HomeMy WebLinkAboutSEA-AEE-JNU Thunder Mountain High School 2012-EE
Thunder Mountain High School
Juneau School District
Funded by:
Final Report
January 2012
Prepared by:
Energy Audit
Table of Contents
Section 1: Executive Summary 2
Section 2: Introduction 5
Section 3: Energy Efficiency Measures 8
Section 4: Description of Systems 14
Section 5: Methodology 18
Appendix A: Energy and Life Cycle Cost Analysis 21
Appendix B: Energy and Utility Data 29
Appendix C: Equipment Data 36
Appendix D: Abbreviations 45
Audit Team
The energy audit is performed by Alaska Energy Engineering LLC of Juneau, Alaska. The audit team
consists of:
Jim Rehfeldt, P.E., Energy Engineer
Jack Christiansen, Energy Consultant
Brad Campbell, Energy Auditor
Loras O’Toole P.E., Mechanical Engineer
Will Van Dyken P.E., Electrical Engineer
Curt Smit, P.E., Mechanical Engineer
Philip Iverson, Construction Estimator
Karla Hart, Technical Publications Specialist
Jill Carlile, Data Analyst
Grayson Carlile, Energy Modeler
Thunder Mountain High School 1 Energy Audit (January 2012)
Section 1
Executive Summary
An energy audit of the Thunder Mountain High School was performed by Alaska Energy Engineering
LLC. The investment grade audit was funded by Alaska Housing Finance Corporation (AHFC) to
identify opportunities to improve the energy performance of public buildings throughout Alaska.
Thunder Mountain High School is a 168,842 square foot building that contains offices, classrooms,
commons, a main and an auxiliary gym, an auditorium, and mechanical support spaces.
Building Assessment
The following summarizes our assessment of the building:
Envelope
The design and construction of the building envelope has resulted in a very leaky building. Air
infiltration is most heavily focused around the roof pan decking and building support beams. Air
infiltration through the building envelope is so significant that rooms E101, E205, E206, and E208
cannot be adequately heated to a comfortable level without the use of portable space heaters.
The building heating and ventilation systems are only efficient and effective if the building envelope
is tightly sealed. The failure to seal the building envelope, combined with ventilation systems that
modulate based on building pressure, has resulted in a negatively pressurized building. This is
causing a large amount of air infiltration through the building envelope, a condition that creates
uncomfortable drafts, increases the heating loads, and may reduce the life of the building.
Other non-optimal features of the envelope are exterior doors that are not thermally broken and a
broken window on the southwest face.
Heating System
The building is heated by three fuel oil boilers that provide heat to ten air handling unit systems, fan
coil units, and perimeter hydronic heating units. With exception to the boiler #3 leak that is currently
under repair, the fuel oil boiler heating system is in good condition. However, fairly simple
improvements can be made to improve its effectiveness and efficiency. These are outlined in Section
3, Energy Efficiency Measures.
Cooling Systems
A ground water cooling system is installed to supply cooling coils in four of the ten large air handling
units. This system is not used and has been abandoned.
A roof top unit provides cooling for the building server room. This system does not recover the heat
for use within the building envelope.
Thunder Mountain High School 2 Energy Audit (January 2012)
Ventilation System
The building ventilation systems consists of seven large air handling units (located in three interior
fan rooms) and three roof top units that supply conditioned air. In addition to the large air handling
units, there are sixty-one exhaust fans that provide cooling, remove poor quality air, support kitchen
operations, and fume hood exhaust air flow in the science labs. This large number of exhaust fans
makes it difficult to combine exhaust flows to create a high air flow rate that can economically be
connected to a heat recovery system.
The ventilation systems were designed to ventilate the building beyond the code requirements based
on occupancy. The Juneau School District has reduced the ventilation by changing the mixed air
temperature setpoint on the systems. These changes have significantly reduced energy costs.
Lighting
Interior lighting consists primarily of T8, T5, and compact fluorescent fixtures, and metal halide
lighting. Exterior lighting consists primarily of metal halide lighting. The interior lighting is
controlled by staff and the exterior lighting by a photocell. Lighting operational hours and subsequent
electrical demand are kept to a minimum.
Summary
It is the assessment of the energy audit team that the Thunder Mountain High School staff is very
focused on lowering energy consumption at the facility in their daily operations. The majority of the
energy efficiency opportunities are due to a substandard building envelope combined with non-
optimal control sequences.
Outlined within this report are recommendations for a building envelope leakage test, modifications
to the building control sequences, and subsequent building retro-commissioning.
Energy Efficiency Measures (EEMs)
All buildings have opportunities to improve their energy efficiency. The energy audit revealed
numerous opportunities in which an efficiency investment will result in a net reduction in long-term
operating costs.
Behavioral and Operational EEMs
The following EEM requires behavioral and operational changes in the building use. The savings are
not readily quantifiable but this EEM is highly recommended as a low-cost opportunity that is a
standard of high performance buildings.
EEM-1: Weather-strip Doors
Thunder Mountain High School 3 Energy Audit (January 2012)
High and Medium Priority EEMs
The following EEMs are recommended for investment. They are ranked by life cycle savings to
investment ratio (SIR). This ranking method places a priority on low cost EEMs which can be
immediately funded, generating energy savings to fund higher cost EEMs in the following years.
25-Year Life Cycle Cost Analysis
Investment Operating Energy Total SIR
High Priority
EEM-2: Lower Entrance Temperature $100 $0 ($33,300) ($33,200) 333
EEM-3: Replace Aerators and Showerheads $2,900 $0 ($80,700) ($77,800) 27.8
EEM-4: Install Kiln Room Cooling $3,800 $0 ($32,900) ($29,100) 8.7
EEM-5: Reduce Infiltration /Optimize HVACs $205,100 $17,000 ($1,599,200) ($1,377,100) 7.7
EEM-6: Install Heat Recovery - Server Room E102 $28,400 $0 ($208,500) ($180,100) 7.3
EEM-7: Install Heat Recovery - Electric Room F207 $9,200 $1,700 ($59,500) ($48,600) 6.3
EEM-8: Install Heat Recovery - Boiler Room $81,700 $4,300 ($384,900) ($298,900) 4.7
EEM-9: Reduce Gym Lighting $8,900 ($9,500) ($25,100) ($25,700) 3.9
EEM-10: Modify Unoccupied Heating Coil Controls $10,800 $0 ($34,200) ($23,400) 3.2
EEM-11: Convert Kitchen Hood to Variable Flow $27,500 $0 ($83,200) ($55,700) 3.0
Medium Priority
EEM-12: Install Valves on Unit Heaters $3,600 $0 ($6,500) ($2,900) 1.8
EEM-13: Install Heat Recovery - Electric Room K106 $16,700 $3,400 ($27,700) ($7,600) 1.5
EEM-14: Upgrade Transformers $118,100 $0 ($144,800) ($26,700) 1.2
Totals* $516,800 $16,900 ($2,720,500) ($2,186,800) 5.2
*The analysis is based on each EEM being independent of the others. While it is likely that some
EEMs are interrelated, an isolated analysis is used to demonstrate the economics because the audit
team is not able to predict which EEMs an Owner may choose to implement. If several EEMs are
implemented, the resulting energy savings is likely to differ from the sum of each EEM projection.
Summary
The energy audit revealed numerous opportunities for improving the energy performance of the
building. It is recommended that the behavioral and high priority EEMs be implemented now to
generate energy savings from which to fund the medium priority EEMs.
Another avenue to consider is to borrow money from AHFCs revolving loan fund for public
buildings. AHFC will loan money for energy improvements under terms that allow for paying back
the money from the energy savings. More information on this option can be found online at
http://www.ahfc.us/loans/akeerlf_loan.cfm.
Thunder Mountain High School 4 Energy Audit (January 2012)
Section 2
Introduction
This report presents the findings of an energy audit of Thunder Mountain High School located in
Juneau, Alaska. The purpose of this investment grade energy audit is to evaluate the infrastructure
and its subsequent energy performance to identify applicable energy efficiencies measures (EEMs).
The energy audit report contains the following sections:
Introduction: Building use and energy consumption.
Energy Efficiency Measures: Priority ranking of the EEMs with a description, energy analysis,
and life cycle cost analysis.
Description of Systems: Background description of the building energy systems.
Methodology: Basis for how construction and maintenance cost estimates are derived and the
economic and energy factors used for the analysis.
