats and some manual over rides. It is
recommended that the existing control system be
replaced with an electronic control system. This will
allow greater control of the HVAC systems, providing
more communication between devices/spaces and
easier programming. It will also keep the controls
relatively simple for maintenance personnel to work
with.
ii. Upgrading controls would overlap with other
recommended work described below so it is difficult to
identify the savings and payback of this upgrade
alone. An estimate of $60,000 would be reasonable,
with a savings of about 10% and a pay back of
approximately 2.5 years.
b. Building Ventilation
i. The main ventilation system for the building consists
of a supply fan and an exhaust fan. The outside air
and exhaust air pass through an energy recovery coil
to help capture some of the heat in the exhaust air
stream. This is a very inefficient way to provide
ventilation for the school. The energy recover coil
only captures a small amount of the heat in the
exhaust air (roughly 35%) while the rest is blown out
of the building. It is recommended that the system be
reconfigured to provide a bypass damper between the
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
6
exhaust and outside air ducts in order to reuse the
heated air in the exhaust stream. There are code
related issues that need to be addressed for this to be
done, which are described in more detail further down
in this report. The cost estimate for this work is about
$40,000, with a savings around 10$15% and a
payback of approximately 1.2 years.
c. Carbon Dioxide (CO2) Monitoring
i. CO2 sensors can be utilized to help reduce the amount
of outside air drawn into the building. Rather than
supply a set minimum amount of outside air during
ventilation fan operation (15% of the total fan air
volume, for example) the outside air can be varied to
maintain the CO2 levels below a determined setpoint,
typically 750 parts per million for schools. This often
results in less outside air being drawn into the
building, which reduces the amount of energy needed
to heat the air.
ii. The above changes to ventilation fan control would be
integral to a controls upgrade, but if this was the only
work performed, and only for the gymnasium air
handler, it would provide an estimated 1% annual
energy savings at a cost of approximately $20,000,
with an expected payback of about 6.2 years. This
appears to be a small gain but along with other
upgrades it will have an added impact on energy
savings.
d. Pumps
i. The main constant volume heating circulations pumps
for the school can be changed out for variable speed
(VFD) pumps. VFD pumps can run at lower speeds
when the school has a low heating demand, which will
save power and reduce cost. The main circulation
pump can also be controlled to only run when there is
a heating demand, rather than run on a time clock as
it currently does.
ii. The constant duty domestic hot water recirculation
pump can be replaced with a pump that runs on an
electric timer and only operates during school hours.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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iii. The utilidor heat trace pump and the domestic water
service recirculation pump can both be operated
based on the outside air temperature rather than run
constantly as they currently are.
iv. The pump changes will cost approximately $30,000,
provide roughly 5% energy savings for the building
with a payback of about 2.4 years.
e. Thermostat Afterhours Setback: The school heat is
currently controlled such that the building operates with Day
and Night temperature settings, with hours set using a time
clock and temperatures adjusted using one of five Night
setback thermostats. This system has inherent flaws that
make it undesirable. It is recommended that each space be
provided with a programmable thermostat with schedules
set to match the occupancy of the space. In addition it is
recommended that all spaces have their temperatures
reduced to 60 degrees F when unoccupied. Again this work
is linked to an overall building controls upgrade, but the
approximate cost would be $6,400, with an energy savings
of about 5% and payback of less than 1$year.
f. Add Occupancy Sensors for Lighting: Occupancy sensors
are recommended for most spaces in the building. The cost
is about $12,000, with a savings near 4% and payback
around 1$year.
g. Upgrade Exterior Lighting: There are 15 exterior wall
mounted light fixtures that use high pressure sodium (HPS)
lamps and only operate during dark times of the year. It is
recommended that the fixtures be replaced with light
emitting diode (LED) fixtures. If the fixtures are replaced
the energy savings will be approximately 1% at a cost of
about $22,500 and a payback of about 7.5 years.
In addition to EEMs, various Energy Conservation Measures (ECMs)
are recommended that were not part of the energy audit model.
Some involve a modest capital investment. Others are policies or
procedures that are followed by management and employees that
require no capital outlay. Examples of recommended ECMs for this
facility include:
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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1. Consider replacing Use infrared automatic lavatory faucets
and water closet flush valves in all restrooms.
2. If automatic flushing is not desired then install water closet
flushometer valves for dual level flushing.
3. Turn off computers, monitors, printers, faxes, coffee
makers, etc when leaving the office for the day. Turn off
computers, monitors, printers, faxes, coffee makers, etc.,
when leaving for the day. These devices can also be
plugged into power strips equipped with occupancy sensors
so they will automatically turn off when the building is not in
use.
4. Provide occupancy sensors for unoccupied spaces such as
bathrooms, storage spaces and utility rooms. The payback
for this change may never be realized but the retrofit serves
to ensure that unseen lighting is not accidentally left on for
long periods of time such as summer break.
5. Install an illuminated indicator to show if attic lighting is on.
It is not practical to install occupancy sensors in the attic
due to the large area. However small light bulbs or
illuminated switches could be installed on the walls just
outside the attic access doors to indicate if the lighting is on.
This will help to reduce the likelihood of attic lights
accidentally being left on.
6. Disconnect refrigeration equipment over the summer,
including walk$in units and residential style refrigerators
throughout the building. This will save approximately
$2,000/year.
The priority recommendations in the detailed report are estimated to
save $82,603/year, with an installed cost of $169,805, for a 2.1 year
payback. This does not include design or CA services, but overall it
does indicate a cost effective energy savings program.
3. Audit and Analysis Background:
a. Program Description: This audit included services to identify,
develop, and evaluate energy efficiency measures at the
subject building. The scope of this project included evaluating
the building shell, lighting, other electrical systems, and
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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heating, ventilating, and air conditioning (HVAC) equipment.
Measures were selected such that an overall simple payback
period of 8 years or less could be achieved.
b. Audit Description and Methodology: Preliminary audit
information was gathered in preparation for the site survey,
including benchmark utility consumption data, floor and lighting
plans, and equipment schedules where available. A site visit
was performed to inventory and evaluate the actual building
condition, including:
i. Building envelope (roof, windows, etc)
ii. Heating, ventilating, and air conditioning
iii. Lighting systems and controls
iv. Building specific equipment
v. Plumbing systems
c. Method of Analysis: The information gathered prior to the site
visit and at the site visit is entered into AkWarm$C, an energy
modeling developed for Alaska Housing Finance Corporation
(AHFC) specifically to identify forecasted energy consumption
which can be compared to actual energy consumption.
AkWarm$C also has some pre$programmed EEM retrofit
options that can be analyzed with energy savings forecasted
based on occupancy schedules, utility rates, building
construction type, building function, existing conditions, and
climatic data that is already uploaded to the program based on
the zip code of the building. When new equipment is
proposed, energy consumption is calculated based on
manufacturer’s cataloged information.
