HomeMy WebLinkAboutCIRI-ANC-CAEC Benson High School 2012-EEENERGY AUDIT FINAL REPORT
Benson High School
4515 Campbell Airstrip Rd
Anchorage, AK 99517
p (907) 742,2050
AkWarm ID No. CIRI,ANC,CAEC,13
800 F Street
Anchorage, AK 99501
p (907) 276,6664 f (907) 276,5042
Contact: Walter Heins, PE, CCP, CxA, CEA
32215 Lakefront Dr.
Soldotna, Alaska 99669
p (907) 260,5311
Contact: Jerry P. Herring, PE, CEA
Benson High School Final Energy Audit Report
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Contents
I. Executive Summary .................................................................................................................. 1
II. Introduction .............................................................................................................................. 3
III. Energy Audit Process ............................................................................................................. 4
IV. Method of Analysis ................................................................................................................. 5
V. Building Description ................................................................................................................ 6
V.I ARCHITECTURAL DESCRIPTION ............................................................................................................................ 6
V.II MECHANICAL DESCRIPTION ............................................................................................................................... 6
V.III ELECTRICAL DESCRIPTION ................................................................................................................................ 7
VI. Historic Energy Consumption and Cost............................................................................... 9
VI.I ELECTRICAL CONSUMPTION DATA ..................................................................................................................... 9
VI.II NATURAL GAS CONSUMPTION DATA ................................................................................................................ 9
VI.III OVERALL ENERGY CONSUMPTION DATA ......................................................................................................... 9
VII. Equipment Inventory and Photo Survey .......................................................................... 11
VIII. Energy Conservation Measures ....................................................................................... 12
VIII.I SCHOOL ENERGY CONSERVATION MEASURES ............................................................................................... 12
VIII.II ADMINISTRATIVE CONTROLS FOR ENERGY CONSERVATION AND OPTIMIZATION ......................................... 15
Appendices
Appendix A – Energy Benchmark Data
Appendix B – AkWarm Commercial Reports
Appendix C – Major Equipment List
Appendix D – Energy Conservation Measures
Appendix E – Site Survey Photos
Appendix F – Thermographic Photos
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REPORT DISCLAIMER
Privacy
The information contained within this report, including any attachment(s), was produced under contract to Alaska
Housing Finance Corporation (AHFC). IGAs are the property of the State of Alaska, and may be incorporated into
AkWarmC , the Alaska Retrofit Information System (ARIS), or other state and/or public information systems.
AkWarmC is a building energy modeling software developed under contract by AHFC.
Limitations of Study
This energy audit is intended to identify and recommend potential areas of energy savings, estimate the value of the
savings, and provide an opinion of the costs to implement the recommendations. This audit meets the criteria of a
Level 2 Investment Grade Audit (IGA) per the American Society of Heating, Refrigeration, Air,conditioning
Engineers (ASHRAE) and the Association of Energy Engineers (AEE), and is valid for one year. The life of the IGA
may be extended on a case,by,case basis, at the discretion of AHFC. In preparing this report, the preparers acted
with the standard of care prevalent in this region for this type of work. All results are dependent on the quality of
input data provided. Not all data could be verified and no destructive testing or investigations were undertaken.
Some data may have been incomplete.
This report is not intended to be a final design document. Any modifications or changes made to a building to realize
the savings must be designed and implemented by licensed, experienced professionals in their fields. Lighting
upgrades should undergo a thorough lighting analysis to assure that the upgrades will comply with State of Alaska
Statutes as well as Illuminating Engineering Society (IES) recommendations. All liabilities for upgrades, including
but not limited to safety, design, and performance are incumbent upon the professional(s) who prepare the design.
Coffman Engineers, Inc (CEI) and Central Alaska Engineering Company (CAEC) bear no responsibility for work
performed as a result of this report.
Financial ratios may vary from those forecasted due to the uncertainty of the final installed design, configuration,
equipment selected, installation costs, related additional work, or the operating schedules and maintenance provided
by the owner. Furthermore, many ECMs are interactive, so implementation of one ECM may impact the
performance of another ECM. CEI and CAEC accept no liability for financial loss due to ECMs that fail to meet the
forecasted financial ratios.
The economic analyses for the ECMs relating to lighting improvements are based solely on energy savings.
Additional benefits may be realized in reduced maintenance cost, deferred maintenance, and improved lighting
quality. The new generation lighting systems have significantly longer life leading to long term labor savings,
especially in high areas like Gyms and exterior parking lots. Lighting upgrades displace re,lamping costs for any
fixtures whose lamps would otherwise be nearing the end of their lifecycle. This reduces maintenance costs for 3,7
years after the upgrade. An overall improvement in lighting quality, quantified by numerous studies, improves the
performance of students and workers in the built environment. New lighting systems can be designed to address all
of the above benefits.
US Government Disclaimer
This material is based upon work supported by the Department of Energy under Award Number DE,EE0000095.
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither
the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or
implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any
information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned
rights. Reference herein to any specific commercial product, process, or service by trade name, trademark,
manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring
by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not
necessarily state or reflect those of the United States Government or any agency thereof.
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I. Executive Summary
This report presents the findings of an energy audit conducted at Benson High School as part of a contract
for:
Alaska Housing Finance Corporation
Contact: Rebekah Luhrs
4300 Boniface Parkway
Anchorage, AK 99510
Email: rluhrs@ahfc.us
Anchorage School District
Contact: Calvin Mundt
1301 Labar Street
Anchorage, AK 99517
Email: mundt_calvin@asdk12.org
This audit was performed using American Recovery and Reinvestment Act (ARRA) funds to promote the
use of innovation and technology to solve energy and environmental problems in a way that improves the
State of Alaska’s economy. This can be achieved through the wiser and more efficient use of energy.
The average January 2009,December 2010 documented annual utility costs at this facility are as follows:
Electricity $42,206
Natural Gas $20,405
Total $62,610
January 2009,December 2010 Energy Utilization Index (EUI) = 112.2 kBtu/sf
January 2009,December 2010 Energy Cost Index = 2.14 $/sf
Energy Conservation Measures (ECMs) calculated to be cost effective are shown below in the Executive
Summary Table with the energy analyst’s best opinion of probable cost, savings, and investment returns.
Be aware that the measures are not additive because of the interrelation of several of the measures. The
cost of each measure for this level of auditing is ± 30% until detailed engineering, specifications, and hard
proposals are obtained. See section VIII for detailed descriptions of all cost effective ECMs.
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Executive Summary – ECMs
Benson High School (BHS)
Rank Feature Recommendation Annual
Energy
Savings
Installed
Cost
SIR Payback
(Years)
BHS,0a Refrigerators Replace residential &
light commercial
refrigerators/freezers
older than 5 years old
, , , <10
BHS,1 Setback
Thermostat: All
Building Spaces
Implement a Heating
Temperature
Unoccupied Setback to
60.0 deg F for all
building spaces.
$4,423 $792 71.0 0.2
BHS,2 Lighting:
Exterior: All
lighting Types
Provide time clock
control of all exterior
lighting.
$2,051 $1,000 31.6 0.5
BHS,3 Other Electrical:
Vending
Machines
Add new motion
sensing controls
$1,500 $844 3.59 1.8
BHS,4b HVAC And
DHW
Upgrade existing
pumps with premium
efficiency pumps
$272 $1,290 3.19 4.7
BHS,5 Lighting: Duct
Chase Lighting
Replace with FLUOR
(14) CFL, A Lamp 9W
$62 $140 2.83 2.3
BHS,6 Lighting:
Exterior Type
HC,HE,HH
Replace with 11 LED
20W Module
StdElectronic
$292 $2,200 2.04 7.5
BHS,7 Lighting: Gym
Lighting
Add new Multi,Level
Switch
$155 $1,500 1.57 9.6
Notes:
a Due to advances in refrigerators in the previous 5 years, new Energy Star refrigerators are much more efficient and
result in viable energy savings.
b.This item is intended to be implemented as HVAC pumps burn out and require replacement, when expenses must
be made due to equipment failure. This is the cost difference between standard efficiency motors and high efficiency
motors for all HVAC pumps.