BUILDING USE
Thunder Mountain High School is a 168,842 square foot building that contains offices, classrooms,
commons, a main and an auxiliary gym, an auditorium, and mechanical support spaces. The building
was designed for 1,200 occupants and currently has approximately 700 (682 students and 98 staff). It
is occupied in the following manner:
Offices: 8:00 am - 5:00 pm (M-F)
Commons: 8:00 am – 8:00 pm (M-Su)
Classrooms: 8:30 am - 4:30 pm (M-F)
Gym/Aux Gym 8:00 am – 10:00 pm for use by students and the Community Schools (M-Su)
Weight room 6:30 am – 4:30 pm (M-F)
Auditorium 8:30 am – 8:30 pm (6 days/week average)
Lunchroom 8:30 am – 9:10 am & 12:00 pm – 12:40 pm
Janitorial Hours 6:00 pm – 2:00 am (Su-Th)
Building History
2007 – Original Construction
Thunder Mountain High School 5 Energy Audit (January 2012)
Energy and Water Consumption
The building energy sources include an electric service and a fuel oil tank. Fuel oil supplies space and
domestic hot water heating and electricity serves all other loads. The following table shows annual
energy use and cost.
Annual Energy Consumption and Cost
Source Consumption Cost Energy, MMBtu
Electricity 1,203,240 kWh $124,200 4,100 33%
Fuel Oil 60,614 Gallons $230,300 8,200 67%
Totals $354,500 12,300 100%
Electricity
This chart shows electrical energy use
since the building was first occupied in
2009. The effective cost—energy costs
plus demand charges—is 10.3¢ per kWh.
Fuel Oil
This chart shows heating energy use from 2009 to 2010. The
chart compares annual use with the heating degree days which
is a measurement of the demand for energy to heat a building.
A year with a higher number of degree days reflects colder
outside temperatures and a higher heating requirement.
Thunder Mountain High School 6 Energy Audit (January 2012)
Cost of Heat Comparison
This chart shows a comparison of the current cost of
fuel oil heat and electric heat. The comparison is
based on a fuel oil conversion efficiency of 70% and
an electric boiler conversion efficiency of 95%.
Electric heat is currently less expensive than fuel
oil heat.
Water
Water consumption averages 625,000 gallons per year. Water
and wastewater costs $10.96 per 1000 gallons.
Thunder Mountain High School 7 Energy Audit (January 2012)
Section 3
Energy Efficiency Measures
The following energy efficiency measures (EEMs) were identified during the energy audit. The
EEMs are priority ranked and, where applicable, subjected to energy and life cycle cost analysis.
Appendix A contains the energy and life cycle cost analysis spreadsheets.
The EEMs are grouped into the following prioritized categories:
Behavioral or Operational: EEMs that require minimal capital investment but require
operational or behavioral changes. The EEMs provide a life cycle savings but an analysis is not
performed because the guaranteed energy savings is difficult quantify.
High Priority: EEMs that require a small capital investment and offer a life cycle savings. Also
included in this category are higher cost EEMs that offer significant life cycle savings.
Medium Priority: EEMs that require a significant capital investment to provide a life cycle
savings. Many medium priority EEMs provide a high life cycle savings and offer substantial
incentive to increase investment in building energy efficiency.
BEHAVIORAL OR OPERATIONAL
The following EEM is recommended for implementation. It requires behavioral or operational
changes that can occur with minimal investment to achieve immediate savings. This EEM is not
easily quantified by analysis because it cannot be accurately predicted. It is recommended because it
offers a life cycle savings, represents good practice, and is and accepted feature of high performance
buildings.
EEM-1: Weather-strip Doors
Purpose: All exterior double doors are ineffectively weather-stripped where the doors contact the
center astragal. The doors and astragals have metal-to-metal contact, evidenced by the
obvious banging sound when the doors close.
Overhead door #12 in the Cargo Bay also has a damaged section of weather stripping.
Energy will be saved if doors are properly weather-stripped to reduce infiltration.
Scope: Add an effective weather- stripping to the center bar on all double doors and repair the
weather stripping on Cargo Bay overhead door #12.
Thunder Mountain High School 8 Energy Audit (January 2012)
HIGH PRIORITY
The following EEMs are recommended for implementation because they are low cost measures that
have a high savings to investment ratio. The EEMs are listed from highest to lowest priority. Negative
values, in parenthesis, represent savings.
EEM-2: Lower Entrance Temperature
Purpose: The auditorium entryway (southeast corner of building) cabinet unit heater is maintaining
a temperature of 80°F in the arctic entrance. Energy will be saved if the set point for this
space is lowered to 55°F.
Scope: Lower the cabinet unit heater setpoint from 80°F to 55°F.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($1,180) ($1,180) $100 $0 ($33,300) ($33,200) 333.0
EEM-3: Replace Aerators and Showerheads
Purpose: Energy and water will be saved by replacing the lavatory aerators and showerheads with
low-flow models.
Scope: Replace lavatory aerators and showerheads with water-conserving fixtures.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($3,160) ($3,160) $2,900 $0 ($80,700) ($77,800) 27.8
EEM-4: Install Kiln Room Cooling
Purpose: RTU-4 supplies cooling to the Kiln Room when the kiln is operating. This requires
RTU-4 to operate an additional 430 hours per year during unoccupied hours when the
unit is usually off, just to cool the kiln room. Energy will be saved if outside air is used
to cool the kiln room without operating RTU-4.
Scope: Connect an automatic damper to the unused exhaust louver in the outside wall and extend
a duct to the floor. Interlock the damper to open whenever EF-E4 is operating to cool the
kiln room.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($1,320) ($1,320) $3,800 $0 ($32,900) ($29,100) 8.7
Thunder Mountain High School 9 Energy Audit (January 2012)
EEM-5: Reduce Infiltration / Optimize HVAC Systems
Purpose: The design and construction of the building envelope resulted in significant leakage
paths. Air infiltration is prevalent, a condition that is exasperated by high exhaust air
flows and ventilation system controls that keep the building at negative pressure to the
outside. Energy will be saved, and the life of the structure extended, if the accessible
leakage paths are sealed and the control sequences modified to maintain the building at
neutral pressure.
Scope: Perform a leakage test of the exterior envelope and seal accessible leakage paths
including the wall/roof interface where the roof pan decking is poorly sealed.
Modify the following ventilation systems control sequences to provide optimal control of
return/relief fans and relief air dampers:
- RTU-1 (Classrooms), RTU-2 (Classrooms), RTU-4 (Classrooms), AHU-6 (Music),
and AHU-9 (Media): Install IAQ damper to maintain minimum outside air flow.
Change to sequential control of mixing dampers and automatic valve to maintain
62°F supply air temperature. Modulate return fan to maintain positive pressure
upstream of return air damper. Modulate relief damper to maintain neutral building
pressure.
- AHU-3 (Commons), AHU-6 (Gym), and AHU-7 (Aux. Gym): Change to sequential
control of mixing dampers and automatic valve to maintain room setpoint with CO2
sensor over-ride of mixing dampers. Modulate relief fans to maintain neutral building
pressure.
- Retro-commission the ventilation system controls to ensure optimal operation.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$1,000 ($56,810) ($55,810) $205,100 $17,000 ($1,599,200) ($1,377,100) 7.7
EEM-6: Install Heat Recovery - Server Room E102
Purpose: The server room is currently cooled by a 5-ton split cooling unit with the condensing unit
on the roof. Energy will be saved by installing an indoor ducted condensing unit that
transfers the heat to the commons.
Scope: Install a ducted condensing unit in the server room. Install supply and return ducts that
circulate commons are through the condenser to reject the heat to the commons.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($7,350) ($7,350) $28,400 $0 ($208,500) ($180,100) 7.3
Thunder Mountain High School 10 Energy Audit (January 2012)
EEM-7: Install Heat Recovery - Electrical Room F207
Purpose: The electrical room F207 utilizes a 500 kVA transformer and heat generated from this
unit is being exhausted outside the building by EF-F1. Energy will be saved if the heat
generated from the transformer is utilized within the building envelope.
Scope: Install a utility fan and transfer duct to supply heated air to the media center and a grille
and duct to transfer air back to the electrical room.
Operating Energy Total Investment Operating Energy Total SIR
$100 ($2,100) ($2,000) $9,200 $1,700 ($59,500) ($48,600) 6.3
EEM-8: Install Heat Recovery - Boiler Room
Purpose: The boiler room utilizes CF-1 to cool the room with outside air. Boilers and heating
equipment have significant heat loss that can be utilized within the building. Energy will
be saved if the heat generated from the boiler room is transferred to the main gymnasium.