Cost savings are calculated based on the historical energy
costs for the building. Installation costs include labor and
equipment to estimate the full up$front investment required to
implement a change, but design and construction management
costs are excluded. Costs are derived from Means Cost Data,
industry publications, experience of the auditor, local
contractors and equipment suppliers. Maintenance savings
are calculated were applicable and are added to the energy
savings for each EEM.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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The cost and savings are applied and a simple payback and
simple return on investment (ROI) is calculated. The simple
payback is based on the number of years that it takes for the
savings to pay back the net installation cost (Net Installation
divided by Net Savings.)
A simple life$time calculation is shown for each EEM. The life$
time for each EEM is estimated based on the typical life of the
equipment being replaced or altered. The energy savings is
extrapolated throughout the life$time of the EEM. The total
energy savings is calculated as the total life$time multiplied by
the yearly savings.
d. Limitations of the Study: All results are dependent on the
quality of input data provided, and can only act as an
approximation. In some instances, several methods may
achieve the identified savings. This report is not intended as a
final design document. A design professional, licensed to
practice in Alaska and in the appropriate discipline, who is
following the recommendations, shall accept full responsibility
and liability for the results. Budgetary estimates for
engineering and design of these projects in not included in the
cost estimate for each measure, but these costs generally run
around 15% of the cost of the work.
4. Acknowledgements: We wish to acknowledge the help of numerous
individuals who have contributed information that was used to prepare
this report, including:
a. Alaska Housing Finance Corporation (Grantor): AHFC
provided the grant funds, contracting agreements, guidelines,
and technical direction for providing the audits. AHFC
reviewed and approved the final short list of buildings to be
audited based on the recommendation of the Technical
Service Provider (TSP).
b. Bering Strait School District (Owner): The BSSD provided
building access, original construction plans, two years energy
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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billing data, building schedules and functions, as well as other
resources needed to perform the audit.
c. Central Alaska Engineering Company (Benchmark TSP):
Central Alaska Engineering Company compiled the data
received from the BSSD and entered that data into the
statewide building database, called the Alaska Retrofit
Information System (ARIS).
d. Richard S. Armstrong, PE, LLC (Audit TSP): This is the
TSP who was awarded the projects in the Arctic Slope
Regional Corporation, Bering Straits area, and the Nana area.
The firm gathered all relevant benchmark information provided
to them, cataloged which buildings would have the greatest
potential payback, and prioritized buildings to be audited based
on numerous factors, including the Energy Use Index (EUI),
the Energy Cost Index (ECI), the age of the building, the size
of the building, the location of the building, the function of the
building, and the availability of plans for the building. They
also trained their selected sub$contracted auditors, assigned
auditors to the selected buildings, and performed quality
control reviews of the resulting audits. They prepared a listing
of potential EEMs that each auditor must consider, as well as
the potential EEMs that the individual auditor may notice in the
course of his audit. Richard S. Armstrong, PE, LLC also
performed some of the audits to assure current knowledge of
existing conditions.
5. Building Description and Function: The subject structure is called
the Stebbins Tukurngailnguq School, which was constructed in 1992.
The building serves as a kindergarten through twelfth grade (K$12)
educational facility, which includes classrooms, administrative offices,
a commercial kitchen, a multi$purpose room/cafeteria, a gymnasium,
locker rooms, vocational education room with shop, restrooms, and
multiple storage and utility spaces. The building is primarily a single
story structure with limited second story occupancy consisting of a
mezzanine around 3/4 of the gymnasium, one apartment, one multi$
person sleeping room and/or meeting room and storage. An enclosed
attic space in the center of the school serves as a mechanical room.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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The gymnasium fan room is connected to the gymnasium mezzanine.
The entire school is on raised piles with about 4$feet of space
between the bottom of the building and the surface of the ground.
The gymnasium, student shop, multi$purpose room, north and south
entries have high ceilings extending to the underside of the roof. This
is also true of three locations in the east corridor along the classrooms
where clerestorys are installed. Corridors and locker rooms have
ceilings just under 9 feet high. Classrooms have “peaked” ceilings
partly following the roof slope with an average height of about 10 feet.
The offices and kitchen and various storage and utility rooms have
ceilings heights around 9.5 feet high. The gymnasium has an average
ceiling height of 23.5 feet. The building roof is constructed of TJL/W
and other similar ‘TJ’ style trusses with plywood and metal roofing on
the exterior and 2$layers of gypsum wall board on the interior. The
interstitial space is filled with R$60 fiberglass batt. The bottom of the
building is constructed of TJL/W trusses with plywood on the interior,
gypsum wall board on the exterior and R$60 blown$in fiberglass. The
exterior walls are 2x10 wood studs with gypsum wall board on the
interior, plywood, gypsum wall board and cedar siding on the exterior,
and filled with R$30 batt insulation. The overall building design and
construction is similar to many schools that were built in Western
Alaska at that time. The building is in good condition overall and
appears to operate more or less as designed. The building is
occupied from the middle of August through the middle of May. The
school is unused during the summer months.
a. Heating System: The school heating plant is in the
northwest corner of the school building. The building heating
system consists of two Weil McLain cast iron sectional boilers
with Gordon$Piatt model R8.3$0$15 single$stage burners.
The boilers provide heat to the school buildings and one
teacher housing building. The boilers are original to the 1992
school construction. Hot glycol is circulated around the
building using a Grunfos model UMC 65$80 (labeled H$7), 3$
speed circulator, set at speed 2, with a 2 HP motor. The
pump is a duplex setup with primary and back up pumps
mounted on the same frame. The pump is operated on a
time clock so it runs constantly during the school day. The
pump is also connected to the Night set back thermostats in
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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the building to operate as needed outside of school hours.
Both ventilation fans (V$1 and V$12) are equipped with
heating coils and each is served by a dedicated duplex pump
arrangement. Pump H$9 serves V$1 and is a Grundfos UMC
65$80, 3$speed unit, set at speed 2, with a 1 HP motor.
Pump H$10 serves V$12 and is a Grundfos UMC 65$80, 3$
speed unit, set at speed 2, with a 3/4 HP motor. A heat trace
pump (H$8) provides heat for the utilidors under the building
and runs constantly. It is a Grundfos UMS 50$80, 3$speed
unit, set at speed 3, with a 1/3 HP motor. None of the pumps
are equipped with variable frequency drives (VFD), so they
run at full speed when they operate. Heat is distributed
throughout the building using fintube baseboard in most
perimeter and some interior spaces, cabinet unit heaters in
the gymnasium, vestibules, and corridors, unit heaters in
utility spaces, and some supplemental heat through tempered
ventilation air.
b. Ventilation System: There are two ventilation fans in the
building as well as multiple exhaust fans. V$1 is the fan that
serves all of the building except the gymnasium. It is also
designed to provide make$up air for the kitchen cooking line
exhaust fan, V$9. V$12 serves the gymnasium. V$3 is the
relief/exhaust fan for V$1 and is interlocked to operate with
that unit. V$1 is operated using a time clock and the flow rate
is adjusted using a VFD. It was designed to run from 3,000
cfm up to 10,700 cfm. The higher flow rate is designed to be
used for make$up air when V$9 operates. V$1 provides 100%
outside air. V$3 operates with V$1 and has a VFD to vary its
speed to track V$1 up to 9,100 cfm and provides 100%
relief/exhaust. An energy recovery device called a tilt coil (V$
2) is installed in the outside and relief/exhaust ducts. It is
intended to absorb heat from the relief/exhaust air stream
and transfer it to the outside air stream before it enters V$1.
