HomeMy WebLinkAboutSEA-AEE-JNU Capital Transit Bus Barn 2012-EE
Capital Transit Bus Barn
City & Borough of Juneau
Funded by:
Final Report
November 2011
Prepared by:
Energy Audit
Table of Contents
Section 1: Executive Summary 2
Section 2: Introduction 6
Section 3: Energy Efficiency Measures 8
Section 4: Description of Systems 12
Section 5: Methodology 14
Appendix A: Energy and Life Cycle Cost Analysis 17
Appendix B: Energy and Utility Data 22
Appendix C: Equipment Data 29
Appendix D: Abbreviations 32
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
Capital Transit Bus Barn 1 Energy Audit (December 2011)
Section 1
Executive Summary
An energy audit of the Capital Transit Bus Barn 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.
Capital Transit Bus Barn is a 23,310 square foot building that contains offices, a break room,
mezzanine storage, a bus service bay, a bus storage bay, a bus washing bay, and mechanical support
spaces.
Building Assessment
The following summarizes our assessment of the building.
Envelope
The building is well insulated with the exception of the windows, doors, frames, and some insulation
damage. A major renovation that occurred after the CBJ purchased the building added insulation and
significantly improved the energy efficiency of the building envelope. The following additional
improvements can be made to the envelope:
Windows: The windows are double pane units but there is minimal spacing between the
panes and a large number of them are in steel frames. Both of these factors increase the
thermal conductivity of the window assembly. Future replacements can affordably triple the
R-value of the existing windows.
Exterior Doors: Exterior doors are not thermally broken. On the morning of the inspection
there was frost forming on the interior of the door frames. Future exterior door replacements
should be thermally broken. Weather stripping is in poor condition on both the man doors and
the overhead shop doors and should be replaced.
Wall & Ceiling Penetrations: The roof has several ductwork penetrations that are not
sealed. The walls have numerous conduit and piping penetrations that are not sealed. These
penetrations should be sealed and insulated.
Heating & Ventilation Systems
The building is heated by the following oil-fired forced air furnaces:
Two furnaces heat the office spaces
A combination fuel oil/waste oil furnace heats the service bay/ mezzanine area
A combination fuel oil/waste oil furnace is used as the back-up heat source to the bus storage
bay
A furnace heats the wash bay but was not operational at the time of the inspection.
The unit numbering designations shown on remodel drawings do not match the writing on the
furnaces, but are used for identifying equipment in this report.
Capital Transit Bus Barn 2 Energy Audit (December 2011)
With the exception of the new waste oil furnace in the bus storage bay, all of the forced air furnace
units appear to be approaching the end of their useful life and represent an opportunity to upgrade to
more efficient models. The furnaces in the service and storage bays are almost 20 years old and were
originally designed to utilize either waste oil or fuel oil. In addition to the inherent burner and heat
exchanger inefficiency of these units, they utilize inefficient motors to circulate the heated air
throughout the spaces.
The air quality in the office mechanical room is very poor. Fuel oil fumes persist due to interior oil
day tanks and inadequate ventilation. This air is being circulated by the forced air furnaces, impacting
the air quality in the offices. An upgrade to newer electric forced air furnaces utilizing the same
ducting would be a simple and cost effective approach to increase building efficiency and air quality.
Adding zone level electric heating coils will improve thermal comfort.
The newer fuel oil / waste oil furnace operates almost continuously throughout the winter to keep up
with the heating demand of the bus storage space. Because waste oil storage capacity is inadequate,
the furnace is also operated much of the summer, when the heat is not needed, to keep up with waste
oil generation. Installing additional waste oil storage will allow waste oil to collect during the summer
and be burned during the heating season, reducing the need to purchase fuel oil. Forecasting waste oil
generation and subsequent proper tank sizing to offset fuel oil purchases is an exercise that should be
undertaken to reduce unnecessary fuel oil expenses.
All of the spaces were utilizing manual thermostats for temperature control. The west and east office
wings were set at 72°F and 74°F respectively, and the service bay was set at 65°F. The addition of a
thermostat with automatic control features to allow a night setback of building temperatures in these
spaces will save energy.