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II. Introduction
This energy audit was conducted at Benson High School (BHS) for AHFC and the Anchorage School
District. The school is an approximately 29,284 square foot (sf) campus that includes classrooms, locker
rooms, restrooms, administrative offices, and a multipurpose room. The location of the school is shown in
the following regional and overhead images. The energy audit was conducted in order to evaluate areas
and equipment where energy savings can be realized. The savings are then compared to a baseline and
evaluated for reasonable project financial ratios and payback.
Anchorage, Alaska – Google Maps
Benson High School – Google Maps
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III. Energy Audit Process
Prior to visiting the school, the first task was to collect and review two years of utility data for electricity
and natural gas usage. This information was used to analyze operational characteristics, calculate energy
benchmarks for comparison to industry averages, estimate savings potential and establish a baseline to
monitor the effectiveness of implemented energy conservation measures. A spreadsheet was used to enter,
sum, and calculate benchmarks and to graph energy use information (see Appendix A). The primary
benchmark calculation used for comparison and baseline data is the Energy Utilization Index, or EUI (see
Section VI).
After gathering the utility data and calculating the EUI, the next step in the audit process was to review
the architectural and engineering drawings to develop a building profile which documented building age,
type, usage, and major energy consuming equipment or systems such as lighting, Heating, Ventilating,
and Air Conditioning (HVAC), water heating, refrigeration, snow,melt, and etc. The building profile is
utilized to generate, and answer, all possible questions regarding the facility’s energy usage. These
questions were then compared to the energy usage profiles developed during the utility data gathering
step. After this information was gathered, the next step in the process was to conduct a site survey.
A site survey was completed on November 14, 2011. Time was spent inspecting the building systems that
impact energy consumption and answering questions from the preliminary review of the school. The on,
site contact during the investigation was Mr. Bob Halpin of the ASD Facilities Department1. The
following information was also collected while on site: occupancy schedules, O&M practices, building
energy management program, and other information that has an impact on energy consumption.
The following energy audit includes an evaluation of the information gathered, the researching of possible
conservation opportunities, organizing the energy audit into a comprehensive report, and making ECM
recommendations for mechanical, electrical, and building envelope improvements.
1 Mr. Bob Halpin, (907) 632,2884 (mobile), (907) 348,5212 (office)
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IV. Method of Analysis
Having completed the preliminary energy audit tasks, Coffman Engineers, Inc., (CEI) conducted a site
survey. The site survey provides critical input in deciphering where energy savings opportunities exist
within a facility. The audit team from CEI walked the entire site to inventory and investigate the building
envelope and major equipment, including: HVAC, water heating, lighting, and equipment located in
shops, kitchens, offices, and classrooms. An understanding of how the equipment is used is determined
during the site survey.
The collected data was entered into AkWarm Commercial™ software, an energy calculating program for
buildings. The data was processed by AkWarm to model a baseline from which ECMs could be
considered. The model was compared to actual utility costs to ensure the quality of the baseline and
proposed energy modeling performed by AkWarm. The recommended ECMs focus on the building
envelope, HVAC, lighting, water heating, and other electrical measures that will reduce annual energy
consumption.
ECMs are evaluated based on building use and processes, local climate conditions, building construction
type, function, operational schedule, existing conditions, and foreseen future plans. When new equipment
is proposed, energy consumption is calculated based on the manufacturer’s cataloged information. Energy
savings are calculated by AkWarm.
Implementation of more than one ECM often affects the savings of other ECMs. The savings may in
some cases be relatively higher for an ECM implemented individually than when that ECM is just one of
multiple recommended ECMs. For example, implementing reduced operating schedules of inefficient
lighting systems may result in a given savings. Also implementing a more efficient lighting system will
add to the savings, but less than the efficient lighting would alone because there is less energy to be saved
when the lights are on a reduced operating schedule. Thus, if multiple ECM’s are recommended, the
combined savings are calculated and identified appropriately in groups.
In Appendix D, Energy Conservation Measures, the simple lifetime calculation is shown for each ECM,
which is based on the typical life of the equipment being replaced or altered. The energy savings are
extrapolated throughout the simple lifetime of the ECM. The total energy savings is calculated as the total
lifetime multiplied by the yearly energy savings.
The cost savings and installation costs are used to calculate simple payback2 and the Savings to
Investment Ratio3 (SIR). These are listed in Appendix D and summarized in the Executive Summary
Table of this report. The SIR is calculated as a ratio by dividing the break even cost by the initial installed
cost. Cost savings is calculated based on the historical energy costs for the building. Installation costs
include labor and equipment to evaluate the initial investment required to implement an ECM. These are
applied to each recommendation with simple paybacks calculated. The energy analyst’s opinions of
probable cost are garnered from RS Means Cost Data, other industry publications, and local contractors
and suppliers. In addition, where applicable, maintenance cost savings are estimated and applied to the net
savings.
2 The simple payback is based on the years that it takes for the net savings to payback the net installation cost (Cost
divided by Savings).
3 Savings to Investment Ratio (SIR): Break Even Cost divided by initial installed cost, where Break,Even Cost is
how much can be spent and still have the measure be cost effective; it equals the Present Value (PV) of Savings over
the life of the measure minus PV of maintenance costs.
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V. Building Description
Benson High School is a two story building consisting of a multipurpose room, classroom and office
spaces, and supporting utility and storage spaces. The school was built in 1991 and has had an HVAC
upgrade in 2003, a roof upgrade in 2004, and a lighting replacement in 2009. Benson High School is
occupied by approximately 160 people from 6:30 am to 4:30 pm weekdays from August through May.
Most of the building, except the main office and maintenance areas, is unoccupied and shut down from
June to July.
V.I Architectural Description
Wall, floor, and roof construction details were obtained from the architectural drawings. The exterior
walls of the school were constructed with 2”x6” wood studs on 24” centers, R,19 fiberglass batt
insulation, plywood sheathing and beveled wood siding for an estimated composite R,value of R,16.9. In
most locations, the lower three feet of the exterior wall has stucco siding. Exterior walls throughout most
of the building are 11’ high, except in areas such as multipurpose and mechanical spaces, where the walls
are approximately 21’ high. Architectural drawings show there is approximately 13,500 sf of exterior
above grade wall area.
Floor construction for the school is 4” thick concrete slab,on,grade. The perimeter of the slab has 2” rigid
edge insulation (R,10) that extends to 4 feet below grade, along the foundation wall. There is a total of
27,044 sf of slab,on,grade floor area which does not include the approximately 2,240 sf second floor fan
room.
The roof is gabled with multiple dormers and consists of plywood sheathing, SAM waterproofing, asphalt
shingles and pre,finished 24 gage metal flashing that extends 3 inches over the eave face. The estimated
composite R,value for the roof is R,21.3. The soffit and attic are vented to allow for a cold roof
construction. The roof trusses have 24” centers and are assumed to be filled with R,19 fiberglass batts.
The valleys and eaves are lined with 6”x72” PVC coated, flat panel heat trace to provide anti,icing
protection. New ridge vents were installed on the roof in 1998. An analysis of the construction drawings
shows that there is approximately 29,072 sf of roof area for the school.
Typical window construction for the school consists of triple pane, low,e, clear glass with a 1/2” air filled
pane space and an aluminum frame without a thermal break which provide an R,value of R,1.6.
Typically, triple pane windows provide an R,value close to R,3.0 when installed in vinyl frames, however
aluminum frames have high heat losses. The school entrance, located on the building’s south face,
contains a double pane, low,e, clear glass window with a 1/2” air space between the panes in a similar
frame. This window is heavily shaded and provides an R,value of R,1.4. The school’s window area for all
windows facing south is approximately 770 sf and all other window areas for the school total
approximately 873 sf.