The device appears to be operational and provides heat
transfer with about 35% efficiency. Heating of ventilation
(outside) air is a significant source of energy consumption for
commercial buildings. State of Alaska design codes mandate
that certain quantities of ventilation air must be provided.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
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However, there are devices and strategies that can be
employed to regulate the introduction of ventilation air so
energy is not wasted, such as demand control ventilation
based on CO2 concentration.
c. Plumbing System: Water is provided from the village utility
and there is not any on$site storage. Fixtures include water
closets, lavatories, showers, classroom sinks, mop sinks,
and large sinks for cooking. Most fixtures are located in
bathrooms, locker rooms, custodial closets and the
commercial kitchen. Classrooms for the younger elementary
school children have adjoining water closets and lavatories
as well as sinks in the classroom.
d. Domestic Hot Water: How water for most of the building is
generated using a shell in tube heat exchanger (H$26) and
stored in a 300$gallon insulated tank (H$11) at about 130
degrees F. Hot water is supplied to the kitchen using a 70$
gallon oil fired water heater (P16) that draws water from H$
11. The kitchen water is supplied over 140 degrees F. No
additional hot water storage is provided. There is a hot water
recirculation pump that runs constantly to provide instant hot
water to remote fixtures.
e. Lighting: Typical lighting used throughout occupied spaces
in the building is provided with T$8 fluorescent fixtures using
electronic ballasts and controlled manually with a single
toggle switch. The gymnasium has high bay lighting fixtures
with (5) 2$tube, plug$in, compact fluorescent bulbs at 55 watts
each. Gymnasium lights are switched on manually. The
multi$purpose room has two high pressure sodium (HPS)
fixtures that are operated manually. Exterior lights are 150
watts HPS wall packs. Exterior lights operate using daylight
sensors.
f. Fire Sprinkler: The building is equipped with a fire sprinkler
protection system throughout. Water is stored in bulk tanks
across the road from the school and piped underground to
the sprinkler riser in the mechanical room. Water is
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
15
circulated in the water line between the school and water
treatment building across the road to keep the line from
freezing.
g. Additional Buildings: The fuel oil use benchmarked for this
building included fuel used in teacher housing. Some of the
teacher housing buildings have their own boilers and some
use heating water from the school boilers. The commercial
energy audit only takes the school building into consideration
so the additional floor area and construction types for the
additional buildings are not taken into account. However, in
order to make the model fuel oil consumption match the
benchmark data the school inputs were "padded" to make up
the difference. Specifically the infiltration rate was set very
high. The additional fuel used by "infiltration" will not be
affected since no recommendations are made to improve the
building envelope. The overall energy saved by the
recommended upgrades and/or operational adjustments
would be the same whether the teacher housing fuel use was
taken into consideration or not. All that being stated, it is
highly recommended that energy upgrades be made to
teacher housing as the building envelopes and heating
equipment are very inefficient.
6. Historic Energy Consumption: Energy consumption is modeled
within the AkWarm$C program. The program only analyzes 12
months of data, so where 24 months of data are available, the data is
averaged and input to AkWarm$C to provide more accuracy. The
energy consumption data is presented and graphed in the attached
AkWarm$C program results.
Based on the benchmark energy data for 2009 and 2010, the average
electric consumption for the building was 295,986 kWh/year at an
average cost of $149,915/year. The average fuel oil consumption was
27,672 gallons/year, at an average annual cost of $94,692/year.
7. Energy Efficiency Measures Considered or Recommended: The
building was examined for application of a multitude of potential EEMs
that are discussed below. Those EEMs that appear to have an
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
16
application for the subject building are further analyzed for estimated
payback periods, either within the AkWarm$C program or separately
within this report. The accuracy of the cost estimates and paybacks
varies significantly due to a multitude of conditions, but is estimated to
be approximately +/$ 25%. Assumptions made regarding energy costs
and the life of the EEM, noting that post$construction measurement
and verification are based on energy savings, not energy cost
savings. Many of the selected EEMs are analyzed within the
AkWarm$C program using the schedules and estimated costs input
into the model.
a. Occupancy Sensors for Lighting: The occupied spaces in
the building can be retrofitted with occupancy sensors so the
lights are only on when rooms are in use. This applies to
hallways, classrooms, offices, storage rooms, assembly rooms,
and restrooms. Though most rooms will be occupied during
the majority of the school day, certain times of the day, such as
lunchtime, will cause most rooms to be empty. Occupancy
sensors have improved over the years, increasing their
reliability and reducing false starts and stops. Dual technology
occupancy sensors combine passive infrared (PIR) and
ultrasonic technologies into one unit to achieve precise
coverage and to eliminate false triggers. The sensors can be
mounted on the wall in place of the existing light switch, or on
the ceiling where more uniform coverage and detection is
desired in a larger room. Wall switch type automatic
occupancy sensors are appropriate for small rooms, such as
utility rooms, one person toilet rooms, small open offices, and
places where the wall switch is located such that occupants
can be detected with line$of$sight from anywhere in the room.
They can turn lights on and off based on both occupancy and
ambient light levels. Many also offer the option of manual
override switches, allowing the occupant to adjust lighting
levels or turn off the lights all together. Devices in break
rooms, utility rooms, storage rooms, small offices, and small
open (non$partitioned) bathrooms can save up to 60% of the
cost of the lighting where rooms are infrequently used, but the
lights are typically left on. Occupancy sensors are not
recommended for basements and crawlspaces since the
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
17
spaces are typically broken up with shelving, boxes and
partition walls, requiring too many sensors to be installed. It is
recommended that light or illuminated switches be installed
above the floor near crawlspace accesses so it is possible to
see whether crawlspace lights have been turned off without
entering the crawlspace.