Scope: Install a heat pump in the boiler room to transfer the heat to a fan coil unit in the gym.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$250 ($12,740) ($12,490) $81,700 $4,300 ($384,900) ($298,900) 4.7
EEM-9: Reduce Gym Lighting
Purpose: Light levels in the gym and auxiliary gym provide 75 foot-candles of illumination,
sufficient for high school basketball games. Energy will be saved if light levels in the
gyms are reduced during school hours while maintaining proper levels for the activity.
Scope: Program the lighting control panel to turn off some of the gym and auxiliary light fixtures
during school and activity hours when full lighting is not needed.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
($560) ($1,820) ($2,380) $8,900 ($9,500) ($25,100) ($25,700) 3.9
EEM-10: Modify Unoccupied Heating Coil Controls
Purpose: The AHU and RTU heating coils are maintaining the supply air temperature even when
the fan is off. This causes the automatic valve to be open and the fan cabinet to be hot
whenever the fan is off. The purpose of this control is to ensure the coil does not freeze
during cold weather. As a result heat builds up in the units and is lost to the surrounding
spaces and/or ducting. Energy will be saved if the sequence is changed to open the
automatic valve 15% whenever the outside temperature is below 32°F.
Scope: Modify the control sequence to close the heating coil automatic valve when the fan is in
unoccupied mode. When outside temperatures are below 32°F, position the valve to 15%
open to preclude freezing the coil.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($1,210) ($1,210) $10,800 $0 ($34,200) ($23,400) 3.2
Thunder Mountain High School 11 Energy Audit (January 2012)
EEM-11: Convert Kitchen Hood to Variable Flow
Purpose: The kitchen hood is manually controlled and operates for 3 hours per day at 8,300 cfm.
The minimum flow for the hood is 824 cfm. Energy will be saved by converting the hood
to variable speed so it can operate at lower exhaust rates when cooking activities do not
warrant full speed exhaust.
Data: Install a VFD and modify the hood control panel to modulate the fan with cooking
activity under the hood.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($2,950) ($2,950) $27,500 $0 ($83,200) ($55,700) 3.0
Thunder Mountain High School 12 Energy Audit (January 2012)
MEDIUM PRIORITY
Medium priority EEMs will require planning and a higher level of investment. They are
recommended because they offer a life cycle savings. The EEMs are listed from highest to lowest
priority. Negative values, in parenthesis, represent savings.
EEM-12: Install Automatic Valves on Unit Heaters (4 ceiling mounted unit heaters)
Purpose: Energy will be saved if each of the 4 unit heaters located in the boiler and fan rooms has
an automatic valve that shuts off the heating flow when heat is not needed. Currently, the
coils in the unit heaters are continuously hot and the thermostat turns on the fan to supply
the heat to the room. When heat is not needed, convective heat loss from the coil occurs;
some of the heat loss may be useful, but a large percentage is not.
Scope: Install automatic valves in the heating supply to each unit heater and control them from
the fan thermostat.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($230) ($230) $3,600 $0 ($6,500) ($2,900) 1.8
EEM-13: Electrical Room K106 Heat Recovery
Purpose: The electrical room K106 has a 150 kVA transformer. The heat generated from this unit
is exhausted outside the building by EF-K4. Energy will be saved if the heat generated
from the transformer is transferred to the gym by utilizing the gym fan coil unit that is
part of the proposed boiler room heat recovery system.
Scope: Install a heat pump in Electric Room K106 and transfer the heat to the gym fan coil unit
that is part of the boiler room heat recovery system.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$200 ($790) ($590) $16,700 $3,400 ($27,700) ($7,600) 1.5
Upgrade Transformers
Purpose: One 15 kVA, three 30 kVA, one 75 kVA, three 150 kVA, and one 300 kVA transformer
in the building are not TP-1 rated. Energy will be saved if these less-efficient
transformers are replaced with energy efficient models that comply with NEMA Standard
TP 1-2001.
Scope: Replace less-efficient transformers with a NEMA Standard TP 1-2001 compliant model.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($7,360) ($7,360) $118,100 $0 ($144,800) ($26,700) 1.2
Thunder Mountain High School 13 Energy Audit (January 2012)
Section 4
Description of Systems
ENERGY SYSTEMS
This section provides a general description of the building systems. Energy conservation
opportunities are addressed in Section 3, Energy Efficiency Measures.
Building Envelope
R-value
Component Description (inside to outside) Existing Optimal
Exterior Wall 5/8” Gyp. Bd, 1 ½” Rmax, 6” steel studs w/ R-19 batt, steel panel R-19 R-26
Roof 1/2” Gyp. Bd, 8” EPS rigid insulation, 7/16” OSB, pvc membrane R-34 R-46
Floor Slab Concrete slab-on-grade w/1’ polystyrene under slab R-15 R-10
Foundation 8” concrete with 3” x 2’ XPS insulation on exterior surface R-15 R-20
Windows Aluminum; double pane R-1.5 R-5
Doors Aluminum w/o thermal break, glazing where used is double pane R-1.5 R-5
Heating System
The building is heated by three fuel oil boilers and a hydronic heating system serving ten air handling
unit systems and perimeter heating units. The heating system has the following pumps:
PMP-1, PMP-2, and PMP-3 are the boiler circulation pumps for boilers 1, 2, and 3 respectively.
PMP-4A, PMP-4B, and PMP-4C are the building heating pumps.
Domestic Hot Water System
An oil fired hot water heater and an indirect hot water heater supplies domestic hot water to the
fixtures. The water conservation efficiency of the lavatory aerators and the showerheads can be
improved.
Cooling Systems
Air handling units AHU-3, AHU-5, AHU-6, and RTU-4 have integral cooling coils for the cooling of
interior spaces. Pumps PMP-5A and PMP-5B are the chilled water cooling pumps. This system has
been abandoned.
Roof top unit AC-1 provides cooling for the building server room.
Automatic Control System
The building has a DDC system to control the operation of the heating and ventilation systems.
Thunder Mountain High School 14 Energy Audit (January 2012)
Ventilation Systems
Area Fan
System Description
Academic Wing RTU-1 Variable volume air handling unit consisting of a heating coil, mixing
box, filter section, supply fan, and return air fan
Academic Wing RTU-2 Variable volume air handling unit consisting of a heating coil, mixing
box, filter section, supply fan, and return air fan
Commons AHU-3 Variable volume air handling unit consisting of a heating coil, cooling
coil, mixing box, filter section, supply fan, and 2 return air fans
Core Areas RTU-4 Variable volume air handling unit consisting of a heating coil, cooling
coil, mixing box, filter section, supply fan, and a return fan
Auditorium AHU-5 Variable volume air handling unit consisting of a heating coil, cooling
coil, mixing box, filter section, supply fan, and a return fan
Music, Support Areas AHU-6 Constant volume air handling unit consisting of a heating coil, cooling
coil, mixing box, filter section, supply fan, and 2 return air fans
Main Gym AHU-7 Constant volume air handling unit consisting of a heating coil, mixing
box, filter section, supply fan, and 2 return air fans
Auxiliary Gym AHU-8 Variable volume air handling unit consisting of heating coils, mixing
box, filter section, and a supply fan
Media AHU-9 Variable volume air handling unit consisting of a heating coil, cooling
coil, mixing box, filter section, and a supply fan
Boiler Room K107 AHU-10 Constant volume air handling unit consisting of a mixing box, filter
section, and a supply fan
Electric Room C108 CF-C1 2000 cfm ¼ hp belt drive cabinet fan, horizontal discharge
Electric Room C208 CF-C2 200 cfm 121 W direct drive cabinet fan, horizontal discharge
Electric Room D120 CF-D1 2000 cfm ¼ hp belt drive cabinet fan, horizontal discharge
Electric Room D218 CF-D2 200 cfm 121 W direct drive cabinet fan, horizontal discharge
Electric Room F207 CF-F1 1,200 cfm ¼ hp belt drive roof mounted fan
Area F Toilet Exhaust EF-F1 625 cfm ¼ hp belt drive roof exhauster
Media Toilet Exhaust EF-F2 75 cfm 80 W ceiling exhaust fan
F111 Ventilated Booth EF-F3 800 cfm ¾ hp upblast roof exhauster
Art Wedging Table Exhaust EF-F4 1,200 cfm ¾ hp upblast roof exhauster
Art Room General Exhaust EF-F5 2,700 cfm 1 hp upblast roof exhauster
Art Ventilated Booth EF-F6 800 cfm ¾ hp upblast roof exhauster
Testing Room F116 EF-F7 120 cfm 78 W clothes dryer exhaust booster
Testing Room F116 EF-F8 350 cfm 242 W direct drive range hood exhaust inline centrifugal fan
Area G Toilet Exhaust EF-G1 1,275 cfm ½ hp belt drive roof exhauster
Custodial Exhaust G103 EF-G2 75 cfm 80 W ceiling exhaust fan
Applied Tech Vent Booth EF-G3 800 cfm ¾ hp upblast roof exhauster
Scene Shop Vent Booth EF-G4 800 cfm ¾ hp upblast roof exhauster
Women’s Toilet Exhaust EF-J1 450 cfm 1/6 hp belt drive roof exhauster
Laundry J102 EF-J2 120 cfm 78 W in-line clothes dryer exhaust booster
Thunder Mountain High School 15 Energy Audit (January 2012)
Ventilation Systems, continued.