The greatest heating load occurs when the overhead doors are open. The need to rotate 18 buses into
and out of a facility that only has room to store 12 buses requires the overhead doors to be opened
frequently. An operational and energy use analysis is recommended to measure the inefficiency of the
currently undersized storage facility againt a facility that is large enough to house all of the buses in
the fleet. In addition, the doors to the maintenance bay are often left open for extended periods. The
size of the overhead doors is quite large. When they are left open a considerable amount of heat is lost
through infiltration and convection. The greatest contribution that the occupants can have on energy
efficiency is to minimize the amount of time these doors are open. Automatic timers to close the
doors were used in the past with little success. New technology may offer renewed incentive to use
controls to minimize the number of hours the doors are open.
While replacing the furnaces will not provide sufficient savings to offset the replacement cost, other
improvements can be made to improve effectiveness and efficiency. These are outlined in Section 3,
Energy Efficiency Measures.
Lighting
Interior lighting consists primarily of T12 fluorescent fixtures, metal halide pendant fixtures, and high
pressure sodium wall packs. These are controlled by manual switches. Replacement of existing
fixtures with more efficient units and the addition of occupancy sensors are solutions for further
reductions in operational costs. However, much of the inefficient lighting supplies beneficial heat to
the building almost year-round in Juneau’s climate. Energy efficiency suggestions outlined in this
report for lighting systems take into account the value of the heat emitted by the existing lighting.
Exterior lighting consists primarily of high pressure sodium wall packs and metal halide parking lot
lighting. Exterior lighting is controlled by a photocell. The photocell is not adjusted properly and
lights were on during daylight hours.
Capital Transit Bus Barn 3 Energy Audit (December 2011)
Summary
It is the assessment of the energy audit team that the greatest energy inefficiency is the high number
of hours that the overhead doors are open. Other inefficiencies exist in the furnaces, lighting, and the
lack of programmable thermostats.
Energy Efficiency Measures (EEMs)
All buildings have opportunities to improve their energy efficiency. The energy audit revealed several
opportunities in which an efficiency investment will result in a net reduction in long-term operating
costs.
Behavioral and Operational EEMs
The following EEMs require behavioral and operational changes in the building use. The savings are
not readily quantifiable but these EEMs are highly recommended as low-cost opportunities that are a
standard of high performance buildings.
EEM-1: Weather-strip Doors
EEM-2: Proper Thermostat Setpoints
EEM-3: Optimize Waste Oil Use
High and Medium Priority EEMs
The following EEMs are recommended for investment. They are ranked by life cycle savings to
investment ratio (SIR). This ranking method places a priority on low cost EEMs which can be
immediately funded, generating energy savings to fund higher cost EEMs in the following years.
Negative values, in parenthesis, represent savings.
25 Year Life Cycle Cost Analysis
Investment Operating Energy Total SIR
High Priority
EEM-4: Install Programmable Thermostats $1,200 $0 ($39,400) ($38,200) 32.8
EEM-5: Replace Aerators and Showerheads $100 $0 ($3,000) ($2,900) 30.0
EEM-6: Perform Boiler Combustion Test $700 $24,500 ($32,800) ($7,600) 11.9
EEM-7: Install DHW Pipe Insulation $1,100 $0 ($5,200) ($4,100) 4.7
Medium Priority
EEM-8: Upgrade Service and Storage Bay Lighting $20,300 ($3,200) ($27,100) ($10,000) 1.5
EEM-9: Upgrade Exterior Lighting to LED $18,500 $600 ($28,000) ($8,900) 1.5
EEM-10: Upgrade Mezzanine Storage Bay Lighting $8,800 ($1,500) ($9,700) ($2,400) 1.3
EEM-11: Upgrade Transformers $25,900 $0 ($28,950) ($3,050) 1.1
Totals* $76,600 $20,400 ($174,150) ($77,150) 2.0
*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.
Capital Transit Bus Barn 4 Energy Audit (December 2011)
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.