b. Exterior Lighting Upgrade: High$intensity discharge (HID)
fixtures, such as high pressure sodium (HPS), are commonly
used for building exterior lighting in Alaska because they
perform well in cold weather and are more efficient than many
other types of lighting. However, light emitting diode (LED)
fixtures are proving to be a viable alternative to HPS. LED
fixtures use nano reflector technology with drivers offering
50,000 hours life, about 6 years, as compared to only 20,000
hours with high$intensity discharge (HID) fixtures. LED fixtures
offer the instant$on feature of fluorescent fixtures but use
significantly less energy than the HID fixtures. LEDs have an
added benefit of operating more efficiently (using less power)
as the ambient temperature gets colder, and some have been
factory tested to operate down to $40 deg F (actual installations
in Antarctica and Fairbanks indicate they operate at lower
temperatures as well) depending on manufacturer. The
proposed LED fixtures are dark sky compliant, using 100%
cutoff optics to reduce light pollution. LEDs provide a different
type of light than HPS, both in color and lumen output, that has
the effect of providing a clearer, brighter light while using less
power than a HPS bulb. The following chart indicates energy
savings for various exterior building mounted light fixtures (MH
Metal Halide; HSP High Pressure Sodium) using Scotopic
lighting measurements:
HID Lamp
HID
System
Wattage
LED
System
Wattage
Energy
Savings
(%)
150W HPS 188W 54W 71
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
18
c. HVAC Control: The building HVAC systems are operated
using basic electric controls. They provide effective control
when looking at the building as a whole but they are not able to
address the unique requirements of each space, specifically
with regard to temperature. It is recommended that the
existing HVAC controls be upgraded to an electronic system
that will provide tighter control of temperature and ventilation
throughout the building. Programmable thermostats will allow
the heat demand for each space to be specifically programmed
to match the occupancy of the space. Pressure and/or
temperature sensors throughout the building will enable the
ventilation fans to adjust speed and amount of outside air to
meet occupancy demands. This will require the installation of
new thermostats and sensors, actuators, valve motors, control
dampers, control panel(s) and low (24) voltage wiring
throughout the building. Most of the wiring can be installed in
the attics and above suspended ceilings, making for a simpler
installation and cleaner appearance.
d. Ventilation: The main ventilation fan for the building, V$1,
supplies 100% outside air and the relief/exhaust fan, V$3,
sends 100% of its airflow out of the building. An energy
recovery device known as a tilt coil is installed between the
outside and relief/exhaust duct to reclaim some of the heat
from the outgoing air stream and dump it into the incoming
airstream. The device operates at roughly 35% efficiency,
meaning 65% of the heat in the outgoing airstream is thrown
away. A better, more efficient design for air handling is to
recirculate some of the relief air back into the incoming air
stream and use it to temper the outside air. If the outside air
stream was set at 15% then 85% of the return air is being
reused by ventilation system. This allows 85% of the heat to
be reclaimed rather than just 65%. This will require installing a
bypass duct and damper between the outside and
relief/exhaust ducts, and another damper to regulate the
amount of outside air drawn into the fan. Ideally the bypass
duct would be installed on the side of the tilt coil that is closest
to the fan equipment in order to continue using the tilt coil to
extract heat from the relief air before it exits the building. The
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
19
plans indicate that V$3 serves as the return, exhaust and relief
fan, including exhausting air from the locker rooms. Since
code does not permit the recirculation of exhaust air into the
building a dedicated exhaust fan will have to be provided for
the locker rooms, and any other such spaces, and the
ductwork will need to be modified. Given the potential for cost
savings with these changes they would be very worthwhile.
e. Ventilation Control: The ventilation fans serving the school
were designed to function using time clocks and electrical
connections with other fans. It appears that the units are
working as designed however control upgrades can be made
that will make it simpler to program the fan schedules and
allow the fans to vary their performance based on space
conditions. The following items would improve the
performance of the fan units and reduce the amount of energy
they consume:
i. Operation Schedules: Time clocks are analog devices
that function using markers fastened to a dial. They
perform well and are very reliable. However setting them
up is time consuming so once a schedule is set it is not
likely to change. This appears to be the case with main
ventilation fan, which is running 7:00 A.M. to 11:00 P.M.
every day including the weekends. This does not fit the
school usage and is wasting energy. There also appears
to be concern about VFD operation because the VFD
was locked in at 30 hertz (1/2 speed). The following
programming changes are recommended:
1. V1, Main School Building (Suggested
Operation) – Operate the unit only during school
hours. Set the outside air and bypass dampers to
maintain 15% outside airflow and set the VFD
speed such that 15% outside air meets the
ventilation requirement of the school (to be
determined). When the kitchen exhaust fan is
operating the outside air damper can open as
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
20
needed to maintain a positive building pressure. If
the building requires cooling the outside air damper
can open and the fan speed can increase to meet
the demand. Replace the front office fan override
switch with an electronic timer.
2. V12, Gymnasium – Operate the unit during
known periods of occupancy such as lunch hours
and scheduled “open gym” hours. Provide with
VFD to vary airflow based on ventilation and
cooling requirements. Replace the front office fan
override switch with an electronic timer.
ii. Carbon Dioxide (CO2) Monitoring: The amount of CO2
in a building has been shown to have a direct effect on
the performance of the occupants in the building. High
levels of CO2 cause occupants to feel sleepy and lose
concentration. It is also an indication that other indoor
contaminants, such as volatile organic compounds
(VOCs), odors and excessive humidity are likely
increasing in concentration. For these reasons
ventilation air is required by code to refresh indoor
building air. Typically the ventilation rate is determined
based on the number of occupants and space sizes. In
many cases this over$ventilates the space. Another
method of ventilating spaces is called demand control
ventilation, which entails varying the amount of outside
air supplied based on CO2 levels in the building.
Sensors can be placed in spaces throughout the building
(preferred) or in the return air duct at the ventilation fans,
and the fan outside air dampers can be modulated to
increase or decrease the outside air delivered to the
building. This modification applies specifically to V$12
and may also be appropriate for V$1.
f. VFD Heating Pumps: In most cases heating circulators are
designed for greater flow rates than is needed during normal
operation. Bypass valves are installed to allow the constant
volume of flow to continue even when a small amount of that
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
21
flow is providing heat. Energy is wasted circulating heated
glycol that is not needed. There are a number of pumps on
the market that have variable frequency drives (VFD), which
allow the speed of the motor to be adjusted to match the flow
rate demand. Pump affinity laws show that motor speed and
power have a cubic mathematical relationship to each other.