Area Fan
System Description
Locker Rooms EF-K1 3,120 cfm ½ hp belt drive roof exhauster
Small Engine Welding EF-K2 1,200 cfm 1 ½ hp belt drive centrifugal fan
Custodial H110 EF-K3 210 cfm 80 W ceiling fan
Main Electric Room K106 EF-K4 1,800 cfm ½ hp roof exhauster
Small Engine EF-K5 800 cfm ¼ hp belt drive roof exhauster
Small Engine Ventilated
Booth
EF-K6 1,050 cfm ¾ hp explosion proof upblast roof exhauster
Faculty Toilet Exhaust EF-L1 75 cfm 80 W ceiling exhaust fan
Toilet Exhaust EF-L2 75 cfm 80 W ceiling exhaust fan
Area B Toilet Exhaust EF-B1 300 cfm 1/6 hp belt drive roof exhauster
Area C Toilet Exhaust EF-C1 1,670 cfm 1/3 hp belt drive roof exhauster
Area C Janitor Exhaust EF-C2 420 cfm 1/6 hp belt drive roof exhauster
Area C Science Rm. Exhaust EF-C3 2,400 cfm ¾ hp belt drive roof exhauster
Fume Hood Exhaust C219 EF-C4 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust C119 EF-C5 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust C220 EF-C6 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust C120 EF-C7 825 cfm ½ hp roof top fume hood exhaust fan
Area D Toilet Exhaust EF-D1 1,670 cfm 1/3 hp belt drive roof exhauster
Area D Janitor Exhaust EF-D2 300 cfm 1/6 hp belt drive roof exhauster
Area D Science Rm.Exhaust EF-D3 4000 cfm 2 hp belt drive roof exhauster
Fume Hood Exhaust D202 EF-D4 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust D103 EF-D5 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust D205 EF-D6 825 cfm ½ hp roof top fume hood exhaust fan
Fume Hood Exhaust D105 EF-D7 825 cfm ½ hp roof top fume hood exhaust fan
Kitchen Hood H-1 E111 EF-E1 8,300 cfm 7 ½ hp belt drive roof exhauster
Kitchen Hood H-2 E-111 EF-E2 600 cfm 1/3 hp belt drive roof exhauster
Janitor Exhaust E115 EF-E3 75 cfm 80 W ceiling fan
Kiln Exhaust E119 EF-E4 80 cfm 135 W kiln ventilation system
Kiln Exhaust E119 EF-E5 80 cfm 135 W kiln ventilation system
Janitor Exhaust E202 EF-E6 160 cfm 113 W ceiling exhaust fan
F.A.C.S. E107 Range
Exhaust
EF-E7 2800 cfm 1 hp belt drive roof exhauster
F.A.C.S. E107 Range
Exhaust
EF-E8 350 cfm 1/6 hp belt drive roof exhauster
Darkroom Exhaust EF-E9 95 cfm 80 W ceiling exhaust fan
Thunder Mountain High School 16 Energy Audit (January 2012)
Lighting
Interior lighting consists primarily of T8, T5, and compact fluorescent fixtures, and metal halide
lighting. Exterior lighting consists primarily of metal halide lighting. The interior lighting is
controlled by staff and the exterior lighting by a photocell. Lighting operational hours and subsequent
electrical demand are kept to a minimum.
Electric Equipment
Commercial kitchen equipment for food preparation at Thunder Mountain High School and five other
Juneau schools is located in the food prep area.
Thunder Mountain High School 17 Energy Audit (January 2012)
Section 5
Methodology
Information for the energy audit was gathered through on-site observations, review of construction
documents, and interviews with operation and maintenance personnel. The EEMs are evaluated using
energy and life cycle cost analyses and are priority ranked for implementation.
Energy Efficiency Measures
Energy efficiency measures are identified by evaluating the building’s energy systems and comparing
them to systems in modern, high performance buildings. The process for identifying the EEMs
acknowledges the realities of an existing building that was constructed when energy costs were much
lower. Many of the opportunities used in modern high performance buildings—highly insulated
envelopes, variable capacity mechanical systems, heat pumps, daylighting, lighting controls, etc.—
simply cannot be economically incorporated into an existing building.
The EEMs represent practical measures to improve the energy efficiency of the buildings, taking into
account the realities of limited budgets. If a future major renovation project occurs, additional EEMs
common to high performance buildings should be incorporated.
Life Cycle Cost Analysis
The EEMs are evaluated using life cycle cost analysis which determines if an energy efficiency
investment will provide a savings over a 25-year life. The analysis incorporates construction,
replacement, maintenance, repair, and energy costs to determine the total cost over the life of the
EEM. Future maintenance and energy cash flows are discounted to present worth using escalation
factors for general inflation, energy inflation, and the value of money. The methodology is based on
the National Institute of Standards and Technology (NIST) Handbook 135 – Life Cycle Cost
Analysis.
Life cycle cost analysis is preferred to simple payback for facilities that have long—often perpetual—
service lives. Simple payback, which compares construction cost and present energy cost, is
reasonable for short time periods of 2-4 years, but yields below optimal results over longer periods
because it does not properly account for the time value of money or inflationary effects on operating
budgets. Accounting for energy inflation and the time value of money properly sums the true cost of
facility ownership and seeks to minimize the life cycle cost.
Construction Costs
The cost estimates are derived based on a preliminary understanding of the scope of each EEM as
gathered during the walk-through audit. The construction costs for in-house labor are $60 per hour for
work typically performed by maintenance staff and $110 per hour for contract labor.
The cost estimate assumes the work will be performed as part of a larger renovation or energy
efficiency upgrade project. When implementing EEMs, the cost estimate should be revisited once the
scope and preferred method of performing the work has been determined. It is possible some EEMs
will not provide a life cycle savings when the scope is finalized.
Thunder Mountain High School 18 Energy Audit (January 2012)
Maintenance Costs
Maintenance costs are based on in-house or contract labor using historical maintenance efforts and
industry standards. Maintenance costs over the 25-year life of each EEM are included in the life cycle
cost calculation spreadsheets and represent the level of effort to maintain the systems.
Energy Analysis
The energy performance of an EEM is evaluated within the operating parameters of the building. A
comprehensive energy audit would rely on a computer model of the building to integrate building
energy systems and evaluate the energy savings of each EEM. This investment grade audit does not
utilize a computer model, so energy savings are calculated with factors that account for the dynamic
operation of the building. Energy savings and costs are estimated for the 25-year life of the EEM
using appropriate factors for energy inflation.
Prioritization
Each EEM is prioritized based on the life cycle savings to investment ratio (SIR) using the following
formula:
Prioritization Factor = Life Cycle Savings / Capital Costs
This approach factor puts significant weight on the capital cost of an EEM, making lower cost EEMs
more favorable.
Economic Factors
The following economic factors are significant to the findings.
Nominal Interest Rate: This is the nominal rate of return on an investment without regard to
inflation. The analysis uses a rate of 5%.
Inflation Rate: This is the average inflationary change in prices over time. The analysis uses an
inflation rate of 2%.
Economic Period: The analysis is based on a 25-year economic period with construction
beginning in 2010.
Fuel Oil
Fuel oil currently costs $3.80 per gallon for a seasonally adjusted blend of #1 and #2 fuel oil. The
analysis is based on 6% fuel oil inflation which has been the average for the past 20-years.
Thunder Mountain High School 19 Energy Audit (January 2012)
Electricity
Electricity is supplied by Alaska Electric Light & Power Company (AEL&P). The building is billed
for electricity under AEL&P’s Rate 24. This rate charges for both electrical consumption (kWh) and
peak electric demand (kW). Electrical consumption is the amount of energy consumed and electric
demand is the rate of consumption. AEL&P determines the electric demand by averaging demand
over a continuously sliding fifteen minute window. The highest fifteen minute average during the
billing period determines the peak demand. The following table lists the electric charges, which
includes a 24% rate hike that was recently approved:
AEL&P Small Government Rate with Demand
Charge 1 On-peak (Nov-May) Off-peak (June-Oct)
Energy Charge per kWh 6.11¢ 5.92¢
Demand Charge per kW $14.30 $9.11
Service Charge per month $99.24 $99.24
Over recent history, electricity inflation has been less than 1% per year, which has lagged general
inflation. An exception is the recent 24% rate hike that was primarily due to construction of additional
hydroelectric generation at Lake Dorothy. This project affords the community a surplus of power
which should bring electric inflation back to the historic rate of 1% per year. Load growth from
electric heat conversions is likely to increase generating and distribution costs, especially if diesel
supplementation is needed. Combining these two factors contribute to an assumed electricity inflation
rate of 3%.