There are six windowless exterior man doors in the school that are hollow metal with insulated cores
providing an effective R,value of R,5.3. There are eight entryway doors that are hollow metal with
insulated cores and half lite windows (R,3.3) and two exterior doors to the dock area that are hollow
metal with insulated cores and a half lite window (R,2.2). All of the doors were installed during the
original construction, have weather stripping in fair condition, and are approximately 20 years old.
V.II Mechanical Description
The school is heated using two Weil,McLain BE,688 gas,fired, cast,iron, sectional boilers, each supplied
with a Gordon Piatt R8.2,G power burner. The boilers and burners were installed in 1991 and have DDC
controls. Each boiler has a 1,703 MBH input rating and operates year round. A 2HP Bell and Gossett
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circulation pump is provided for each boiler and hot water is circulated to a plate and frame type heat
exchanger located in the mechanical room before being recirculated back to the boilers.
An 80 gallon indirect water heater is located in the mechanical room and is used to provide domestic hot
water for the school and kitchen area. The domestic hot water is recirculated with a Grundfos pump that
does not have DDC control and therefore operates continuously unless manually turned off.
No mechanical cooling is provided for any equipment in the building. There are two air handling units
(AHU) located in the fan room which provide tempered air using hydronic coils. The multipurpose room
is served by AHU,2, a McQuay modular air handler equipped with a 5 HP fan. The rest of the school is
served by AHU,1, also a McQuay modular air handler, equipped with a 40 HP fan with a variable
frequency drive. Other fans in service include exhaust fans serving the restrooms, a combustion air fan
serving the boiler room, and a return fan serving the same areas as AHU,1. Additionally, a kitchen hood
and exhaust fan are installed, but are rarely used since no food is prepared at Benson. Large sections of
the supply duct work have been damaged resulting in a high likelihood of increased leakage.
The school’s building energy management and control system was originally pneumatically controlled.
All existing air handling systems and heat generation system pneumatic controls were replaced with a
Siemens Direct Digital Control system in 2003.
V.III Electrical Description
Benson High School is served by a 1200A, 208V, 3,phase, 4,wire, underground service. The electric
utility is Chugach Electric Association. The school also has a standby, reciprocating diesel generator. The
school building had a major lighting upgrade in 2009.
The classrooms and teacher workroom are illuminated by 2,foot by 4,foot recessed volumetric troffers
equipped with two 32 watt (W) T,8 fluorescent lamps and step dimming electronic ballasts. The
classrooms also have limited numbers of 1,foot by 4,foot recessed lensed luminaires equipped with two
32W T,8 fluorescent lamps and non,dimming electronic ballasts. All classrooms are equipped with bi,
level switching and occupancy sensors that turn all lights off when no occupancy is detected.
Corridors and circulation areas are illuminated by 2,foot by 4,foot recessed and surface mounted lensed
troffers and step dimming electronic ballasts. The wider circulation areas also have a 6" diameter recessed
down lights equipped with two 26W quad tube compact fluorescent lamps. The corridors are equipped
with bi,level switching and occupancy sensors that dim the lights to 50% when no occupancy is detected.
The corridor lighting is turned off by the Direct Digital Control system when the security system is
armed. There are approximately (12) fixtures connected as night lights.
The office spaces are illuminated by 2,foot by 4,foot recessed volumetric troffers equipped with two 32W
T,8 fluorescent lamps and step dimming electronic ballasts. The offices are equipped with bi,level
switching and occupancy sensors that turn all lights off when no occupancy is detected. The main office
has a daylight harvesting system that switches off a portion of the lights when there is sufficient natural
lighting.
The multipurpose room is illuminated by high,bay fluorescent fixtures equipped with four 54W T,5HO
fluorescent lamps and electronic ballasts. The multipurpose room has manual keyed switches that control
two separate lighting zones.
Restrooms, utility rooms, and storage spaces are typical illuminated by fluorescent fixtures equipped with
32W T,8 fluorescent lamps and step dimming electronic ballasts. Occupancy sensors have been installed
in all spaces where they will not create a safety hazard.
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Lighting levels throughout the school are consistent with current IESNA illumination standards.
Exterior lighting is provided by a combination of high pressure sodium (HPS) and light emitting diode
(LED) sources. There are (11) 400W HPS pole mounted "shoebox" type area lighters illuminating the
parking lot and driveway. There are (13) illuminated bollards near the main entry with 70W HPS sources.
There are (4) 100W HPS pendant mounted cylindrical downlight fixtures over the main entry. There are
(7) 30W LED wallpacks around the perimeter of the building. There are (8) surface mounted 100W HPS
fixtures over the secondary entrances and on the loading dock area. All exterior lighting is controlled by
contactors located in the main electrical room which are controlled by the DDC system based on the
signal from a central photocell.
Other electricity,using equipment not previously described in the mechanical or electrical sections include
a commercial reach,in freezer, a commercial reach,in refrigerator, a microwave and other kitchen
equipment, and various user equipment such as projectors, computers, printers, and a laminator (which is
turned off when not in use).
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VI. Historic Energy Consumption and Cost
Tables provided in Appendix A, Energy Benchmark Data Report, represent the electric and natural gas
energy usage for the school from January 2009 to December 2010. Chugach Electric provides the
electricity and Enstar Natural Gas provides the natural gas to the school. Both utility companies bill the
school district using a commercial rate schedule. The actual utility bills were not provided to be able to
verify the data received to assure 100 percent accuracy of the data.
The AkWarm model of the school was built to match the school’s average annual electric and natural gas
consumption so that a realistic model could be created. The monthly energy consumption of the AkWarm
model matches the actual average monthly consumption of the school within 25%, which is adequate for
this level of modeling. Overall, the energy consumption trends of the AkWarm model and the actual
facility match appropriately. Graphical representations of the monthly energy consumption are included
in Appendix A.
VI.I Electrical Consumption Data
The electric utility costs consist of several components: a fixed monthly customer charge, an energy usage
charge, fuel surcharge, taxes, and a demand charge. The energy usage and fuel surcharge are based on the
customer's usage as measured in kilowatt,hours (kWh). The usage (kWh) is determined by load wattage
divided by 1,000, times hours running. For example, a 1,000 watt space heater operating for one hour will
use 1 kWh of electricity as would ten, 100 watt lamps operating for one hour, or one 100W lamp
operating for 10 hours. One kWh is equivalent to 3,413 BTU. Demand charges are based on the
maximum number of kilowatts used averaged over a 15 minute period. Utility data used in this report
reflects the historical data provided for the building in a summarized format.
VI.II Natural Gas Consumption Data
The natural gas supplier bills for consumption in CCF of natural gas, where one CCF equals 100 cubic
feet of natural gas. The average heating value of natural gas is 1,000 BTUs per cubic foot, making 1 CCF
equal to 100,000 BTUs or 1 Therm.
VI.III Overall Energy Consumption Data
The overall cost for energy use is calculated by dividing the total cost by the total usage. Based on the
electric and natural gas utility data provided, the average cost for the energy and consumption calculations
at the surveyed facility are summarized in the table below.
Energy Cost and Consumption Data
2009 2010 Average
Electric 0.14 $/kWh 0.11 $/kWh 0.12 $/kWh
Natural Gas 1.03 $/CCF 0.93 $/CCF 0.97 $/CCF
Total Cost $65,458 $59,763 $62,611
ECI 2.24 $/sf 2.04 $/sf 2.14 $/sf
Electric EUI 39.1 kBtu/sf 42.4 kBtu/sf 40.7 kBtu/sf
Natural Gas EUI 66.9 kBtu/sf 76.1 kBtu/sf 71.5 kBtu/sf
Building EUI 106.0 kBtu/sf 118.5 kBtu/sf 112.2 kBtu/sf
The Energy Cost Index (ECI) is derived by dividing the annual cost by the building square footage. The
building square footage was calculated to be approximately 29,284 square feet.