As the pump speed is reduced “X” RPM the power
consumption is reduced by X1/3 watts (or horsepower), showing
that a small change in pump speed has an amplified affect on
power input. Operating pumps at lower speeds when there is
lower flow demand significantly reduces power consumption. It
is recommended that the heating circulators be replaced with
VFD pumps so power savings can be realized.
g. Boiler Temperature Outdoor Air Reset: As the outside air
temperature varies building heat loss varies as well, losing
heat at a faster rate as the ambient temperature drops. Boiler
systems are typically sized to meet the heating demands of the
coldest expected temperatures. These extreme temperatures
may only occur for short durations in a given winter and will
vary in frequency and length year to year. Most cast iron
sectional boilers supply heating water at the same temperature
year$round. During periods of warmer weather in the heating
season high heating water supply temperatures may cause
space temperatures to overshoot setpoints because the hot
boiler water dumps heat into the building at a faster rate than
the building is losing it, leading to occupant discomfort. This
will also cause the boilers to cycle more often since it takes
less time to heat the returning water, putting unnecessary wear
on the boilers. A common way of handling this issue is to use
an outdoor reset controller to reduce the heating loop
temperature so that heat is transferred into the building closer
to the rate at which the building is losing heat. Outdoor reset
varies the boiler or heating loop water temperature based on
the ambient temperature – increasing the water temperature
when outdoor conditions are cold and decreasing water
temperature for warmer outdoor conditions. It was observed
on site that maintenance personnel were manually adjusting
the boiler temperature to give the same effect. In order to
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
22
maintain tighter control and prevent issues such as setting the
boiler temperature too low (causing the boiler to condense or
providing inadequate heating water temperatures for the hot
water generators), or forgetting to reset the boiler temperature,
it is recommended that a controller be installed that will
perform the outdoor reset automatically. There is not a
provision for simulating this in the AkWarm$C program so no
energy savings are considered here. However it is
recommended that a licensed professional engineer perform
the design for installation of this controller at which time an
energy savings analysis could be performed.
h. Domestic Hot Water Recirculation: The domestic hot water
system is provided with a small pump that circulates the hot
water loop back to the water heater so there is always hot
water available at the furthest fixtures in the building. This
pump operates constantly, which is unnecessary since hot
water is only needed during building occupancy. It is
recommended that controls be provide for the hot water
recirculation pump so it will only run during school hours, which
will reduce the energy consumed by the pump.
i. Waste Heat: The school building is not currently supplied with
waste heat. However the school is less than 0.5 miles from the
village power utility. If the school was supplied with waste heat
from the village power plant it would have a tremendous impact
on energy savings for the school, likely surpassing fuel oil as
the primary heating source. Connecting the school heating
plant to the village power plant would require a large capital
investment but could have a payback of 10$15 years. No
investigation has been performed on the amount of heat that
would be available from the power plant, which would require a
thorough engineering analysis. It is recommended that a
preliminary investigation be performed to determine the
viability of this option.
j. Fuel Oil Metering: It is recommended that fuel oil meters be
installed to track the amount of fuel used by the boilers and
electric generator. The only methods currently used on site for
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
23
tracking fuel usage are recording the amount of fuel put into
bulk fuel storage tanks when they are refilled and maintenance
personnel manually recording the fuel levels in the tanks.
Neither method is able to provide precise information nor does
it give a detailed picture of the rate at which fuel is used. In
order to understand current and future fuel consumption, a fuel
meter should be installed on the boiler fuel line and another on
the generator fuel line. The Pathfinder Instruments FM$200
meter is for fuel pipes sized ¾” to 1” (different meters, must
specify pipe size), and they cost around $225 each. They
operate at a flow range of 4$20 GPM. These are mechanical
meters with strainers and 3$digid display that shows both
present fuel use, and cumulative fuel use. This information
can be tied into the building DDC system and saved as trend
log data and/or the meter can have an analog dial for visual
inspection. Any ESCO contract, or AHFC financed contract
will require fuel metering to verify paybacks of energy
conservation measures. Electronic turbine meters are also
available. See pathfinderinstruments.com for product
information.
8. Interactive Effects of Projects: The AkWarm$C program calculates
savings assuming that all recommended EEM are implemented. If
some EEMs are not implemented, savings for the remaining EEMs will
be affected, in some cases positively, and in others, negatively. For
example, if the fan motors are not replaced with premium efficiency
motors, then the savings for the project to install variable speed drives
(VFDs) on the fans will be increased.
In general, all projects were evaluated sequentially so that energy
savings associated with one EEM would not be attributed to another
EEM as well. For example, the night setback EEM was analyzed
using the fan and heating load profile that will be achieved after
installation of the VFD project is completed. By modeling the
recommended projects sequentially, the analysis accounts for
interactive effects between the EEMs and does not “double count”
savings.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
24
Interior lighting, plug loads, facility equipment, and occupants
generate heat within the building. When the building is in cooling
mode, these contribute to the overall cooling demands of the
building; therefore lighting efficiency improvements will reduce
cooling requirements on air conditioned buildings. Conversely,
lighting efficiency improvements are anticipated to increase heating
requirements slightly. Heating penalties are included in the lighting
project analysis that is performed by AkWarm$C.
9. Loan Program: The Alaska Housing Finance Corporation (AHFC)
Alaska Energy Efficiency Revolving Loan Fund (AEERLF) is a State of
Alaska program enacted by the Alaska Sustainable Energy Act
(senate Bill 220, A.S. 18.56.855, “Energy Efficiency Revolving Loan
Fund). The AEERLF will provide loans for energy efficiency retrofits
to public facilities via the Retrofit Energy Assessment for Loan System
(REAL). As defined in 15 AAC 155.605, the program may finance
energy efficiency improvements to buildings owned by:
a. Regional educational attendance areas;
b. Municipal governments, including political subdivisions of
municipal governments;
c. The University of Alaska;
d. Political subdivisions of the State of Alaska, or
e. The State of Alaska
Native corporations, tribal entities, and subsidiaries of the federal
government are not eligible for loans under this program.
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
25
Appendix A: Photos
North Elevation North Entrance, Classrooms on left, Administration
and Mechanical Room on right, Gymnasium roof visible on right
School pile foundation
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
26
West Elevation – Gymnasium wall, Student Shop entrance
Southwest Corner Elevation – Classrooms and South Entrance
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
27
Southeast Corner – Classrooms and South Entrance ramp
West Elevation – Classrooms, Clerestorys on roof
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
28
Typical Hallway, low ceiling
Typical Hallway, high ceiling with Clerestory
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
29
Typical Classroom
MultiPurpose Room/Caffeteria
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
30
Gymnasium, North wall and Mezzanine
Gymnasium, Southeast corner and Mezzanine
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
31
Kitchen cooking equipment under exhaust hood
Kitchen dish washing equipment
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
32
Kitchen walk in refrigerator/freezer and rolling refrigerator
Walk in refrigerator/freezer condensing units in attic Fan Room
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
33
Main building air handler (VF1)
VF1 variable frequency drive (VFD)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
34
VF1 Time Clock
Main building relief air fan (V3)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
35
Gymnasium air handler (VF12)
Oil fired boiler (typical of 2)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
36
Heating circulation pumps
School domestic hot water storage tank (H11)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
37
Domestic hot water heat exchanger serving H11 (H26)
Kitchen domestic water heater (P16)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
38
Typical outside air damper in Mechanical Room
Night and Day thermostats (typical of 5 in building)
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
39
Stebbins Village, Ariel View Village Power Utility School
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
40
Appendix B: AK Warm Energy Model
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 1
ENERGY AUDIT REPORT – PROJECT SUMMARY – Created 3/2/2012 9:31 AM
General Project Information
PROJECT INFORMATION AUDITOR INFORMATION
Building: Stebbins K-12 School (Tukurngailnguq School) Auditor Company: RSA Engineering, Inc.