Capital Transit Bus Barn 5 Energy Audit (December 2011)
Section 2
Introduction
This report presents the findings of an energy audit of the Capital Transit Bus Barn 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
Capital Transit Bus Barn is a 23,310 square foot building that contains offices, a break room,
mezzanine storage, a bus service bay, a bus storage bay, a bus washing bay, and mechanical support
spaces. The facility is occupied the following hours:
Monday to Saturday 6:00 am – Midnight
Sunday 8:00 am – 7:00pm
Building History
1974 – Original Construction
1984 – Purchased by City & Borough of Juneau
1985 – Major renovation by Dawson Construction
1989 – Entry Canopy Addition
1993 – Waste Oil Furnace
Capital Transit Bus Barn 6 Energy Audit (December 2011)
Energy Consumption
The building energy sources include an electric service, a fuel oil tank and waste oil. Fuel oil is used
for the majority of the heating loads, waste oil heats the storage bay, and electricity serves domestic
hot water and all other loads. The following table shows annual energy use and cost.
Annual Energy Consumption and Cost
Source Consumption Cost Energy, MMBtu
Electricity 183,145 kWh $21,000 600 21%
Waste Oil 2,386 Gallons $0 300 11%
Fuel Oil 13,841 Gallons $52,600 1,900 68%
Totals $73,600 2,800 100%
Electricity
The following chart shows electrical
energy use from 2007 to 2010. The
effective cost—energy costs plus
demand charges—is 11.5¢ per kWh.
Fuel and Waste Oil
The following chart shows heating energy
use from 2007 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.
Fuel oil use dropped after 2007 due to
installation of the waste oil furnace in the
storage bay.
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.
Capital Transit Bus Barn 7 Energy Audit (December 2011)
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 B 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.
Low Priority: EEMs that will save energy but do not provide a life cycle savings.
BEHAVIORAL OR OPERATIONAL
The following EEMs are recommended for implementation. They require behavioral or operational
changes that can occur with minimal investment to achieve immediate savings. These EEMs are not
easily quantified by analysis because they cannot be accurately predicted. They are recommended
because they offer a life cycle savings, represent good practice, and are accepted features of high
performance buildings.
EEM-1: Weather-strip Doors
Purpose: The exterior doors do not seal and are missing weather stripping. Energy will be saved if
doors are properly weather-stripped to reduce infiltration.
Scope: Replace weather stripping on exterior doors.
EEM-2: Proper Thermostat Setpoints
Purpose: The temperature in many of the rooms was much higher than needed for thermal comfort
during the intermittent periods workers are present. During the audit the temperature
setpoints in the office were 72°F for the west half and 74°F for the east half. The required
temperature should be assessed for each room. Rooms where the temperature can be
reduced will save heating energy.
Scope: Assess the required temperature in each room. Label the desired temperature setpoint on
each thermostat for the awareness of the occupants.
Capital Transit Bus Barn 8 Energy Audit (December 2011)
EEM-3: Optimize Waste Oil Use
Purpose: The bus storage overhead doors are kept open for extended periods for operational
reasons. There is tremendous heat loss during these periods. While the space is heated
with waste oil at little cost, if the doors were closed the waste oil could also heat other
areas of the building. There is also a need to install more waste oil storage capacity so
summer waste oil can be collected and burned during the heating season.
Scope: Optimize waste oil use by implementing the following measures:
- Modify operating procedures that leave the bus storage doors open for long periods.
- Install door controls that automatically operate the doors in response to bus
movement. The doors should also ventilate the space when indoor air quality is poor.
- Install more waste oil storage capacity so waste oil can be saved over the summer and
burned during the heating season.
- Convert the maintenance shop furnaces to burn waste oil.
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-4: Install Programmable Thermostats
Purpose: The building temperature and temperature of each shop bay is kept constant even though
the building is not occupied 24/7. Setting back the temperature during times the building
is unoccupied will reduce heating energy.
Scope: Install programmable thermostats and utilize a control strategy to turn down the
temperature during unoccupied periods.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($1,390) ($1,390) $1,200 $0 ($39,400) ($38,200) 32.8
EEM-5: Replace Aerators and Showerheads
Purpose: Energy and water will be saved by replacing showerheads and lavatory aerators with low-
flow models.