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The annual EUI is expressed in Thousands of British Thermal Units per Square Foot (kBtu/sf) and can be
used to compare energy consumption of similar building types or to track consumption from year to year
in the same building. The EUI is calculated by converting annual consumption of all fuels used to Btu’s
and then dividing by the area (gross conditioned square footage) of the building. EUI is a good indicator
of the relative potential for energy savings. A comparatively low EUI indicates less potential for large
energy savings. Building architectural, mechanical, and electrical drawings were obtained and utilized to
calculate and verify the gross area of the facility. The gross area was confirmed on the physical site
investigation.
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VII. Equipment Inventory and Photo Survey
Following the completion of the field survey a detailed equipment list was created and is attached as
Appendix C. The major equipment listed are considered to be the major energy consuming equipment in
the building whose replacement could yield substantial energy savings.
An approximate age was assigned to the equipment if a manufactured date was not shown on the
equipment’s nameplate. As listed in the 2011 ASHRAE Handbook for HVAC Applications, Chapter 37,
Table 4, the service life for the equipment along with the remaining useful life in accordance to the
ASHRAE standard are also noted in the equipment list.
Where there are zero (0) years remaining in the estimated useful life of a piece of equipment, this is an
indication that maintenance costs are likely on the rise and more efficient replacement equipment is
available which will lower the operating costs of the unit. Maintenance costs should also fall with the
replacement.
Additionally, photos of various equipment and the building construction were taken during the site
survey. Several photos are included in Appendix E.
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VIII. Energy Conservation Measures
VIII.I School Energy Conservation Measures
The following ECMs described here have been calculated by AkWarm Commercial and considered by the
energy audit team as viable projects. ECMs provided below are considered to have viable financial ratios
(SIR>1) or to add value to the building or building operational profiles. For a full list of ECMs considered
and calculated by the energy audit team, including ECMs not recommended at this time, please see
Appendix D.
ECM# BHS80 – Replace residential & light commercial refrigerators/freezers older than 5 years old
Annual Energy Savings Installed Cost SIR Payback (years)
, , , <10 years
Due to advances in refrigerators in the previous five years, new Energy Star residential,type and light
commercial,type refrigerators and freezers are much more efficient and result in viable energy savings.
Built,in refrigerators and freezers should be evaluated independently. Replacing existing refrigerators,
which are older than five years old, with new energy star models will typically have paybacks of less than
10 years.
ECM# BHS81 – Setback Thermostat in all building spaces
Annual Energy Savings Installed Cost SIR Payback (years)
$4,423 $792 71.0 0.2
Significant energy savings exist by reducing the room temperature of the building spaces during
unoccupied times. Reducing the temperature to 60F during unoccupied times will lower the heat load of
the building and reduce natural gas consumption. Since the school’s thermostats are already connected to
the DDC system, the cost of this ECM only includes the time required to program a night setback which
can be performed by maintenance personnel. This ECM is a compilation of items 2, 3, and 4 as modeled
in AkWarm which are intended to be implemented concurrently. Details of the individual items are shown
in Appendix D.
ECM # BHS82– Provide time clock control of all exterior lighting
Annual Energy Savings Installed Cost SIR Payback (years)
$2,051 $1,000 31.6 0.5
The exterior lighting at this site consists of (11) 400W HPS pole mounted "shoebox" type area lighters,
(13) 70W HPS illuminated bollards, (4) 100W HPS pendant mounted cylindrical downlight fixtures, (7)
30W LED wallpacks, and (8) surface mounted 100W HPS fixtures. Altogether, the exterior lighting
system uses over 7 kW continuously or 84 kWh during a 12 hour night. All of the exterior lighting is
controlled by contactors mounted in the main electrical room which are controlled by a signal from the
DDC system that turns the lights on based on input from a central photocell. This ECM recommends
programming the DDC control to accept input from the photocell as well as from a time clock. For
modeling purposes, it was assumed that the lights are on for an average of 12 hours per night. The run
time of the exterior lighting can be reduced by six hours by programming the DDC system to turn on the
exterior lighting when it is dark and not between the hours of midnight and 6 am. Further savings can be
achieved by turning off the exterior lighting seasonally when school is not in session. A minimum amount
of exterior lighting required for safety can be left on by rewiring to move some lighting circuits to the
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spare lighting contactor and bringing a second control line to the light contactors from the DDC system.
There are potential safety, liability, and operational issues that must be addressed before reducing any
exterior lighting. This ECM is a compilation of items 1, 5, 6, and 8 as modeled AkWarm which are
intended to be implemented concurrently. Details of the individual items are shown in Appendix D.
ECM # BHS83 – Provide motion sensing control of vending machines
Annual Energy Savings Installed Cost SIR Payback (years)
$1,500 $844 3.59 1.8
This school has three refrigerated drink machines, two snack machines, and one change machine that are
on continually. The vending machines are located in two locations with four machines in the lobby and
two in corridor 103, near the multipurpose room. The nameplate data on these machines was not
available. For modeling purposes, industry average loads of 400W for refrigerated drink machines and
85W for the snack and change machines were used. This measure includes installing Vending Miser® or
similar motion sensing controls at both locations. This system consists of occupancy sensors and ambient
temperature sensors that turn on non,refrigerated vending machines only when a person is detected and
turns on refrigerated vending machines when a person is detected or as needed to maintain product
temperature. In K,12 settings, typical energy savings range from 25%,65%. For modeling purposes, a
savings of 50% was assumed. This ECM is a compilation of items 7 and 13 as modeled in AkWarm
which are intended to be implemented concurrently. Details of individual items are shown in Appendix D.
ECM # BHS84 – Upgrade existing pumps with NEMA premium efficiency motors
Annual Energy Savings Installed Cost SIR Payback (years)
$272 $1,290 3.19 4.7
New, high efficiency pump motors have reduced electrical demands which create significant energy
savings for larger horsepower (HP) pumps. The existing boiler circulation pumps, P,1A, P,1B, P,2A, and
P,2B, have 10 HP and 3 HP motors respectively. The pumps were installed in 2003 and have motors with
an estimated 10 years of remaining service life. Replacing these pump motors while the existing motors
are still functional will result in a $19,890 replacement cost with an annual energy savings of $448 and a
simple payback of 44.4 years. However, upgrading these pump motors to high efficiency motors when the
existing motors are in need of repair will offer a more reasonable payback because the marginal cost of
the high efficiency pump motor over the standard efficiency motor replacement is only a $1,290 repair
cost. This ECM item was modeled with a separate AkWarm model and as a result the item is not an
additive measure in AkWarm. It is therefore not included in the final cost savings total in the final
AkWarm model in Appendix D.
ECM # BHS85–Relamp duct chase lighting with CFL
Annual Energy Savings Installed Cost SIR Payback (years)
$62 $140 2.83 2.3
The duct chase is a normally unoccupied space on the 2nd floor that is used for inspection and
maintenance of mechanical systems. It is illuminated by approximately (14) A,base lamp holders with
60W incandescent lamps. Several have been replaced with CFL lamps. This ECM would replace the
remaining incandescent lamps with 9W CFL lamps. Refer to item 10 in Appendix D for more
information.
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ECM# BHS86 8 Upgrade building mounted exterior HPS lighting to LED
Annual Energy Savings Installed Cost SIR Payback (years)
$292 $2,200 2.04 7.5
The building mounted exterior HPS lighting at the school consists of four 100W HPS pendant mounted
cylindrical downlight fixtures and eight surface mounted 100W HPS fixtures. The wallpack fixtures have
already been replaced with LED fixtures. This ECM would replace the 100W HPS fixtures with 20W
LED fixtures and would utilize existing wiring. Implementing this ECM reduces the benefits of ECM
#BHS,4. Refer to item 11 in Appendix D for more information on this ECM. The replacement of the
parking lot lighting and bollard lighting with LED fixtures was also modeled, but it was not shown to be
cost effective based solely on energy savings.