Address: Stebbins Alaska 99671 Auditor Name: Adam Wilson
City: Stebbins Auditor Address: 2522 Arctic Blvd
Suite 200
Anchorage, AK 99503
Client Name: Richard Ried
Client Address: PO Box 225
Unalakleet AK 99684
Auditor Phone: (907) 276-0521
Auditor FAX:
Client Phone: (907) 624-3611 Auditor Comment:
Client FAX:
Design Data
Building Area: 36,935 square feet Design Heating Load: Design Loss at Space: 1,087,664
Btu/hour
with Distribution Losses: 1,087,664 Btu/hour
Plant Input Rating assuming 82.0% Plant Efficiency and
25% Safety Margin: 1,658,024 Btu/hour
Note: Additional Capacity should be added for DHW load,
if served.
Typical Occupancy: 218 people Design Indoor Temperature: 71.7 deg F (building average)
Actual City: Stebbins Design Outdoor Temperature: -34 deg F
Weather/Fuel City: Stebbins Heating Degree Days: 14,272 deg F-days
Utility Information
Electric Utility: AVEC-Stebbins - Commercial - Lg Natural Gas Provider: None
Average Annual Cost/kWh: $0.527/kWh Average Annual Cost/ccf: $0.000/ccf
Annual Energy Cost Estimate
Description Space
Heating
Space
Cooling
Water
Heating Lighting Refrige
ration
Other
Electric
al
Cooking Clothes
Drying
Ventilatio
n Fans
Service
Fees Total Cost
Existing
Building
$89,724 $0 $30,392 $75,838 $10,24
3
$30,65
7
$10,123 $0 $6,672 $60 $253,710
With
Proposed
Retrofits
$35,335 $0 $21,851 $60,793 $7,786 $30,70
3
$10,138 $0 $4,442 $60 $171,108
SAVINGS $54,390 $0 $8,542 $15,046 $2,456 -$47 -$14 $0 $2,230 $0 $82,603
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 2
$0
$50,000
$100,000
$150,000
$200,000
$250,000
$300,000
Existing Retrofit
Service Fees
Ventilation and Fans
Space Heating
Refrigeration
Other Electrical
Lighting
Domestic Hot Water
Cooking
Annual Energy Costs by End Use
$0
$50,000
$100,000
$150,000
$200,000
$250,000
$300,000
Existing Retrofit
#2 Oil Electricity
Annual Energy Costs by Fuel
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 3
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
1 Refrigeration: Walk-
in Freezer
Add new Seasonal
Shutdown
$1,108 $1 6775.00 0
2 Refrigeration: Walk
in Refrigerator
Add new Seasonal
Shutdown
$443 $1 2709.63 0
3 Refrigeration:
Moblie Refrigerator
in Kitchen
Add new Seasonal
Shutdown
$222 $1 1354.75 0
4 Refrigeration: Chest
Freezer
Add new Seasonal
Shutdown
$202 $1 1236.13 0
5 Refrigeration:
Refrigerators
Add new Seasonal
Shutdown
$100 $1 609.75 0
6 Setback Thermostat:
Gymnasium - 137
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Gymnasium - 137
space.
$1,414 $200 95.99 0.1
7 Setback Thermostat:
Voc. Ed. - 148
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Voc. Ed. - 148 space.
$1,042 $200 70.74 0.2
8 Setback Thermostat:
First/Second Grade -
104
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the First/Second Grade -
104 space.
$843 $200 57.22 0.2
9 Setback Thermostat:
History - 161
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the History - 161 space.
$733 $200 49.75 0.3
10 Setback Thermostat:
Home Economics -
159
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Home Economics - 159
space.
$730 $200 49.53 0.3
11 Setback Thermostat:
Itenerant Suite - 204
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Itenerant Suite - 204
space.
$718 $200 48.73 0.3
12 Lighting: Classroom,
Hallways - Type A3 -
Metalux
2P3MX340S36HLCW
M/ES2
Replace with 166 FLUOR
(3) T8 4' F32T8 32W
Standard Instant
StdElectronic and Remove
Manual Switching and Add
new Occupancy Sensor
$4,832 $700 42.73 0.1
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 4
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
13 Setback Thermostat:
Kindergarten - 103
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Kindergarten - 103
space.
$583 $200 39.56 0.3
14 Setback Thermostat:
Third/Fourth Grade -
106
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Third/Fourth Grade -
106 space.
$576 $200 39.10 0.3
15 Setback Thermostat:
Itenerant Suite - 203
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Itenerant Suite - 203
space.
$482 $200 32.72 0.4
16 Setback Thermostat:
Fifth/Sixth Grade -
127
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Fifth/Sixth Grade - 127
space.
$455 $200 30.89 0.4
17 Setback Thermostat:
Seventh/Eiighth
Grade - 133
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Seventh/Eiighth Grade
- 133 space.
$448 $200 30.40 0.4
18 Setback Thermostat:
Bilingual/Bicultural -
151
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Bilingual/Bicultural -
151 space.
$428 $200 29.06 0.5
19 Setback Thermostat:
Language - 160
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Language - 160 space.
$415 $200 28.20 0.5
20 Setback Thermostat:
Business - 155
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Business - 155 space.
$412 $200 27.99 0.5
21 Lighting: Classroom,
Hallways - Type A3 -
Metalux
2P3MX340S36HLCW
M/ES2 Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$3,163 $700 27.66 0.2
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 5
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
22 Setback Thermostat:
Math/Science - 154
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Math/Science - 154
space.
$366 $200 24.87 0.5
23 Setback Thermostat:
Weight Room- 147
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Weight Room- 147
space.
$340 $200 23.10 0.6
24 Setback Thermostat:
Elementary Resource
- 138
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Elementary Resource -
138 space.
$303 $200 20.59 0.7
25 Setback Thermostat:
High School
Resource - 139
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the High School Resource -
139 space.
$297 $200 20.14 0.7
26 Lighting: Classrooms,
Restrooms - Type B3
- Metalux
2MC340A125LCWM/
ES2
Remove Manual Switching
and Add new Occupancy
Sensor
$844 $300 17.42 0.4
27 Setback Thermostat:
Lab - 140
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Lab - 140 space.
$231 $200 15.71 0.9
28 Setback Thermostat:
Vestibule - 157
Implement a Heating
Temperature Unoccupied
Setback to 55.0 deg F for
the Vestibule - 157 space.
$191 $200 12.98 1
29 Lighting: Office -
Type A4 - Metalux
2P3MX440S48HLCW
M/ES2 Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$596 $300 12.17 0.5
30 Setback Thermostat:
Conference - 111
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Conference - 111
space.