Scope: Replace showerheads and lavatory aerators with water-conserving fixtures.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($150) ($150) $100 $0 ($3,000) ($2,900) 30.0
Capital Transit Bus Barn 9 Energy Audit (December 2011)
EEM-6: Perform a Combustion Test
Purpose: Operating the fuel oil forced air furnaces with an optimum amount of excess air will
improve combustion efficiency. Annual cleaning followed by a combustion test is
recommended.
Scope: Annually clean and perform a combustion test on the forced air furnaces.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$1,440 ($1,160) $280 $700 $24,500 ($32,800) ($7,600) 11.9
EEM-7: Install DHW Pipe Insulation
Purpose: Portions of the DHW piping is uninsulated. Energy will be saved if these sections of
piping are optimally insulated.
Scope: Install pipe insulation.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($260) ($260) $1,100 $0 ($5,200) ($4,100) 4.7
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-8: Upgrade Service and Storage Bay Lighting
Purpose: Existing service and storage bay lighting utilizes 25 pendant-mounted metal halide
fixtures to light the space for approximately 119 hours per week. Energy will be saved if
the metal halide light fixtures are replaced with 6-bulb T5 units.
Scope: Replace metal halide lights with 6-bulb T5 units.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
($190) ($1,380) ($1,570) $20,300 ($3,200) ($27,100) ($10,000) 1.5
EEM-9: Upgrade Exterior Lighting to LED
Purpose: The exterior lighting consists of metal halide cobra head fixtures and high pressure
sodium wall packs. These fixture styles are less efficient than LED lighting and the lamp
life is much shorter.
Scope: Replace these existing exterior lights with LED lights.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$290 ($1,420) ($1,130) $18,500 $600 ($28,000) ($8,900) 1.5
Capital Transit Bus Barn 10 Energy Audit (December 2011)
EEM-10: Upgrade Mezzanine Storage Bay Lighting
Purpose: Existing service and storage bay lighting utilizes 12 pendant-mounted metal halide
fixtures to light the space for approximately 119 hours per week. Energy will be saved if
the metal halide light fixtures are replaced with 6-bulb T5 units.
Scope: Replace metal halide lights with 2-bulb T5 units.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
($90) ($490) ($580) $8,800 ($1,500) ($9,700) ($2,400) 1.3
EEM-11: Upgrade Transformers
Purpose: The transformers 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 NEMA Standard TP 1-2001compliant models.
Annual Costs Life Cycle Costs
Operating Energy Total Investment Operating Energy Total SIR
$0 ($1,470) ($1,470) $25,900 $0 ($28,950) ($3,050) 1.1
Capital Transit Bus Barn 11 Energy Audit (December 2011)
Section 4
Description of Systems
ENERGY SYSTEMS
This section provides a general description of the building systems. Energy conservation
opportunities are addressed in the Energy Efficiency Measure section of the report.
Building Envelope
The following table summarizes the existing envelope.
R-value
Component Description (inside to outside) Existing Optimal
Exterior Wall ½” gyp bd, 3” air space, 3” rigid foam, 3” batt, siding R-15 R-26
Roof 3” batt, metal roofing, 6” foam, metal roofing R-30 R-46
Floor Slab 8” Concrete slab-on-grade R-10 R-10
Foundation 8” concrete w/ 2” perimeter insulation board R-10 R-20
Windows Vinyl double pane windows (some w/ steel frame) R-1.25 R-5
Doors Steel doors w/ non-thermally broken frames R-1.5 R-5
Heating System
The building is heated by six forced-air fuel oil furnaces and one waste oil furnace.
Capital Transit Bus Barn 12 Energy Audit (December 2011)
Ventilation Systems
Area Fan System Description
Service Bay FAF-1 Dravo Corporation 450,000 BTU fuel oil & waste oil forced
air furnace
Bus Storage Bay FAF-2 Dravo Corporation 450,000 BTU fuel oil & waste oil forced
air furnace
West Offices FAF-3 Lennox 97,000 BTU fuel oil forced air furnace
East Offices FAF-4 Lennox fuel oil forced air furnace
Wash Bay FAF-5 100,000 BTU Modine fuel oil forced air furnace
Bus Storage Bay FAF-6 170,000 BTU Clean Burn waste oil heater
General Service Bay EF-1 Constant volume exhaust air fan
Vehicle Exhaust EF-3 Constant volume exhaust air fan
Welding Table/Shot Blaster EF-4 Constant volume exhaust air fan
General Service Bay EF-5 Constant volume exhaust air fan
Women’s Toilet Area EF Constant volume exhaust air fan
Women’s Shower Area EF Constant volume exhaust air fan
Men’s Toilet Area EF Constant volume exhaust air fan
Men’s Shower Area EF Constant volume exhaust air fan
Domestic Hot Water System
The domestic hot water system consists of a single 120 gallon, 15 kW Rudd domestic hot water
heater that is located in the storage mezzanine. The supply piping from the domestic hot water heater
is not insulated.