ECM# BHS87 8 Provide bi8level switching in multipurpose room
Annual Energy Savings Installed Cost SIR Payback (years)
$155 $1,500 1.57 9.6
The multipurpose room is illuminated by high,bay fluorescent fixtures equipped with four 54W T,5HO
fluorescent lamps and electronic ballasts and several skylights. The multipurpose room has two manual
keyed switches that control two separate lighting zones. This measure would rewire the gym lighting and
provide two additional switches, for a total of four. Each switch would control two lamps in each fixture
in one zone. This would give users the option of reducing lighting levels and energy use to 50% if the
activity in the room does not require higher lighting levels or if sufficient natural light is available. See
item 12 in Appendix D for more information.
ECM # BHS88 – Replace water heater with a dual water8to8water/electric heater to allow for
seasonal boiler shutoff
Annual Energy Savings Installed Cost SIR Payback (years)
$125 $6,500 0.29 52.1
Though this ECM does not have a SIR above one according to the AkWarm model, it should still be
considered as an energy conservation measure. Significant energy savings can be gained by turning off
the boilers during June and July when the school is minimally occupied and summer temperatures do not
require building heat. The current indirect water heater relies on the boilers to supply domestic hot water.
New water heater technologies allow for dual,energy sources to provide emergency back up or seasonal
boiler operation. Due to the limitations of the AkWarm software, this ECM was not modeled within
AkWarm. Energy savings and project financial ratios were evaluated using documented energy usage,
average energy costs, and manufacturer’s technical specifications for a 140 gallon AO Smith DVE,140,
24 with a 24 kilowatt electric element.
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VIII.II Administrative Controls for Energy Conservation and Optimization
While the intent of many energy conservation measures is to increase the efficiency of fuel,burning and
electrical equipment, an important factor of energy consumption lies in the operational profiles which
control the equipment usage. Such profiles can be managed by administrative controls and departmental
leadership. They determine how and when fuel,burning and electrical equipment are used, and therefore
have a greater impact on energy savings potential than simply equipment upgrades alone. Significant
energy cost savings can be realized when ECMs are combined with efficient,minded operational profiles.
Operational profiles may be outlined by organization policy or developed naturally or historically. These
profiles include, but are not limited to: operating schedules, equipment setpoints and control strategies,
maintenance schedules, and site and equipment selection.
Optimization of operational profiles can be accomplished by numerous methods so long as the intent is
reduction in energy,using equipment runtime. Due to the numerous methods of optimization, energy cost
savings solely as a result of operational optimization are difficult to predict. Quantification, however, is
easy to accomplish by metering energy usage during and/or after implementation of energy,saving
operational profiles and ECMs. Shown below are some examples which have proven successful for other
organizations.
Optimization of site selection includes scheduling and location of events. If several buildings in a given
neighborhood are all lightly used after regularly occupied hours, energy savings can be found when after,
hours events are consolidated and held within the most energy efficient buildings available for use. As a
result, unoccupied buildings could be shut down to the greatest extent possible to reduce energy
consumption.
Two operational behaviors which can be combined with equipment upgrades are operating schedules and
equipment control strategies including setpoints. Occupancy and daylight sensors can be programmed to
automatically shut off or dim lighting when rooms are unoccupied or sufficiently lit from the sun.
Operating schedules can be optimized to run equipment only during regular or high,occupancy periods.
Also, through a central control system, or with digital programmable thermostats, temperature setpoints
can be reduced during low,occupancy hours to maximize savings. In addition, sporadically used
equipment can be shut down during unoccupied hours to further save energy. In general, having
equipment operating in areas where no occupants are present is inefficient, and presents an opportunity
for energy savings.
Operational profiles can also be implemented to take advantage of no, or low,cost ECMs. Examples
include heating plant optimizations (boiler section cleaning, boiler flush,through cleaning) and tighter
controls of equipment setbacks and shutdowns (unoccupied zones equipment shutdown, easier access to
and finer control of equipment for after,hours control). In a large facility management program,
implementation of these measures across many or all sites will realize dramatic savings due to the
quantity of equipment involved.
Changes to building operational profiles can only be realized while simultaneously addressing health,
safety, user comfort, and user requirements first. It is impractical to expect users to occupy a building or
implement operational behaviors which do not meet such considerations. That said, it is quite practical for
management groups to implement administrative controls which reduce losses brought about by excess
and sub,optimum usage.
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Appendix A
Energy Benchmark Data
First Name Last Name Middle Name Phone
Steven Golab 348-5132
State Zip
AK
Monday-Friday Saturday Sunday Holidays
7:00-4:00
Average # of
Occupants
During
Primary
Operating
Hours
Golab_Steven@asdk12.org
Anchorage
Contact Person
City
Anchorage
Mailing Address
99517
Email
4515 Campbell Airstrip Rd
Facility Owned By Date
07/22/11Municipal Government/Subdivision
REAL Preliminary Benchmark Data Form
PART I – FACILITY INFORMATION
Facility Owner
MOA
Year Built
1991
Building Name/ Identifier Building Usage Building Square Footage
Facility Zip
261,500
Benson High School Education - K - 12 29,284
Facility Address
Building Type
Mixed
Community Population
Facility City
Renovations
Date
PART II – ENERGY SOURCES
Heating Oil Electricity Natural Gas Propane Wood Coal
$ /gallon $ / kWh $ / CCF $ / gal $ / cord $ / ton
Other energy
sources?
Describe
2. Provide utilities bills for the most recent two-year period for each energy source you use.
1. Please check every energy source you use in the table below. If known, please enter the base rate you pay
for the energy source.
Details
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Benson High School
Buiding Size Input (sf) =29,284
2009 Natural Gas Consumption (Therms)19,599.00
2009 Natural Gas Cost ($)20,095
2009 Electric Consumption (kWh)335,079
2009 Electric Cost ($)45,363
2009 Total Energy Use (kBtu)3,103,525
2009 Total Energy Cost ($)65,458
Annual Energy Use Intensity (EUI)
2009 Natural Gas (kBtu/sf) 66.9
2009 Electricity (kBtu/sf)39.1
2009 Energy Utilization Index (kBtu/sf)106.0
Annual Energy Cost Index (ECI)
2009 Natural Gas Cost Index ($/sf)0.69
2009 Electric Cost Index ($/sf)1.55
2009 Energy Cost Index ($/sf)2.24
2010 Natural Gas Consumption (Therms)22,294.00