$177 $200 12.02 1.1
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 6
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
31 Lighting: Office -
Type A4 - Metalux
2P3MX440S48HLCW
M/ES2
Replace with 10 FLUOR (4)
T8 4' F32T8 32W Standard
Instant StdElectronic and
Remove Manual Switching
and Add new Occupancy
Sensor
$385 $200 11.93 0.5
32 Setback Thermostat:
Staff - 113
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Staff - 113 space.
$163 $200 11.10 1.2
33 Setback Thermostat:
Couns/Sick - 110
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Couns/Sick - 110
space.
$161 $200 10.93 1.2
34 Setback Thermostat:
Principal - 112
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Principal - 112 space.
$142 $200 9.63 1.4
35 Setback Thermostat:
Corridor - 115
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 115 space.
$107 $200 7.30 1.9
36 Lighting: Classrooms,
Restrooms - Type B3
- Metalux
2MC340A125LCWM/
ES2 Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$398 $400 6.09 1
37 HVAC And DHW Change heat loop circ.
pumps to VFD, run
domestic hot water recirc.
pump on time clock or
temp. sensor, only operate
heat trace and domestic
water circ. pumps when
outside temperature is less
than 40 deg F
$12,641 $30,000 5.92 2.4
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 7
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
38 Ventilation Use CO2 sensors to
operate Gym AHU.
Provide exhaust fans for
the locker rooms to
disconnect them from V-1
return air. Install a bypass
damper between the
exhaust and outside air
ducts to allow tempering
of outside air intake.
Update all HVAC
equipment to DDC
controls.
$41,768 $100,000 5.62 2.4
39 Lighting: Corridor
Lighting - Type H -
Prudential
P1003M42-04SPL-SA
(1 lamp 4' fixture
according to site
visit)
Remove Manual Switching
and Add new Occupancy
Sensor
$341 $500 4.23 1.5
40 Lighting: Storage -
Type F - Metalux
SS240WG/SS-4FT
LCWM/ESE
Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$104 $200 3.18 1.9
41 Lighting: Kitchen
Storage - Type B2 -
Metalux
MCM240A125LCWM
/ES2 Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$104 $200 3.17 1.9
42 Lighting:
Multipurpose - Type
C - Holophane
BL2C40LHP27RX
Remove Manual Switching
and Add new Multi-Level
Switch
$374 $1,000 2.31 2.7
43 Setback Thermostat:
Vestibule - 100
Implement a Heating
Temperature Unoccupied
Setback to 55.0 deg F for
the Vestibule - 100 space.
$32 $200 2.17 6.2
44 Lighting: Corridor
Lighting - Type H -
Prudential
P1003M42-04SPL-SA
(1 lamp 4' fixture
according to site
visit) Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$99 $300 2.03 3
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 8
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
45 Setback Thermostat:
Corridor - 101
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 101 space.
$24 $200 1.65 8.2
46 Lighting: Similar to
Type H fixture with
T12 lights
Remove Manual Switching
and Add new Occupancy
Sensor
$33 $200 1.01 6.1
47 Lighting: Exterior
Lighting - Type L -
Holophane
PARK15AMP27CEBZ
AF1
Replace with 15 LED 80W
Module StdElectronic
$3,006 $22,500 0.83 7.5
48 Lighting: Locker
Room, Restrooms -
Type I - Holophane
7200-4-H1-WB-TB
Perimeter
Remove Manual Switching
and Add new Occupancy
Sensor
$25 $200 0.75 8.2
49 Lighting: Similar to
Type H fixture with
T12 lights
Replace with 3 FLUOR T8
4' F32T8 32W Standard
Instant StdElectronic
$17 $300 0.36 17.3
50 Lighting:
Multipurpose - Type
C - Holophane
BL2C40LHP27RX
Replace with 6 FLUOR (4)
T8 4' F32T8 32W Standard
(2) Instant StdElectronic
$210 $5,000 0.26 23.8
51 Setback Thermostat:
Corridor - 102
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 102 space.
$0 $200 0.00 Infinity
52 Setback Thermostat:
Reception - 108
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Reception - 108 space.
$0 $200 0.00 Infinity
53 Setback Thermostat:
Office - 123
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Office - 123 space.
$0 $200 0.00 Infinity
54 Setback Thermostat:
Commons - 130
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Commons - 130 space.
$0 $200 0.00 Infinity
55 Setback Thermostat:
Library/IMC - 141
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Library/IMC - 141
space.
$0 $200 0.00 Infinity
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 9
PRIORITY LIST – RECOMMENDED ENERGY EFFICIENCY MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
56 Lighting: Storage -
Type B2 - Metalux
MCM240A125LCWM
/ES2
Remove Manual Switching
and Add new Occupancy
Sensor
$0 $200 0.00 Infinity
57 Lighting: Mech/Elec,
Janitor, Storage -
Type F - Metalux
SS240WG/SS-4FT
LCWM/ESE
Remove Manual Switching
and Add new Occupancy
Sensor
-$225 $200 -6.96 -0.9
TOTAL $82,603 $169,805 5.89 2.1
ENERGY AUDIT REPORT – ENERGY EFFICIENT RECOMMENDATIONS
1. Building Envelope
Insulation
Rank Location Existing Type/R9Value Recommendation Type/R9
Value
Installed
Cost
Annual
Energy
Savings
Exterior Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
Windows and Glass Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
Air Leakage
Rank Location Estimated Air Leakage Recommended Air Leakage
Target
Installed
Cost
Annual
Energy
Savings
2. Mechanical Equipment
Mechanical
Rank Recommendation Installed
Cost
Annual
Energy
Savings
37 Change heat loop circ. pumps to VFD, run domestic hot water recirc. pump on time
clock or temp. sensor, only operate heat trace and domestic water circ. pumps
when outside temperature is less than 40 deg F
$30,000 $12,641
Setback Thermostat
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 10
6 Gymnasium - 137 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Gymnasium - 137
space.
$200 $1,414
7 Voc. Ed. - 148 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Voc. Ed. - 148 space.
$200 $1,042
8 First/Second Grade
- 104
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the First/Second Grade -
104 space.
$200 $843
9 History - 161 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the History - 161 space.
$200 $733
10 Home Economics -
159
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Home Economics - 159
space.
$200 $730
11 Itenerant Suite -
204
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Itenerant Suite - 204
space.
$200 $718
13 Kindergarten - 103 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Kindergarten - 103
space.
$200 $583
14 Third/Fourth Grade
- 106
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Third/Fourth Grade -
106 space.
$200 $576
15 Itenerant Suite -
203
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Itenerant Suite - 203
space.
$200 $482
16 Fifth/Sixth Grade -
127
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Fifth/Sixth Grade - 127
space.
$200 $455
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 11
17 Seventh/Eiighth
Grade - 133
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Seventh/Eiighth Grade
- 133 space.
$200 $448
18 Bilingual/Bicultural
- 151
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Bilingual/Bicultural -
151 space.