Lighting
Interior lighting consists primarily of T12 fluorescent fixtures, metal halide pendant fixtures, and high
pressure sodium wall packs. These are controlled by manual switches. Replacement of existing
fixtures with more efficient units and the addition of occupancy sensors are solutions for further
reductions in operational costs. However, much of the inefficient lighting supplies beneficial heat to
the building almost year-round in Juneau’s climate. Energy efficiency suggestions outlined in this
report for lighting systems take into account the value of the heat emitted by the existing lighting.
Exterior lighting consists primarily of high pressure sodium wall packs and metal halide parking lot
lighting. Exterior lighting is controlled by a photocell. The photocell is not adjusted properly and
lights were on during daylight hours.
Electric Equipment
Additional electrical equipment for the support of bus maintenance is located in the bus service bay.
Capital Transit Bus Barn 13 Energy Audit (December 2011)
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 and 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.
Capital Transit Bus Barn 14 Energy Audit (December 2011)
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.
Capital Transit Bus Barn 15 Energy Audit (December 2011)
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 $0.111/kWh
General Inflation Rate 2% Electricity Inflation 3%
Fuel Oil Cost (2012) $3.80/gal Fuel Oil Inflation 6%
Capital Transit Bus Barn 16 Energy Audit (December 2011)
Appendix A
Energy and Life Cycle Cost Analysis
Capital Transit Bus Barn 17 Energy Audit (December 2011)
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
Capital Transit Bus Barn
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 $0.102 -3% $0.105 -
EEM-4: Install Programmable Thermostats
Energy Analysis
Annual Gal % Savings Savings, Gal
11,500 -3.0% -345
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Install programmavble thermostat 0 6 LS $200 $1,200
Energy Costs
Fuel Oil 1 - 25 -345 gal $4.03 ($39,389)
Net Present Worth ($38,200)
EEM-5: Replace Aerators and Showerheads
Energy Analysis
Fixture Existing Proposed Uses/day Days Water,Gals % HW kBTU kWh
Showerhead 20.0 10.0 1 360 -3,600 80% -1,922 -563
Lavatories 0.3 0.2 30 360 -1,944 80% -1,038 -304
-5,544 -867
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace lavatory aerators 0 2 ea $35 $70
Replace showerhead 0 2 ea $35 $70
Energy Costs
Water 1 - 25 -6 kgals $10.960 ($1,194)
Electric Energy (Effective Cost)1 - 25 -867 kWh $0.105 ($1,791)
Net Present Worth ($2,800)
Gallons per Use
Capital Transit Bus Barn 18 Energy Audit (December 2011)
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
Capital Transit Bus Barn
EEM-6: Perform Boiler Combustion Test
Energy Analysis
Annual Gal % Savings Savings, Gal
11,500 -2.5% -288
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Purchase combustion analyzer 0 1 LS $700 $700
Annual Costs
Clean and Combustion test 1 - 25 24 hrs $60.00 $24,519
Energy Costs
Fuel Oil 1 - 25 -288 gal $4.03 ($32,824)
Net Present Worth ($7,600)
EEM-7: Install DHW Pipe Insulation