2010 Natural Gas Cost ($)20,715
2010 Electric Consumption (kWh)363,528
2010 Electric Cost ($)39,048
2010 Total Energy Use (kBtu)3,470,121
2010 Total Energy Cost ($)59,763
Annual Energy Use Intensity (EUI)
2010 Natural Gas (kBtu/sf)76.1
2010 Electricity (kBtu/sf)42.4
2010 Energy Utilization Index (kBtu/sf)118.5
Annual Energy Cost Index (ECI)
2010 Natural Gas Cost Index ($/sf)0.71
2010 Electric Cost Index ($/sf)1.33
2010 Energy Cost Index ($/sf)2.04
Note:
1 kWh = 3,413 Btu's
1 Therm = 100,000 Btu's
1 CF ≈ 1,000 Btu's
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Benson High SchoolNatural GasBtus/CCF =100,000Provider Meter # Month Start Date End Date Billing Days Consumption (CCF) Consumption (Therms) Demand Use Natural Gas Cost ($) Unit Cost ($/Therm) Demand Cost ($)Enstar NGC7757 Jan-09 01/13/09 02/13/09 31 29362936$3,005$1.02Enstar NGC7757 Feb-09 02/13/09 03/13/092819601960$2,026$1.03Enstar NGC7757 Mar-09 03/13/09 04/15/093317271727$1,796$1.04Enstar NGC7757 Apr-09 04/15/09 05/14/092913181318$1,383$1.05Enstar NGC7757 May-09 05/14/09 06/16/0933876876$942$1.08Enstar NGC7757 Jul-09 06/16/09 07/16/0930658658$720$1.09Enstar NGC7757 Aug-09 07/16/09 08/17/0932627627$694$1.11Enstar NGC7757 Aug-09 08/17/09 09/15/0929726726$779$1.07Enstar NGC7757 Sep-09 09/15/09 10/14/092910221022$1,068$1.05Enstar NGC7757 Oct-09 10/14/09 11/13/093019241924$2,000$1.04Enstar NGC7757 Nov-09 11/13/09 12/10/092727462746$2,850$1.04Enstar NGC7757 Dec-09 12/10/09 01/13/103430793079$2,832$0.92Enstar NGC7757 Jan-10 01/13/10 02/12/10 30 28352835$2,443$0.86Enstar NGC7757 Feb-10 02/12/10 03/15/103125382538$2,187$0.86Enstar NGC7757 Mar-10 03/15/10 04/16/103225512551$2,210$0.87Enstar NGC7757 Apr-10 04/16/10 05/13/102720152015$1,760$0.87Enstar NGC7757 May-10 05/13/10 06/14/103214631463$1,282$0.88Enstar NGC7757 Jun-10 06/14/10 07/14/1030829829$731$0.88Enstar NGC7757 Jul-10 07/14/10 08/16/1033793793$845$1.07Enstar NGC7757 Aug-10 08/16/10 09/15/103010651065$1,208$1.13Enstar NGC7757 Sep-10 09/15/10 10/14/102913751375$1,467$1.07Enstar NGC7757 Oct-10 10/14/10 11/11/102819541954$1,957$1.00Enstar NGC7757 Nov-10 11/11/10 12/10/102920842084$2,046$0.98Enstar NGC7757 Dec-10 12/10/10 01/18/113927922792$2,579$0.92Jan - 09 to Dec - 09 total:19,59919,5990$20,095$0Jan - 10 to Dec - 10 total:22,29422,2940$20,715$0$1.03$0.93Jan - 09 to Dec - 09 avg:Jan - 10 to Dec - 10 avg:Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
$2,000 $2,500 $3,000 $3,500 2000250030003500Natural Gas Cost ($)Natural Gas Consumption (Therms)Benson High School - Natural Gas Consumption (Therms) vs. Natural Gas Cost ($)Natural Gas Consumption (Therms)$0 $500 $1,000 $1,500 050010001500Jan-09 Mar-09 May-09 Jul-09 Sep-09 Nov-09 Jan-10 Mar-10 May-10 Jul-10 Sep-10 Nov-10Natural Gas Cost ($)Natural Gas Consumption (Therms)Date (Mon - Yr)(Therms)Natural Gas Cost ($)Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Benson High SchoolElectricityBtus/kWh =3,413Provider Customer # Month Start Date End Date Billing Days Consumption (kWh) Consumption (Therms) Demand Use Electric Cost ($) Unit Cost ($/kWh) Demand Cost ($)CEA 1839-27839800 Jan-09 1/7/2009 2/6/200930329651,125104 $5,173$0.160CEA 1839-27839800 Feb-09 2/6/2009 3/10/20093227946954102 $4,375$0.160CEA 1839-27839800 Mar-09 3/10/2009 4/8/200929296781,013102 $4,510$0.150CEA 1839-27839800 Apr-09 4/8/2009 5/8/2009302824296494 $4,209$0.150CEA 1839-27839800 May-09 5/8/2009 6/8/2009312341679994 $3,642$0.160CEA 1839-27839800 Jun-09 6/8/2009 7/8/2009301386447390 $2,087$0.150CEA 1839-27839800 Jul-09 7/8/2009 8/6/2009291483150664 $2,128$0.140CEA 1839-27839800 Aug-09 8/6/2009 9/4/2009292142373174 $2,871$0.130CEA 1839-27839800 Sep-09 9/4/2009 10/6/2009322334579791 $3,048$0.130CEA 1839-27839800 Oct-09 10/6/2009 11/5/200930376431,28593 $4,379$0.120CEA 1839-27839800 Nov-09 11/5/2009 12/7/200932404621,38194 $4,553$0.110CEA 1839-27839800 Dec-09 12/7/2009 1/5/201029412641,40894 $4,388$0.110 CEA 1839-27839800 Jan-10 1/5/2010 2/5/201031425851,45396 $4,355$0.100CEA 1839-27839800 Feb-10 2/5/2010 3/9/201032373911,27696 $3,817$0.100CEA 1839-27839800 Mar-10 3/9/2010 4/8/201030405541,38496 $4,294$0.110CEA 1839-27839800 Apr-10 4/8/2010 5/10/201032393411,34390 $4,154$0.110CEA 1839-27839800 May-10 5/10/2010 6/9/201030358861,22588 $3,914$0.110CEA 1839-27839800 Jun-10 6/9/2010 7/9/2010301870463885 $2,051$0.110CEA 1839-27839800 Jul-10 7/9/2010 8/9/2010311496851146 $1,663$0.110CEA 1839-27839800 Aug-10 8/10/2010 9/10/2010312496885272 $2,682$0.110CEA 1839-27839800 Sep-10 9/11/2010 10/11/2010302563187577 $2,873$0.110CEA 1839-27839800 Oct-10 10/12/2010 11/10/2010292643390280 $2,932$0.110CEA 1839-27839800 Nov-10 11/11/2010 12/11/2010302659290885 $2,981$0.110CEA 1839-27839800 Dec-10 12/12/2010 1/10/201129304751,04085 $3,332$0.110Jan - 09 to Dec - 09 total:33507911,4361,096$45,3630Jan - 10 to Dec - 10 total:36352812,407996$39,0480$0.14$0.11Jan - 09 to Dec - 09 avg:Jan - 10 to Dec - 10 avg:Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
$3,000$4,000$5,000$6,0002500030000350004000045000Electric Cost ($)Electric Consumption (kWh)Benson High School - Electric Consumption (kWh) vs. Electric Cost ($)$0$1,000$2,000$3,00005000100001500020000Jan-09 Mar-09 May-09 Jul-09 Sep-09 Nov-09 Jan-10 Mar-10 May-10 Jul-10 Sep-10 Nov-10Electric Cost ($)Electric Consumption (kWh)Date (Mon - Yr)Electric Consumption (kWh)Electric Cost ($)Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Benson High School Final Energy Audit Report
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Appendix B
AkWarm Commercial Reports
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ENERGY AUDIT REPORT – PROJECT SUMMARY – Created 6/18/2012 11:37
AM
General Project Information
PROJECT INFORMATION AUDITOR INFORMATION
Building: Benson High School Auditor Company: Coffman Engineers, Inc.
Address: 4515 Campbell Airstrip Rd Auditor Name: Walter Heins
City: Anchorage Auditor Address: 800 F Street
Anchorage, AK 99501 Client Name: Calvin Mundt
Client Address: Auditor Phone: (907) 276,6664
Auditor FAX:
Client Phone: (907) 742,5213 Auditor Comment:
Client FAX:
Design Data
Building Area: 29,284 square feet Design Heating Load: Design Loss at Space: 1,144,292
Btu/hour
with Distribution Losses: 1,204,518 Btu/hour
Plant Input Rating assuming 82.0% Plant Efficiency and
25% Safety Margin: 1,836,156 Btu/hour
Note: Additional Capacity should be added for DHW
load, if served.
Typical Occupancy: 182 people Design Indoor Temperature: 68 deg F (building
average)
Actual City: Anchorage Design Outdoor Temperature: ,18 deg F
Weather/Fuel City: Anchorage Heating Degree Days: 10,816 deg F,days
Utility Information
Electric Utility: Chugach Electric , Commercial –
Sm
Natural Gas Provider: Enstar Natural Gas ,
Commercial , Sm
Average Annual Cost/kWh: $0.120/kWh Average Annual Cost/ccf: $0.970/ccf
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 Annual Energy Cost Estimate Description Space Heating Space Cooling Water Heating Lighting Other Electrical Cooking Clothes Drying Vent Fans Service Fees Total Cost Existing Building $30,437 $0 $2,616 $8,253 $1,688 $0 $0 $8,641 $0 $51,635 With Proposed Retrofits $27,447 $0 $3,729 $4,312 $844 $0 $0 $8,641 $0 $44,974 SAVINGS $2,990 $0 ,$1,113 $3,940 $844 $0 $0 $0 $0 $6,662
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 Annual Modeled Consumption (Blue) compared to Actual Electric (Left) and Natural Gas (Right) Consumption (Orange).