Summary
The following table summarizes the energy and economic factors used in the analysis.
Summary of Economic and Energy Factors
Factor Rate or Cost Factor Rate or Cost
Nominal Discount Rate 5% Electricity Current rates
General Inflation Rate 2% Electricity Inflation 3%
Fuel Oil Cost (2012) $3.80/gal Fuel Oil Inflation 6%
Thunder Mountain High School 20 Energy Audit (January 2012)
Appendix A
Energy and Life Cycle Cost Analysis
Thunder Mountain High School 21 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
Basis
Economic
Study Period (years) 25 Nominal Discount Rate 5%General Inflation 2%
Energy
2011 $/gal Fuel Inflation 2012 $/gal
Fuel Oil $3.80 6% $4.03
Electricity $/kWh (2011)$/kW (2011)Inflation $/kWh (2012)$/kW (2012)
w/ Demand Charges $0.060 $12.14 3% $0.062 $12.50
w/o Demand Charges $0.103 -3% $0.106 -
EEM-2: Lower Entrance Temperature
Energy Analysis
Component Area R-value ΔT Hours MBH kBtu η boiler Gallons
Wall 203 19.0 -25 4,320 -0.3 -1,154 68%-12
Windows 297 1.5 -25 4,320 -5.0 -21,384 68%-227
Ceiling 154 40.0 -25 4,320 -0.1 -416 68%-4
Door 42 1.0 -25 4,320 -1.1 -4,536 68%-48
-6.4 -27,490 -292
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Turn down thermostat 0 1 LS $100 $100
Energy Costs
Fuel Oil 1 - 25 -292 gal $4.03 ($33,325)
Net Present Worth ($33,200)
EEM-3: Replace Aerators and Showerheads
Energy Analysis
η boiler 68%
Fixture Existing Proposed Uses/day Days Water,Gals % HW kBTU Gallons
Showerhead 20.0 10.0 25 180 -45,000 80% -24,019 -255
Lavatories 0.3 0.2 1,500 180 -48,600 80% -25,941 -275
-93,600 -530
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace lavatory aerators 0 75 ea $35 $2,625
Replace showerhead 0 9 ea $35 $315
Energy Costs
Water 1 - 25 -94 kgals $10.960 ($20,166)
Fuel Oil 1 - 25 -530 gal $4.03 ($60,487)
Net Present Worth ($77,700)
Gallons per Use
Thunder Mountain High School 22 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-4: Install Kiln Room Cooling
Energy Analysis
Fan Case CFM ΔP η, fan BHP η, motor kW Hours kWh
RTU-4 Supply -20,000 3.50 55% -20 93% -16 430 -6,907
Return -17,000 1.00 55%-5 93%-4 430 -1,677
-20 -8,584
Ventilation SA CFM MAT T,room MBH Hours kBtu η boiler Gallons
RTU-4 Existing -20,000 62 64 -43 430 -18,576 68%-197
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install automatic damper and controls 0 1 LS $3,500 $3,500
Project management 0 8%$280
Energy Costs
Electric Energy 1 - 25 -8,584 kWh $0.062 ($10,428)
Fuel Oil 1 - 25 -197 gal $4.03 ($22,519)
Net Present Worth ($29,200)
EEM-5: Reduce Infiltration / Optimize HVAC Systems
Energy Analysis
Fan Case CFM ΔP η, fan BHP η, motor kW Hours kWh
RF-6A Existing -24,000 0.90 55%-6 91%-5 1,620 -8,206
-5 -8,206
Ventilation SA CFM MAT T,room MBH Hours kBtu η boiler Gallons
RTU-2 Existing -27,000 55 65 -292 1,620 -472,392 68%-5,016
Optimized 20,250 62 65 66 1,620 106,288 68%1,129
AHU-3 Existing -16,000 60 65 -86 1,620 -139,968 68%-1,486
Optimized 12,000 62 65 39 1,620 62,986 68%669
AHU-7 Existing -25,000 55 65 -270 1,620 -437,400 68%-4,644
Optimized 12,500 63 65 27 1,620 43,740 68%464
RF-6A Existing -12,000 40 62 -285 1,620 -461,894 68%-4,904
-1,298,641 -13,789
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install IAQ OSA dampers 0 5 ea $10,000 $50,000
Balancing 0 1 LS $4,000 $4,000
Install VFD 0 1 LS $7,500 $7,500
Control modifications 0 1 LS $34,000 $34,000
Retro-commission 0 1 LS $20,000 $20,000
Estimating contingency 0 15% $17,325
Overhead & profit 0 30% $39,848
Design fees 0 10% $17,267
Project management 0 8% $15,195
Annual Costs
DDC Maintenance 1 - 25 1 LS $1,000.00 $17,027
Energy Costs
Electric Energy 1 - 25 -8,206 kWh $0.062 ($9,969)
Electric Demand 1 - 25 -61 kW $12.50 ($14,941)
Fuel Oil 1 - 25 -13,789 gal $4.03 ($1,574,306)
Net Present Worth ($1,377,100)
Thunder Mountain High School 23 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-6: Install Heat Recovery - Server Room E102
Energy Analysis
Heat Recovery
Input, MBH Hours Heat, kBtu Factor Recovery, kBtu η boiler Gallons
-60 6,480 -388,800 40% -155,520 82% -1,369
Heat Pump Energy
Recovery, kBtu COP kWh HP Heat, kBtu η boiler Gallons
-155,520 3 15,193 51,840 82% -456
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Ducted condensing unit 0 1 LS $7,000 $7,000
Ductwork amd grilles 0 1 LS $6,000 $6,000
Controls 0 1 LS $3,000 $3,000
Estimating contingency 0 15%$2,400
Overhead & profit 0 30%$5,520
Design fees 0 10%$2,392
Project management 0 8%$2,105
Energy Costs
Electric Energy 1 - 25 0 kWh $0.062 $0
Electric Demand 1 - 25 0.0 kW $12.50 $0
Fuel Oil 1 - 25 -1,826 gal $4.03 ($208,459)
Net Present Worth ($180,000)
EEM-7: Install Heat Recovery - Electric Room F207
Energy Analysis
Transformer
kVA % Load ηnew KW kWh Heat, kBtu η boiler Gallons
300 60% 98.9% -3.3 -17,345 -59,180 82% -521
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install circulation fan and ductwork 0 1 LS $5,200 $5,200
Estimating contingency 0 15%$780
Overhead & profit 0 30%$1,794
Design fees 0 10%$777
Project management 0 8% $684.11
Annual Costs
Filter maintenance 1 - 25 1 LS $100.00 $1,703
Energy Costs
Fuel Oil 1 - 25 -521 gal $4.03 ($59,494)
Net Present Worth ($48,600)
Thunder Mountain High School 24 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-8: Install Heat Recovery - Boiler Room
Energy Analysis
Heat Recovery
Input, MBH Jacket Loss MBH Hours Loss, kBtu Factor Recovery, kBtu η boiler Gallons
4,979 -1.0% -50 8,760 -436,160 75% -327,120 82%-2,880
Heat Pump Energy
Recovery, kBtu COP kWh HP Heat, kBtu η boiler Gallons
-327,120 3 31,958 109,040 82% -960
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Boiler room heat pump 0 1 LS $12,000 $12,000
Gym fan coil unit 0 1 LS $6,000 $6,000
Piping between heat pump and fan coil 0 1 LS $22,000 $22,000
Controls 0 1 LS $6,000 $6,000
Estimating contingency 0 15%$6,900
Overhead & profit 0 30% $15,870
Design fees 0 10%$6,877
Project management 0 8%$6,052
Annual Costs
Heat pump maintenance 1 - 25 1 LS $250.00 $4,257
Energy Costs
Electric Energy 1 - 25 31,958 kWh $0.062 $38,824
Electric Demand 1 - 25 60.0 kW $12.50 $14,748
Fuel Oil 1 - 25 -3,840 gal $4.03 ($438,472)
Net Present Worth ($298,900)
Thunder Mountain High School 25 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-9: Reduce Gym Lighting
Energy Analysis
Electric Savings
Fixture Number Hours Lamp Fixture Watts Lamp Fixture Watts kW kWh