Energy Analysis
Service Size Length Bare BTUH Insul BTUH Factor kBtu kWh
DHW 0.75 125 25 4 33% -7,588 -2,224
DHW 1.25 10 38 5 33% -954 -280
-2,504
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Pipe Insulation 3/4"0 125 lnft $5 $625
1-1/4"0 10 lnft $7 $70
Overhead & profit 0 30%$209
Design fees 0 10%$90
Project management 0 8%$80
Energy Costs
Electric Energy (Effective Cost)1 - 25 -2,504 kWh $0.105 ($5,171)
Net Present Worth ($4,100)
Capital Transit Bus Barn 19 Energy Audit (December 2011)
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
Capital Transit Bus Barn
EEM-8: Upgrade Service and Storage Bay Lighting
Energy Analysis
Lamp Lamp, watts Fixture Watts Lamp Lamp, watts Fixture Watts kW Hours kWh
MH 400 460 T5 310 357 -2.6 6,188 -16,011
Lamp Replacement
# Fixtures Lamp # Lamps Life, hrs Replace/yr $/lamp replace
25 MH -1 20,000 -7.74 $30
25 T5 6 30,000 5.16 $24
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace 400 watt MH with T5 Fluorescent 0 25 LS $525 $13,125
Overhead & profit 0 30%$3,938
Design fees 0 10%$1,706
Project management 0 8%$1,502
Annual Costs
Existing lamp replacement, 400 watt MH 1 - 25 -7.74 replacements $60.00 ($7,902)
New lamp replacement, T5 1 - 25 5.16 replacements $54.00 $4,741
Energy Costs
Electric Energy 1 - 25 -16,011 kWh $0.062 ($19,451)
Electric Demand 1 - 25 -31 kW $12.50 ($7,632)
Net Present Worth ($10,000)
EEM-9: Upgrade Exterior Lighting to LED
Energy Analysis
Type # Fixtures Lamp Lamp, watts Fixture Watts Lamp Lamp, watts Fixture Watts Savings, kWh
WallPak 11 HPS 175 201 LED -90 -5,360
Cobra Head 13 HPS 400 460 LED -150 -17,651
-23,011
Lamp Replacement
Type # Fixtures Lamp # Lamps Life, hrs Lamps//yr $ / lamp $ / Replace
WallPak 11 HPS -1 24,000 -2.01 $40 $20
Cobra Head 13 HPS -1 24,000 -2.37 $50 $60
WallPak 11 LED 1 60,000 0.80 $190 $20
Cobra Head 13 LED 1 60,000 0.95 $200 $60
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace WallPak: 175 watt HPS with LED 0 11 LS $525 $5,775
Replace Cobra Head: 400 watt HPS with LED 1 13 LS $900 $11,366
Project management 0 8%$1,371
Annual Costs
Existing lamp replacement, 150 watt HPS 1 - 25 -2.01 lamps $60.00 ($2,051)
Existing lamp replacement, 250 watt HPS 1 - 25 -2.37 lamps $110.00 ($4,444)
LED board replacement, 80 watts 1 - 25 0.80 LED board $210.00 $2,871
LED board replacement, 106 watts 1 - 25 0.95 LED board $260.00 $4,201
Energy Costs
Electric Energy 1 - 25 -23,011 kWh $0.062 ($27,955)
Net Present Worth ($8,900)
Existing Replacement Savings
Existing Replacement
Fixtures
25
Capital Transit Bus Barn 20 Energy Audit (December 2011)
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
Capital Transit Bus Barn
EEM-10: Upgrade Mezzanine Storage Bay Lighting
Energy Analysis
Lamp Lamp, watts Fixture Watts Lamp Lamp, watts Fixture Watts kW Hours kWh
MH 175 201 T5 108 124 -0.9 6,188 -5,721
Lamp Replacement
# Fixtures Lamp # Lamps Life, hrs Replace/yr $/lamp replace
12 MH -1 20,000 -3.71 $30
12 T5 2 30,000 2.48 $24
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace 400 watt MH with T5 Fluorescent 0 12 LS $475 $5,700
Overhead & profit 0 30%$1,710
Design fees 0 10%$741