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 Monthly Modeled Consumption (Blue) compared to Actual Electric Consumption (Orange).
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 Monthly Modeled Consumption (Blue compared to Actual Natural Gas Consumption (Orange).
Benson High School Final Energy Audit Report
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Appendix C
Major Equipment List
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 MAJOR EQUIPMENT INVENTORY TAG LOCATION FUNCTION MAKE MODEL TYPE CAPACITY EFFICIENCY MOTOR SIZE ASHRAE SERVICE LIFE (YEARS) ESTIMATED REMAINING USEFUL LIFE (YEARS) B,1 BOILER RM BUILDING HEATING WEIL,MCLAIN 688 GAS FIRED CAST IRON 1703 MBH ≈ 83% 3/4 30 ≈ 10 B,2 BOILER RM BUILDING HEATING WEIL,MCLAIN 688 GAS FIRED CAST IRON 1703 MBH ≈ 83% 3/4 30 ≈ 10 P,1A BOILER RM HEATING WATER CIRC BELL & GOSSETT 1510 BASEMOUNT 280GPM ≈ 89.5 10 20 0 P,1B BOILER RM HEATING WATER CIRC BELL & GOSSETT 1510 BASEMOUNT 280GPM ≈ 89.5 10 20 0 P,2A BOILER RM HEATING WATER CIRC BELL & GOSSETT 80 INLINE 110GPM 40' ≈ 84% 3 10 0 P,2B BOILER RM HEATING WATER CIRC BELL & GOSSETT 80 INLINE 110GPM 40' ≈ 84% 3 10 0 P,3A BOILER RM HEATING WATER CIRC BELL & GOSSETT , INLINE 84GPM 10' ≈ 86.5% 2 10 0 P,3B BOILER RM HEATING WATER CIRC BELL & GOSSETT INLINE 84GPM 10' ≈ 86.5% 2 10 0 P,5 BOILER RM DOMESTIC HOT WATER RECIRC GRUNDFOS UP25,64 INLINE 4GPM ≈ 80% 1/4 10 0 AHU,1 FAN RM CLASSROOM SUPPLY McQUAY LSL150DV CABINET FAN 29000CFM 4.0" ≈ 86.5% 40 25 4 AHU,2 FAN RM MPR RM SUPPLY McQUAY LSL117DH CABINET FAN 8000CFM 1.5" ≈ 86.5% 5 25 4
Benson High School Final Energy Audit Report Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13 MAJOR EQUIPMENT INVENTORY TAG LOCATION FUNCTION MAKE MODEL TYPE CAPACITY EFFICIENCY MOTOR SIZE ASHRAE SERVICE LIFE (YEARS) ESTIMATED REMAINING USEFUL LIFE (YEARS) RF,1 FAN RM MPR RM RETURN GREENHECK SPNE,48,50 PROPELLER 25,750CFM .35" NEMA STANDARD 7.5 15 0 CF,1 BOILER RM COMBUSTION AIR , , PROPELLER 6609CFM 0.25” ≈ 80% 0.75 15 0 EF,1 FAN RM RESTROOM EXHAUST GREENHECK SFB10,15 PROPELLER 4050CFM .75" NEMA STANDARD 1.5 15 0 EF,2 FAN RM HOOD EXHAUST GREENHECK SFB10,10 PROPELLER 1500CFM 1.3" NEMA STANDARD 1 15 0
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Appendix D
Energy Conservation Measures
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The following tables consist of raw output data from the AkWarm Commercial program used to model
energy costs and calculate energy savings and financial ratios. These tables represent all of the energy
conservation measures calculated and considered by the energy audit team. However, ECMs included in
the Executive Summary and Section VIII are recommended by the energy audit team due to their viable
financial ratios (SIR>1) or due to their value added.
PRIORITY LIST – RECOMMENDED ENERGY CONSERVATION MEASURES
Rank Feature Recommendation Annual Energy
Savings
Installed
Cost
SIR Payback
(Years)
1 Setback Thermostat:
Multipurpose
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for the
Multipurpose space.
$824 $93 112.75 0.1
2 Setback Thermostat:
Intermittent/Storage/
Utility
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for the
Intermittent/Storage/Utility
space.
$1,983 $236 106.88 0.1
3 Lighting , Controls
Retrofit: Exterior
Pole Lighting Type
SA,SB
Add new Clock Timer or Other
Scheduling Control
$1,316 $250 81.03 0.2
4 Setback Thermostat:
Classroom/Office
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for the
Classroom/Office space.
$2,168 $463 59.57 0.2
5 Lighting , Controls
Retrofit: Exterior
Type HC,HE,HH
Remove On/Off Photoswitch
and Add new Clock Timer or
Other Scheduling Control
$363 $250 22.37 0.7
6 Lighting , Controls
Retrofit: Exterior
Bollard Lighting
Type SC
Add new Clock Timer or Other
Scheduling Control
$317 $250 19.51 0.8
7 Other Electrical ,
Controls Retrofit:
Vending Machines
Add new Other Controls $710 $750 6.05 1.1
8 Lighting , Controls
Retrofit: Exterior
Type HF
Add new Clock Timer or Other
Scheduling Control
$55 $250 3.40 4.5
9 Lighting , Power
Retrofit: Duct Chase
Lighting
Replace with FLUOR (14)
CFL, A Lamp 9W
$62 $140 2.83 2.3
10 Lighting , Power
Retrofit: Exterior
Type HC,HE,HH
Replace with 11 LED 20W
Module StdElectronic
$292 $2,200 2.04 7.5
11 Lighting , Controls
Retrofit: Gym
Lighting
Add new Multi,Level Switch $145 $1,500 1.45 10.3
12 Other Electrical ,
Controls Retrofit:
Snack vending
machines
Add new Other Controls $134 $750 1.14 5.6
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
13 Lighting , Power
Retrofit: Exterior
Bollard Lighting
Type SC
Replace with 13 LED 20W
Module StdElectronic
$233 $4,100 0.87 17.6
14 Lighting , Power
Retrofit: Corridor
CFL Type N
Downlight
Replace with 21 LED 12W
Module (2) StdElectronic
$177 $3,150 0.85 17.7
15 Lighting , Power
Retrofit: Exterior
Pole Lighting Type
SA,SB
Replace with 11 LED 150W
Module StdElectronic
$814 $16,500 0.76 20.3
16 Air Tightening Perform air sealing to reduce
air leakage by 20%.
$576 $8,600 0.60 14.9
17 Window/Skylight:
North Face ,
Windows
Install Lexan magnetic storm
window on interior
$100 $3,150 0.51 31.4
18 Ceiling w/ Attic:
Ventilated Roof
Install R,10 rigid foam board to
ceiling interior.
$1,197 $52,621 0.50 44
19 Window/Skylight:
West Face ,
Windows
Install Lexan magnetic storm
window on interior
$70 $2,284 0.49 32.6
20 Window/Skylight:
East Face , Windows
Install Lexan magnetic storm
window on interior
$70 $2,205 0.51 31.6
21 Window/Skylight:
South Face ,
Windows
Install Lexan magnetic storm
window on interior
$171 $6,221 0.44 36.3
22 Exterior Door: West
Face , Doors
w/windows
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$12 $820 0.31 70.7
23 Exterior Door: South
Face , Doors
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$23 $1,640 0.31 70.7
24 Exterior Door: East
Face , Doors
w/windows
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$8 $820 0.21 107.4
25 Exterior Door: North
Face , Doors
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$3 $820 0.07 314.7
26 Exterior Door: East
Face , Doors w/o
windows
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$3 $820 0.07 315.6
27 Exterior Door: West
Face , Doors w/o
windows
Remove existing door and
install standard pre,hung U,
0.16 insulated door, including
hardware.