Surface 79 2,600 6T5 373 4T5 248 -9.8 -25,511
-9.8 -25,511
Additional Heating Load
kWh Factor kBtu η boiler Gallons
25,511 33% 28,724 68% 305
Lamp Replacement
Type # Fixtures Lamp # Lamps Life, hrs Lamps//yr $/lamp Labor/lamp
Surface -79 2T5 2 36,000 -19 $12 $5.00
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Reprogram lighting control panel 0 1 LS $5,000 $5,000
Estimating contingency 0 15%$750
Overhead & profit 0 30%$1,725
Design fees 0 10%$748
Project management 0 8%$658
Annual Costs
Lamp replacement 1 - 25 -19 lamps $29.00 ($9,492)
Energy Costs
Electric Energy 1 - 25 -25,511 kWh $0.062 ($30,991)
Electric Demand 1 - 25 -118 kW $12.50 ($28,941)
Fuel Oil 1 - 25 305 gal $4.03 $34,821
Net Present Worth ($25,700)
EEM-10: Modify Unoccupied Heating Coil Controls
Energy Analysis
Component Area R-value ΔT MBH Hours kBtu η boiler Gallons
AHUs 2,352 12 -20 -3.9 5,040 -19,757 68%-210
RTUs 1,008 12 -20 -1.7 5,040 -8,467 68%-90
-5.6 -28,224 -300
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Modify heating coil controls 0 10 units $1,000 $10,000
Project management 0 8%$800
Energy Costs
Fuel Oil 1 - 25 -300 gal $4.03 ($34,215)
Net Present Worth ($23,400)
Existing Replacement Savings
Thunder Mountain High School 26 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-11: Convert Kitchen Hood to Variable Flow
Energy Analysis
Case CFM ΔP η, fan BHP η, motor kW Hours kWh
Existing -8,300 2.25 55%-5 93%-4 540 -2,314
Optimized 6,000 2.00 55%3 93%3 540 1,487
-1.5 -827
Ventilation SA CFM MAT T,room MBH Hours kBtu η boiler Gallons
Existing -8,300 40 68 -251 540 -135,536 68%-1,439
Optimized 4,150 40 68 125 540 67,768 68%720
-67,768 -720
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install VFD and controls 0 1 ea $7,500 $7,500
Kitchen hood control panel modification 0 1 LS $8,000 $8,000
Estimating contingency 0 15%$2,325
Overhead & profit 0 30%$5,348
Design fees 0 10%$2,317
Project management 0 8%$2,039
Energy Costs
Electric Energy 1 - 25 -827 kWh $0.062 ($1,005)
Fuel Oil 1 - 25 -720 gal $4.03 ($82,153)
Net Present Worth ($55,600)
EEM-12: Install Valves on Unit Heaters
Energy Analysis
Loss, BTUH Number Factor Loss, kBTU Boiler Effic Fuel, gals
-1,000 4 15% -5,256 68% -57
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install automatic valves and connect to fan wiring 0 4 ea $500 $2,000
Estimating contingency 0 15%$300
Overhead & profit 0 30%$690
Design fees 0 10%$299
Project management 0 8%$263
Energy Costs
Fuel Oil 1 - 25 -57 gal $4.03 ($6,537)
Net Present Worth ($3,000)
Thunder Mountain High School 27 Energy Audit (January 2012)
Alaska Energy Engineering LLC Energy and Life Cycle Cost Analysis
25200 Amalga Harbor Road Tel/Fax: 907.789.1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
EEM-13: Install Heat Recovery - Electric Room K106
Energy Analysis
Transformer
kVA % Load ηnew KW kWh Heat, kBtu η boiler Gallons
150 60% 98.9% -1.7 -8,672 -29,590 82% -261
Heat Pump Energy
Recovery, kBtu COP kWh HP Heat, kBtu η boiler Gallons
-29,590 3 2,891 9,863 82% -87
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install heat pump 0 1 LS $5,200 $5,200
Piping between heat pump and fan coil 0 1 LS $3,000 $3,000
Controls 0 1 LS $1,200 $1,200
Estimating contingency 0 15%$1,410
Overhead & profit 0 30%$3,243
Design fees 0 10%$1,405
Project management 0 8%$1,237
Annual Costs
HP Maintnenace 1 - 25 1 LS $200.00 $3,405
Energy Costs
Electric Energy 1 - 25 9,863 kWh $0.062 $11,982
Fuel Oil 1 - 25 -347 gal $4.03 ($39,663)
Net Present Worth ($7,600)
EEM-14: Upgrade Transformers
Energy Analysis
Number kVA ηold ηnew KW kWh
1 15 96.2% 98.1% -0.3 -2,497
3 30 96.8% 98.4% -1.4 -12,614
1 75 97.4% 98.7% -1.0 -8,541
3 150 97.8% 98.9% -5.0 -43,362
1 300 98.0% 99.0% -3.0 -26,280
-10.7 -93,294
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace transformer, kVA 15 0 1 LS $3,900 $3,900
Replace transformer, kVA 24 0 3 LS $4,400 $13,200
Replace transformer, kVA 45 0 1 LS $6,500 $6,500
Replace transformer, kVA 112.5 0 3 LS $12,400 $37,200
Replace transformer, kVA 225 0 1 LS $18,200 $18,200
Estimating contingency 0 15% $11,850
Overhead & profit 0 30% $27,255
Energy Costs
Electric Energy 1 - 25 -93,294 kWh $0.062 ($113,337)
Electric Demand 1 - 25 -128 kW $12.50 ($31,414)
Net Present Worth ($26,600)
Thunder Mountain High School 28 Energy Audit (January 2012)
Appendix B
Energy and Utility Data
Thunder Mountain High School 29 Energy Audit (January 2012)
Alaska Energy Engineering LLC Billing Data
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
ELECTRIC RATE
Electricity ($ / kWh )0.0611 0.0592
Demand ( $ / kW )14.30 9.11
Customer Charge ( $ / mo )99.24 99.24
Sales Tax ( % )0.0% 0.0%
ELECTRICAL CONSUMPTION AND DEMAND
kWh kW kWh kW kWh kW kWh kW
Jan 103,920 381.6 113,280 372.0 108,600
Feb 107,760 336.0 119,760 360.0 113,760
Mar 109,680 352.8 118,800 367.2 114,240
Apr 99,600 357.6 109,200 345.6 104,400
May 90,720 345.6 108,000 362.4 99,360
Jun 74,400 331.2 75,600 369.6 75,000
Jul 68,880 276.0 61,200 208.8 65,040
Aug 55,920 192.0 67,680 304.8 61,800
Sep 94,080 357.6 106,320 352.8 100,200
Oct 105,120 374.4 109,680 374.4 107,400
Nov 119,760 372.0 114,720 364.8 117,240
Dec 129,840 376.8 142,560 388.8 136,200
Total 1,159,680 1,246,800 1,203,240
Average 96,640 338 103,900 348 100,270
Load Factor 39.2%40.9%343
ELECTRIC BILLING DETAILS
Month Energy Demand Cust & Tax Total Energy Demand Cust & Tax Total % Change
Jan 6,350 5,457 99 11,906 6,921 5,320 99 12,340 3.7%
Feb 6,584 4,805 99 11,488 7,317 5,148 99 12,565 9.4%
Mar 6,701 5,045 99 11,846 7,259 5,251 99 12,609 6.4%
Apr 6,086 5,114 99 11,298 6,672 4,942 99 11,713 3.7%
May 5,543 4,942 99 10,584 6,599 5,182 99 11,880 12.2%
Jun 4,546 3,017 99 7,662 4,619 3,367 99 8,085 5.5%
Jul 4,209 2,514 99 6,822 3,739 1,902 99 5,741 -15.9%
Aug 3,417 1,749 99 5,265 4,135 2,777 99 7,011 33.2%
Sep 5,748 3,258 99 9,105 6,496 3,214 99 9,809 7.7%
Oct 6,423 3,411 99 9,933 6,701 3,411 99 10,211 2.8%
Nov 7,317 5,320 99 12,736 7,009 5,217 99 12,325 -3.2%
Dec 7,933 5,388 99 13,421 8,710 5,560 99 14,369 7.1%
Total $ 70,856 $ 50,020 $ 1,191 $ 122,067 $ 76,179 $ 51,290 $ 1,191 $ 128,661 5.4%
Average $ 5,905 $ 4,168 $ 99 $ 10,172 $ 6,348 $ 4,274 $ 99 $ 10,722 5.4%
Cost ($/kWh)$0.105 59% 40% 1% $0.103 -2.0%
Electrical costs are based on the current electric rates.