Project management 0 8%$652
Annual Costs
Existing lamp replacement, 400 watt MH 1 - 25 -3.71 replacements $60.00 ($3,793)
New lamp replacement, T5 1 - 25 2.48 replacements $54.00 $2,276
Energy Costs
Electric Energy 1 - 25 -5,721 kWh $0.062 ($6,951)
Electric Demand 1 - 25 -11 kW $12.50 ($2,727)
Net Present Worth ($2,400)
EEM-11: Upgrade Transformers
Energy Analysis
Number kVA ηold ηnew KW kWh
1 30 96.8% 98.4% -0.5 -4,205
1 150 97.8% 98.9% -1.7 -14,454
-2.1 -18,659
Life Cycle Cost Analysis Year Qty Unit Base Cost Year 0 Cost
Construction Costs
Replace transformer, kVA 24 0 1 LS $4,400 $4,400
Replace transformer, kVA 112.5 0 1 LS $12,400 $12,400
Overhead & profit 0 30%$5,040
Design fees 0 10%$2,184
Project management 0 8%$1,922
Energy Costs
Electric Energy 1 - 25 -18,659 kWh $0.062 ($22,667)
Electric Demand 1 - 25 -26 kW $12.50 ($6,283)
Net Present Worth ($3,000)
12
Existing Replacement Savings
Fixtures
Capital Transit Bus Barn 21 Energy Audit (December 2011)
Appendix B
Energy and Utility Data
Capital Transit Bus Barn 22 Energy Audit (December 2011)
Alaska Energy Engineering LLC Billing Data
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Capital Transit Bus Barn
ELECTRIC RATE
Electricity ($ / 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 16,760 60.80 17,440 57.60 17,480 58.00 15,640 58.70 16,830
Feb 18,600 59.20 19,400 55.20 18,480 62.00 14,730 61.40 17,803
Mar 16,280 51.20 17,960 60.80 6,160 52.80 14,740 53.40 13,785
Apr 16,320 54.80 16,960 57.20 15,420 52.50 16,510 56.30 16,303
May 16,760 54.00 12,800 52.80 15,520 52.50 14,620 61.10 14,925
Jun 16,480 51.20 9,360 44.80 13,130 56.00 12,490 51.20 12,865
Jul 15,040 60.40 12,280 50.80 13,060 50.90 13,850 47.60 13,558
Aug 17,400 51.20 14,800 48.40 14,150 52.60 13,530 48.20 14,970
Sep 15,080 50.00 13,040 46.00 13,630 50.00 13,730 56.10 13,870
Oct 16,800 51.60 14,760 54.00 14,630 49.80 15,370 54.50 15,390
Nov 18,680 52.80 16,680 55.20 14,680 56.20 14,630 60.70 16,168
Dec 18,160 59.20 16,720 55.20 15,990 53.90 15,850 61.90 16,680
Total 202,360 182,200 172,330 175,690 183,145
Average 16,863 55 15,183 53 14,361 54 14,641 56 15,262
Load Factor 42.2%39.1%36.5%35.9%54
ELECTRIC BILLING DETAILS
Month Energy Demand Cust & Tax Total Energy Demand Cust & Tax Total % Change
Jan $1,068 $829 $99 $1,997 $956 $839 $99 $1,894 -5.1%
Feb $1,129 $887 $99 $2,115 $900 $878 $99 $1,877 -11.2%
Mar $376 $755 $99 $1,231 $901 $764 $99 $1,763 43.3%
Apr $942 $751 $99 $1,792 $1,009 $805 $99 $1,913 6.7%
May $948 $751 $99 $1,798 $893 $874 $99 $1,866 3.8%
Jun $802 $510 $99 $1,412 $763 $466 $99 $1,329 -5.9%
Jul $798 $464 $99 $1,361 $846 $434 $99 $1,379 1.3%
Aug $865 $479 $99 $1,443 $827 $439 $99 $1,365 -5.4%
Sep $833 $456 $99 $1,388 $839 $511 $99 $1,449 4.4%
Oct $894 $454 $99 $1,447 $939 $496 $99 $1,535 6.1%
Nov $897 $804 $99 $1,800 $894 $868 $99 $1,861 3.4%
Dec $977 $771 $99 $1,847 $968 $885 $99 $1,953 5.7%
Total $ 10,529 $ 7,909 $ 1,191 $ 19,629 $ 10,735 $ 8,260 $ 1,191 $ 20,185 2.8%
Average $ 877 $ 659 $ 99 $ 1,636 $ 895 $ 688 $ 99 $ 1,682 2.8%
Cost ($/kWh)$0.114 53% 41% 6% $0.115 0.9%
Electrical costs are based on the current electric rates.