$3 $820 0.07 313.3
28 HVAC And DHW Upgrade existing boilers with
modulating boilers
,$5,167 $103,911 ,0.74 ,20.1
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
TOTAL $6,662 $215,613 0.41 32.4
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
ENERGY AUDIT REPORT – ENERGY EFFICIENT RECOMMENDATIONS
1. Building Envelope
Insulation
Rank Location Existing Type/R9Value Recommendation Type/R9
Value
Installed
Cost
Annual
Energy
Savings
18 Ceiling w/ Attic:
Ventilated Roof
Framing Type: Energy Truss
Framing Spacing: 24 inches
Insulated Sheathing: None
Bottom Insulation Layer: R,19
Batt:FG or RW, 6 inches
Top Insulation Layer: None
Modeled R,Value: 21.3
Install R,10 rigid foam
board to ceiling interior.
$52,621 $1,197
Exterior Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
22 Exterior Door:
West Face , Doors
w/windows
Door Type: Metal/PU half lite
Modeled R,Value: 3.3
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$820 $12
23 Exterior Door:
South Face , Doors
Door Type: Metal/PU half lite
Modeled R,Value: 3.3
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$1,640 $23
24 Exterior Door: East
Face , Doors
w/windows
Door Type: Metal/PU quarter
lite
Modeled R,Value: 4
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$820 $8
25 Exterior Door:
North Face , Doors
Door Type: Metal , urethane,
therm. break
Modeled R,Value: 5.3
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$820 $3
26 Exterior Door: East
Face , Doors w/o
windows
Door Type: Metal , urethane,
therm. break
Modeled R,Value: 5.3
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$820 $3
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Exterior Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
27 Exterior Door:
West Face , Doors
w/o windows
Door Type: Metal , urethane,
therm. break
Modeled R,Value: 5.3
Remove existing door and
install standard pre,hung U,
0.16 insulated door,
including hardware.
$820 $3
Windows and Glass Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
17 Window/Skylight:
North Face ,
Windows
Glass: Triple, 1 Low,E Coating
Frame: Aluminum, No Thermal
Break
Spacing Between Layers: Half
Inch
Gas Fill Type: Air
Modeled U,Value: 0.61
Solar Heat Gain Coefficient
including Window Coverings:
0.39
Install Lexan magnetic
storm window on interior
$3,150 $100
19 Window/Skylight:
West Face ,
Windows
Glass: Triple, 1 Low,E Coating
Frame: Aluminum, No Thermal
Break
Spacing Between Layers: Half
Inch
Gas Fill Type: Air
Modeled U,Value: 0.61
Solar Heat Gain Coefficient
including Window Coverings:
0.39
Install Lexan magnetic
storm window on interior
$2,284 $70
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Windows and Glass Doors – Replacement
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
20 Window/Skylight:
East Face ,
Windows
Glass: Triple, 1 Low,E Coating
Frame: Aluminum, No Thermal
Break
Spacing Between Layers: Half
Inch
Gas Fill Type: Air
Modeled U,Value: 0.61
Solar Heat Gain Coefficient
including Window Coverings:
0.39
Install Lexan magnetic
storm window on interior
$2,205 $70
21 Window/Skylight:
South Face ,
Windows
Glass: Triple, 1 Low,E Coating
Frame: Aluminum, No Thermal
Break
Spacing Between Layers: Half
Inch
Gas Fill Type: Air
Modeled U,Value: 0.61
Solar Heat Gain Coefficient
including Window Coverings:
0.39
Install Lexan magnetic
storm window on interior
$6,221 $171
Air Leakage
Rank Location Estimated Air Leakage Recommended Air Leakage
Target
Installed
Cost
Annual
Energy
Savings
16 Air Tightness estimated as: 0.73
cfm/ft2 of above,grade shell
area at 75 Pascals
Perform air sealing to
reduce air leakage by 20%.
$8,600 $576
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
2. Mechanical Equipment
Mechanical
Rank Recommendation Installed
Cost
Annual
Energy
Savings
28 Upgrade existing boilers with modulating boilers $103,911 ,$5,167
Setback Thermostat
Rank Location Size/Type/Condition Recommendation Installed
Cost
Annual
Energy
Savings
1 Multipurpose Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Multipurpose space.
$93 $824
2 Intermittent/Storag
e/Utility
Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the
Intermittent/Storage/Utility
space.
$236 $1,983
4 Classroom/Office Existing Unoccupied Heating
Setpoint: 70.0 deg F
Implement a Heating
Temperature Unoccupied
Setback to 60.0 deg F for
the Classroom/Office
space.
$463 $2,168
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
3. Appliances and Lighting
Lighting Fixtures and Controls
Rank Location Existing Recommended Installed
Cost
Annual
Energy
Savings
3 Exterior Pole
Lighting Type
SA,SB
11 HPS 400 Watt Magnetic
with On/Off Photoswitch
Add new Clock Timer or
Other Scheduling Control
$250 $1,316
5 Exterior Type
HC,HE,HH
11 HPS 100 Watt Magnetic
with On/Off Photoswitch
Remove On/Off
Photoswitch and Add new
Clock Timer or Other
Scheduling Control
$250 $363
6 Exterior Bollard
Lighting Type SC
13 HPS 70 Watt Magnetic with
On/Off Photoswitch
Add new Clock Timer or
Other Scheduling Control
$250 $317
8 Exterior Type HF 7 LED Wall Pack with On/Off
Photoswitch
Add new Clock Timer or
Other Scheduling Control
$250 $55
9 Duct Chase
Lighting
INCAN (14) A Lamp, Std 60W
with Manual Switching
Replace with FLUOR (14)
CFL, A Lamp 9W
$140 $62
10 Exterior Type
HC,HE,HH
11 HPS 100 Watt Magnetic
with On/Off Photoswitch
Replace with 11 LED 20W
Module StdElectronic
$2,200 $292
11 Gym Lighting 24 FLUOR (4) T5 45.2"
F54W/T5 HO Standard (2)
HighEfficElectronic with
Manual Switching
Add new Multi,Level
Switch
$1,500 $145
13 Exterior Bollard
Lighting Type SC
13 HPS 70 Watt Magnetic with
On/Off Photoswitch
Replace with 13 LED 20W
Module StdElectronic
$4,100 $233
14 Corridor CFL Type
N Downlight
21 FLUOR (2) CFL, Plug,in
26W Quad Tube (2)
StdElectronic with Clock Timer
or Other Scheduling Control
Replace with 21 LED 12W
Module (2) StdElectronic
$3,150 $177
15 Exterior Pole
Lighting Type
SA,SB
11 HPS 400 Watt Magnetic
with On/Off Photoswitch
Replace with 11 LED
150W Module
StdElectronic
$16,500 $814
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Appendix E
Site Survey Photos
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
1. School Exterior – South Face 2. Main Entrance
3. Typical Window 4. Heating Water Pumps, P,1A and P,1B
5. Gas,Fired Boiler , B,1 6. Indirect Water Heater
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
7. Kitchen Sectional Door 8. Kitchen Freezer
9. Duct Chase 10. LED Lighting
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Appendix F
Thermographic Photos
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
Coffman Engineers made miscellaneous thermographic images of Benson High School using a FLIR
T300 Infrared Camera. This is not a thermographic study, rather photographs to illustrate easy,to,identify
heat losses.
1. Optical Image, South Face. Thermal Image below is indicated by the white border.
2. Thermographic Image, South Face. Temperatures indicated by color scale on right. Yellow
indicates heat leakage. The outside temperature was about ,15°F.
Benson High School Final Energy Audit Report
Coffman Engineers, Inc. 6/18/2012 AkWarm No. CIRI,ANC,CAEC,13
3. Optical Image, South Face. Thermal Image
below is indicated by the white border.
4. Optical Image, School Entrance. Thermal
Image below.
5. Thermographic image, Roof Vents. Heat
loss from a ventilated roof is expected..
6. Thermal Image, School Entrance. No
unusual heat loss observed.
7. Thermal Image, Foundation. Heat losses
from the insulated slab edges are
reasonable. The outside temperature was
about ,7°F.
End of Report