Average
2009 2010
2010
AEL&P Electric Rate 24 On-Peak
Nov-May
Off-peak
Jun-Oct
Month 2007 2008 2009
Thunder Mountain High School 30 Energy Audit (January 2012)
Alaska Energy Engineering LLC Annual Electric Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Use (kWh)Month of the Year
Electric Use History
2009
2010
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
450.0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Demand (kW)Month of the Year
Electric Demand History
2009
2010
Thunder Mountain High School 31 Energy Audit (January 2012)
Alaska Energy Engineering LLC Electric Cost
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School 2010
$ 0
$ 2,000
$ 4,000
$ 6,000
$ 8,000
$ 10,000
$ 12,000
$ 14,000
$ 16,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Cost (USD)Month of the Year
Electric Cost Breakdown
2010
Electric Use (kWh) Costs
Electric Demand (kW) Costs
Customer Charge and Taxes
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
450.0
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Electric Demand (kW)Electric Use (kWh)Month of the Year
Electric Use and Demand Comparison
2010
Electric Use
Electric Demand
Thunder Mountain High School 32 Energy Audit (January 2012)
Alaska Energy Engineering LLC Annual Fuel Oil Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
Year Fuel Oil Degree Days
2,007 9,282
2,008 9,093
2,009 65,637 9,284
2,010 55,590 9,013
5,000
6,000
7,000
8,000
9,000
10,000
30,000
35,000
40,000
45,000
50,000
55,000
60,000
65,000
70,000
2009 2010 Degree DaysGallons of Fuel OilYear
Annual Fuel Oil Use
Fuel Oil
Degree Days
Thunder Mountain High School 33 Energy Audit (January 2012)
Alaska Energy Engineering LLC Annual Water Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Thunder Mountain High School
Year Water
2,007
2,008
2,009 672,000
2,010 576,000
400,000
450,000
500,000
550,000
600,000
650,000
700,000
2009 2010Gallons of WaterYear
Annual Water Use
Thunder Mountain High School 34 Energy Audit (January 2012)
Alaska Energy Engineering LLC
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Annual Energy Consumption and Cost
Energy Cost $/MMBtu Area ECI EUI
Fuel Oil $3.80 $39.20 168,842 $2.10 73
Electricity $0.103 $31.84
Source Cost
Electricity 1,203,240 kWh $124,200 4,100 33%
Fuel Oil 60,614 Gallons $230,300 8,200 67%
Totals $354,500 12,300 100%
Annual Energy Consumption and Cost
Consumption Energy, MMBtu
$0
$5
$10
$15
$20
$25
$30
$35
$40
$45
Fuel Oil ElectricityCost $ / MMBtuCost of Heat Comparison
Thunder Mountain High School 35 Energy Audit (January 2012)
Appendix C
Equipment Data
Thunder Mountain High School 36 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficAC-1 MTR Room E102 EvaporatorLiebertMiniMate2 MMD60-COOLO5 Ton 1.5 HP/ 208 V/ ceiling mountedCondenserLiebertMiniMate2 PFC06705 Ton 208 Vroof mountedAS-1 Boiler Room K107 Air SepArmstrong VAS-10800 GPMAS-2 Boiler Room K107 Air SepArmstrong VAS-10800 GPMBLR-1 Boiler Room K107 BoilerWeil Mclain BL 168BR 4979 MBHBurnerWeishaugt L734.5 GPH 3.5 HP/ 460 VBLR-2 Boiler Room K107 BoilerWeil Mclain BL 168BR 4979 MBHBurnerWeishaugt L734.5 GPH 3.5 HP/ 460 VBLR-3 Boiler Room K107 BoilerWeil Mclain BL-98827.3 MBHBurnerWeishaugt L52 HP/ 460 VPMP-1 Boiler Room K107 Boiler 1 1/2 2 Circ Pump B&G Series 80 GF-3 350 GPM 5 HP/ 480 V/ 65%PMP-2 Boiler Room K107 Boiler 1 1/2 2 Circ Pump B&G Series 80 GF-3 350 GPM 5 HP/ 480 V/ 65%PMP-3 Boiler Room K107 Boiler 3 Circ Pump B&G Series 80 190 GPM 2 HP/ 480 V/ 63%PMP-4A Boiler Room K107 Secondary Loop Circ Pump B&GSeries 1531 3BC GE-3330 GPM 7.5 HP/ 480 V/ 72%PMP-4B Boiler Room K107 Secondary Loop Circ Pump B&GSeries 1531 3BC GE-3330 GPM 7.5 HP/ 480 V/ 72%PMP-4C Boiler Room K107 Secondary Loop Circ Pump B&GSeries 1531 3BC GE-3330 GPM 7.5 HP/ 480 V/ 72%Thunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make Model
Thunder Mountain High School 37 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelPMP-5A Boiler Room K107 Chilled H2O Cooling B&GSeries 1531 3BC GE-3400 GPM 15 HP/ 480 V/ 78%PMP-5B Boiler Room K107 Chilled H2O Cooling B&GSeries 1531 3BC GE-3400 GPM 15 HP/ 480 V/ 78%WP-1 Well Well Water Cooling Grundfos 475 S 400 GPM 50 HP/ 480 V/ 75%HX-1 Boiler Room K107 Heat Exhaust TranterGXD-051-H-5-OP-321770 GPM Chilled H2O 640 Well H2ORTU-1 Roof-Academic AHU HaakonSF1 Supply Fan 23,000 CFM 3Phase HP/ 480 VRF1 Return Fan 23,500 CFM 7.5 HP/ 480 VRTU-2 Roof-Academic AHU HaakonSF2 Supply Fan 27,000 CFM 30 HP/ 480 VRF2 Return Fan 25,500 CFM 7.5 HP/ 480 VAHU-3Fan Room 1 (Commons)AHU HaakonSF3 Supply Fan 16,000 CFM 20 HP/ 480 VRF3 Return Fan 12,000 CFM 5 HP/ 480 VRF38 Return Fan 4,000 CFM 1 HP/ 480 VRTU-4 Roof Core Arp. HaakonSF4 Supply Fan 27,000 CFM 40 HP/ 480 V
Thunder Mountain High School 38 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelRF4Return Fan27,000 CFM 10 HP/ 480 VAHU-5 Fan Room 2 Auditorium AHU HaakonSF5 Supply 26,000 CFM 15 HP/ 480 VRF5 Return 25,000 CFM 10 HP/ 480 VAHU-6 Fan Room 2 AHU-Music HaakonSF6 Supply 10,000 CFM 15 HP/ 480 VRF6A Return 6A 24,000 CFM 10 HP/ 480 VRF6B Return 6B 10,000 CFM 5 HP/ 480 VAHU-7 Fan Room 3 AHU-Main Gym HaakonSF7 Supply Fan 25,000 CFM 15 HP/ 480 VRF7A Return Fan 24,000 CFM 10 HP/ 480 VRF7B Return Fan 10,000 CFM 5 HP/ 480 VAHU-8 Fan Room 3 AHU- Auxiliary Gym HaakonSF8 Supply Fan 17,000 CFM 7.5 HP/ 480 VAHU-9 Fan Room 2 AHU Media Room Haakon 4,000 CFMSF9 Supply Fan 5 HP/ 480 V