$200 $428
19 Language - 160 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Language - 160 space.
$200 $415
20 Business - 155 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Business - 155 space.
$200 $412
22 Math/Science - 154 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Math/Science - 154
space.
$200 $366
23 Weight Room- 147 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Weight Room- 147
space.
$200 $340
24 Elementary
Resource - 138
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Elementary Resource -
138 space.
$200 $303
25 High School
Resource - 139
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the High School Resource -
139 space.
$200 $297
27 Lab - 140 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Lab - 140 space.
$200 $231
28 Vestibule - 157 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 55.0 deg F for
the Vestibule - 157 space.
$200 $191
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 12
30 Conference - 111 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Conference - 111
space.
$200 $177
32 Staff - 113 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Staff - 113 space.
$200 $163
33 Couns/Sick - 110 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Couns/Sick - 110 space.
$200 $161
34 Principal - 112 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Principal - 112 space.
$200 $142
35 Corridor - 115 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 115 space.
$200 $107
43 Vestibule - 100 Existing Unoccupied Heating
Setpoint: 60.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 55.0 deg F for
the Vestibule - 100 space.
$200 $32
45 Corridor - 101 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 101 space.
$200 $24
51 Corridor - 102 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Corridor - 102 space.
$200 $0
52 Reception - 108 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Reception - 108 space.
$200 $0
53 Office - 123 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Office - 123 space.
$200 $0
54 Commons - 130 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Commons - 130 space.
$200 $0
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 13
55 Library/IMC - 141 Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Library/IMC - 141
space.
$200 $0
Ventilation
Rank Recommendation Cost Annual
Energy
Savings
38 Use CO2 sensors to operate Gym AHU. Provide exhaust fans for the locker rooms
to disconnect them from V-1 return air. Install a bypass damper between the
exhaust and outside air ducts to allow tempering of outside air intake. Update all
HVAC equipment to DDC controls.
$100,000 $41,768
3. Appliances and Lighting
Lighting Fixtures and Controls
Rank Location Existing Recommended Installed
Cost
Annual
Energy
Savings
12 Classroom,
Hallways - Type A3
- Metalux
2P3MX340S36HLC
WM/ES2
166 FLUOR (3) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Replace with 166 FLUOR (3)
T8 4' F32T8 32W Standard
Instant StdElectronic and
Remove Manual Switching
and Add new Occupancy
Sensor
$700 $4,832
21 Classroom,
Hallways - Type A3
- Metalux
2P3MX340S36HLC
WM/ES2 Perimeter
127 FLUOR (3) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$700 $3,163
26 Classrooms,
Restrooms - Type
B3 - Metalux
2MC340A125LCW
M/ES2
29 FLUOR (3) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$300 $844
29 Office - Type A4 -
Metalux
2P3MX440S48HLC
WM/ES2 Perimeter
18 FLUOR (4) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$300 $596
31 Office - Type A4 -
Metalux
2P3MX440S48HLC
WM/ES2
10 FLUOR (4) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Replace with 10 FLUOR (4)
T8 4' F32T8 32W Standard
Instant StdElectronic and
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $385
36 Classrooms,
Restrooms - Type
B3 - Metalux
2MC340A125LCW
M/ES2 Perimeter
30 FLUOR (3) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$400 $398
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 14
39 Corridor Lighting -
Type H - Prudential
P1003M42-04SPL-
SA (1 lamp 4'
fixture according to
site visit)
63 FLUOR T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$500 $341
40 Storage - Type F -
Metalux
SS240WG/SS-4FT
LCWM/ESE
Perimeter
6 FLUOR (2) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $104
41 Kitchen Storage -
Type B2 - Metalux
MCM240A125LCW
M/ES2 Perimeter
4 FLUOR (2) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $104
42 Multipurpose -
Type C - Holophane
BL2C40LHP27RX
6 HPS 400 Watt Magnetic with
Manual Switching
Remove Manual Switching
and Add new Multi-Level
Switch
$1,000 $374
44 Corridor Lighting -
Type H - Prudential
P1003M42-04SPL-
SA (1 lamp 4'
fixture according to
site visit) Perimeter
11 FLUOR T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$300 $99
46 Similar to Type H
fixture with T12
lights
3 FLUOR T12 4' F40T12 40W
Standard StdElectronic with
Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $33
47 Exterior Lighting -
Type L - Holophane
PARK15AMP27CEB
ZAF1
15 HPS 150 Watt Magnetic with
Daylight Sensor
Replace with 15 LED 80W
Module StdElectronic
$22,500 $3,006
48 Locker Room,
Restrooms - Type I
- Holophane 7200-
4-H1-WB-TB
Perimeter
2 FLUOR (2) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $25
49 Similar to Type H
fixture with T12
lights
3 FLUOR T12 4' F40T12 40W
Standard StdElectronic with
Manual Switching
Replace with 3 FLUOR T8 4'
F32T8 32W Standard
Instant StdElectronic
$300 $17
50 Multipurpose -
Type C - Holophane
BL2C40LHP27RX
6 HPS 400 Watt Magnetic with
Manual Switching
Replace with 6 FLUOR (4)
T8 4' F32T8 32W Standard
(2) Instant StdElectronic
$5,000 $210
56 Storage - Type B2 -
Metalux
MCM240A125LCW
M/ES2
11 FLUOR (2) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 $0
Energy Audit – Energy Analysis and Cost Comparison
AkWarm Commercial Audit Software
Stebbins K-12 School (Tukurngailnguq School)
Page 15
57 Mech/Elec, Janitor,
Storage - Type F -
Metalux
SS240WG/SS-4FT
LCWM/ESE
17 FLUOR (2) T8 4' F32T8 32W
Standard Instant StdElectronic
with Manual Switching
Remove Manual Switching
and Add new Occupancy
Sensor
$200 -$225
Refrigeration
Rank Location Existing Recommended Installed
Cost
Annual
Energy
Savings
1 Walk-in Freezer Walk-in Freezer Add new Seasonal
Shutdown
$1 $1,108
2 Walk in
Refrigerator
Walk in Refrigerator Add new Seasonal
Shutdown
$1 $443
3 Moblie
Refrigerator in
Kitchen
Commercial Refrigerator
(Kitchen)
Add new Seasonal
Shutdown
$1 $222
4 Chest Freezer Chest Freezer Add new Seasonal
Shutdown
$1 $202
5 Refrigerators 3 Refrigerator Add new Seasonal
Shutdown
$1 $100
Other Electrical Equipment
Rank Location Existing Recommended Installed
Cost
Annual
Energy
Savings
Cooking/Clothes Drying
Rank Recommended Installed
Cost
Annual
Energy
Savings
------------------------------------------
AkWarmCalc Ver 2.1.4.2, Energy Lib 3/1/2012
Stebbins Tukurngailnguq K-12 School Comprehensive Energy Audit
56
Appendix C: Existing Plans