Thunder Mountain High School 39 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelAHU-10 Boiler Room K107 AHU Boiler Room HaakonSF10 Supply Fan 6,500 CFM 3 HP/ 480 VCF-C1 Corridor C104 Electric Room Cooling Greenheck BCF-210-4 2000 CFM 1/4 HP/ 120 VCF-C2 Electric Room C208 Cooling Air Greenheck CSP-A410 200 CFM 121 W/ 120 VCF-D1 Corridor D115Electric Room D150 CoolingGreenheck BCF-210-4 2000 CFM 1/4 HP/ 120 VCF-D2Electric Room D21BCooling Air Greenheck CSP-A410 200 CFM 121 W/ 120 VCF-F1 Roof Electric Room F207 Greenheck GB-141-4 1200 CFM 1/4 HP/ 120 VEF-F1 Roof Area F Toilet Exhaust Greenheck GB-091-4 625 CFM 1/4 HP/ 120 VEF-F2 F202 Ceiling Media Toilet Exhaust Greenheck SP-B110 75 CFM 80 W/ 120 VEF-F3 Roof F111 Booth Vent Greenheck CUBE-141HP-7 800 CFM 3/4 HP/ 480 VEF-F4 Roof Art Table Exhaust Greenheck CUBE-141HP-7 1200 CFM 3/4 HP/ 480 VEF-F5 Roof Art Room Exhaust Greenheck CUBE-220HP-10 2700 CFM 1 HP/ 480 VEF-F6 Roof 3D Art Booth Vent Greenheck CUBE-141HP-7 800 CFM 3/4 HP/ 480 VEF-F7 F116 Ceiling Dryer Booth Exhaust Fantech DBF-100 120 CFM 78 W/ 120 VEF-F8 F116 Ceiling Range Hood Exhaust Fantech FX-10XL 350 CFM 242 W/ 120 VEF-G1 Roof Toilet Exhaust Greenheck GB-141-5 1275 CFM 1/2 HP/ 120 V
Thunder Mountain High School 40 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelEF-G2 G103 Ceiling Custodial Exhaust Greenheck 5P-B110 75 80 W/ 120 VEF-G3 Roof Tech Booth Vent Greenheck CUBE-141HP-7 800 CFM 3/4 HP/ 480 VEF-G4 Roof Shop Vent Booth Greenheck CUBE-141HP-7 800 CFM 3/4 HP/ 480 VEF-J1 Roof Women's Toilet Exhaust Greenheck GB-081-6 450 CFM 1/6 HP/ 120 VEF-J2 J102 Ceiling Dryer Exhaust Fantech DBF-110 120 CFM 78 W/ 120 VEF-K1 Roof Locker Room Exhaust Greenheck GB-220-5 3120 CFM 1/2 HP/ 120 VEF-K2 Roof Welding Exhaust Greenheck 7-IPA 1200 CFM 1.5 HP/ 480 VEF-K3 H110 Ceiling Custodial Exhaust Greenheck SP-A290 210 CFM 80 W/ 120 VEF-K4 Roof Electric Room K106 Greenheck GB-161HP-5 1800 CFM 1/2 HP/ 120 VEF-K5 Roof Small Engine Exhaust Greenheck GB-091-4 800 CFM 1/4 HP/ 120 VEF-K6 Roof Small Engine Booth Vent Greenheck CUBE-141HP-7 1050 CFM 3/4 HP/ 480 VEF-L1 Ceiling L117 Faculty Toilet Exhaust Greenheck SP-B110 75 CFM 80 W/ 120 VEF-L2 Ceiling L104 Toilet Exhaust Greenheck SP-B110 75 CFM 80 W/ 120 VEF-B1 Roof Toilet Exhaust Greenheck GB-081-6 300 CFM 1/6 HP/ 120 VEF-C1 Roof Toilet Exhaust Greenheck GB-141-3 1670 CFM 1/3 HP/ 120 VEF-C2 Roof Janitor Exhaust Greenheck GB-081-6 420 CFM 1/6 HP/ 120 V
Thunder Mountain High School 41 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelEF-C3 RoofScience Room Exhaust Greenheck GB-141-7 2400 CFM 3/4 HP/ 480 VEF-C4 RoofC219 Fume Hood Exhaust825 CFM 1/2 HP/ 120 VEF-C5 RoofC119 Fume Hood825 CFM 1/2 HP/ 120 VEF-C6 RoofC220 Fume Hood825 CFM 1/2 HP/ 120 VEF-C7 RoofC120 Fume Hood825 CFM 1/2 HP/ 120 VEF-D1 RoofToilet ExhaustGreenheck GB-141-3 1570 CFM 1/3 HP/ 120 VEF-D2 RoofJanitor ExhaustGreenheck GB-081-6 420 CFM 1/6 HP/ 120 VEF-D3 RoofScience Room Exhaust Greenheck GB-180HP-20 4000 CFM 2 HP/ 480 VEF-D4 RoofD202 Fume Hood825 CFM 1/2 HP/ 120 VEF-D5 RoofD103 Fume Hood825 CFM 1/2 HP/ 120 VEF-D6 RoofD205 Fume Hood825 CFM 1/2 HP/ 120 VEF-D7 RoofD105 Fume Hood825 CFM 1/2 HP/ 120 VEF-E1 RoofKitchen Hood H1 Greenheck CUBE-360XP-75 8300 CFM 7.5 HP/ 480 VEF-E2 RoofKitchen Hood H2 Greenheck CUBE-101-3 600 CFM 1/3 HP/ 120 VEF-E3 CeilingJanitor Exhaust E115 Greenheck SP-B110 75 CFM 80 W/ 120 VEF-E4 Kiln Room E119 Kiln ExhaustSkutt Envirovent 80 CFM 135 W/ 120 V
Thunder Mountain High School 42 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelEF-E5 Kiln Room E119 Kiln ExhaustSkutt Envirovent 80 CFM 135 W/ 120 VEF-E6 Ceiling E202 Janitor ExhaustGreenheck SP-A190 160 CFM 113W/ 120 VEF-E7 RoofE107 Range Exhaust Greenheck GB-141-10 2800 CFM 1 HP/ 480 VEF-E8 RoofE107 Range Exhaust Greenheck GB-081-6 360 CFM 1/6 HP/ 120 VEF-E9 Ceiling E212 Dark Room Exhaust Greenheck SP-B110 95 CFM 80 W/ 120 VT-10 AHU 7/8 Fan Room TransformerSquare D 15T3HFISLN 15 KVA 115 degrees C RiseNot TP-1 Rate 0WH-1 Boiler Room K107 Domestic Hot Water Pvi1250-900N 400A-TT0QWD400 gallon 1/2 HP/ 115 V/ 3450 RPMcombo fired/ indirect HW heaterWH-2 Boiler Room K107 Domestic Hot Water Pvi400N 400A-QWD 400 gallonindirect HW heaterCP-1 Boiler Room K107 DHW Recirculation B&G NBF-18S90 W/ 115 VCP-2 Boiler Room K107 DHW Circulation B&G TL-30B150 W/ 115 VT-9 Fan Room 2 Transformer T9Square D 30T3HFISLN 30 KVA 115 degrees C temp rise Not TP-1 RatedT-6 Fan Room 2 Transformer T6Square D EE500T681ISLN 500 KVA 150 degrees C tem riseNot TP-1 RatedGenerator Room Power Generation Cummins DFEJ-5785999 562.5 KVA 755 HPGensetT-7 Generator Room TransformerSquare D 30T3HFISLN 30 KVA 115 degrees C temp rise Not TP-1 RatedT-1 Electrical TransformerSquare D 150T3HFISNL 150 KVA 115 degrees C temp rise Not TP-1 RatedT-2 Fan Room 1 TransformerSquare D 75T3HFISNL 75 KVA 115 degrees C temp rise Not TP-1 Rated
Thunder Mountain High School 43 Energy Audit (January 2012)
MotorHP / Volts / RPM / EfficThunder Mountain High School - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelT-8 Fan Room 1 TransformerSquare D 30T3HFISLN 30 KVA 115 degrees C temp rise Not TP-1 RatedFan Room 1 Kitchen ChillerCold Zone CZ452AKitchenRefrigerator A2 HP/ 208 VKitchenRefrigerator B3 HP/ 208 VElevator Room ElevatorThyssen Krupp TAC 2025 HPT-5 Media Center Transformer T5Square D300 KVA 115 degrees C temp rise Not TP-1 RatedT-4 Classroom Wing D Transformer T4Square D150 KVA 115 degrees C temp rise Not TP-1 RatedT-3 Classroom Wing C Transformer T3Square D150 KVA 115 degrees C temp rise Not TP-1 Rated
Thunder Mountain High School 44 Energy Audit (January 2012)
Appendix D
Abbreviations
AHU Air handling unit
BTU British thermal unit
BTUH BTU per hour
CBJ City and Borough of Juneau
CMU Concrete masonry unit
CO2 Carbon dioxide
CUH Cabinet unit heater
DDC Direct digital controls
DHW Domestic hot water
EAD Exhaust air damper
EEM Energy efficiency measure
EF Exhaust fan
Gyp Bd Gypsum board
HVAC Heating, Ventilating, Air-
conditioning
HW Hot water
HWRP Hot water recirculating pump
KVA Kilovolt-amps
kW Kilowatt
kWh Kilowatt-hour
LED Light emitting diode
MBH 1,000 Btu per hour
MMBH 1,000,000 Btu per hour
OAD Outside air damper
PSI Per square inch
PSIG Per square inch gage
RAD Return air damper
RF Return fan
SIR Savings to investment ratio
SF Supply fan
UV Unit ventilator
VAV Variable air volume
VFD Variable frequency drive
Thunder Mountain High School 45 Energy Audit (January 2012)