2009 2010
2010
AEL&P Electric Rate 24 On-Peak
Nov-May
Off-peak
Jun-Oct
Month 2007 2008 2009 Average
Capital Transit Bus Barn 23 Energy Audit (December 2011)
Alaska Energy Engineering LLC Annual Electric Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Capital Transit Bus Barn
0
5,000
10,000
15,000
20,000
25,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Use (kWh)Month of the Year
Electric Use History
2007
2008
2009
2010
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecElectric Demand (kW)Month of the Year
Electric Demand History
2007
2008
2009
2010
Capital Transit Bus Barn 24 Energy Audit (December 2011)
Alaska Energy Engineering LLC Electric Cost
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Capital Transit Bus Barn 2010
$ 0
$ 500
$ 1,000
$ 1,500
$ 2,000
$ 2,500
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
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
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
Capital Transit Bus Barn 25 Energy Audit (December 2011)
Alaska Energy Engineering LLC Annual Fuel Oil Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Capital Transit Bus Barn
Year Fuel Oil Degree Days
2,007 21,422 9,282
2,008 15,088 9,093
2,009 12,701 9,284
2,010 13,733 9,013
5,000
6,000
7,000
8,000
9,000
10,000
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
20,000
22,000
24,000
26,000
2007 2008 2009 2010 Degree DaysGallons of OilYear
Annual Fuel Oil and Waste Oil Use
Fuel Oil
Degree Days
Capital Transit Bus Barn 26 Energy Audit (December 2011)
Alaska Energy Engineering LLC Annual Water Consumption
25200 Amalga Harbor Road Tel/Fax: 907-789-1226
Juneau, Alaska 99801 jim@alaskaenergy.us
Capital Transit Bus Barn
Year Water
2,007 360,000
2,008 192,000
2,009 180,000
2,010 204,000
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
2007 2008 2009 2010Gallons of WaterYear
Annual Water Use
Capital Transit Bus Barn 27 Energy Audit (December 2011)
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 23,310 $3.16 120
Electricity $0.115 $35.45
Source Cost
Electricity 183,145 kWh $21,000 600 21%
Waste Oil 2,386 Gallons $0 300 11%
Fuel Oil 13,841 Gallons $52,600 1,900 68%
Totals $73,600 2,800 100%
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
Capital Transit Bus Barn 28 Energy Audit (December 2011)
Appendix C
Equipment Data
Capital Transit Bus Barn 29 Energy Audit (December 2011)
MotorHP / Volts / RPM / EfficFAF 3 Mechanical Room Office West Lennox 023Q4-105/120-4A 97 MBHFAF 4 Mechanical Room Office East Lennox 012-70Mezzaine Gen Set ONAN 25 25 KWMezzaine Hot Water RUUD EGLS120-15-Q 120 Gallon 480 V/ 15 KWMezzaine Transformer Square D 35149-17232-010 150 KVA 480-208VMezzaine Transformer Square D 33349-17232-012 30 KVA 408-208VFAF 6 Bus Bay Space Heater Clean Burn CB1750 170 MBH Waste Oil BurnerShop Bay Compressor Doerr 900-10-B 5 HP/ 440 V/ 1740 rpm/83.3Shop Bay Compressor Campbell 6-350193-01 10 HP/ 230-460 V/ 1750 rpm/85.7%HausfeldFAF 1 Shop Bay Dravo Corp. Dravo Corp. 45WO 450 MBH 1 HP/ 115 V/76% West EndFAF 2 Shop Bay Bus Barn Dravo Corp. 45 WO 450 MBH 1 HP/ 115 V/76% East EndSF 1 Shop Bay Space Supply AirEF 1 Shop Bay Space Exhaust 7 1/2 HP/ 460 V/ 1760 rpm/ 80%EF 3 Shop Bay Vehicle EshaustEF 4 Shop Bay Welding TableEF 5 Shop Bay General ExhaustWash Bay Hydrolic Pump 15 HP/ 480 V/ 82.5%Wash Bay Rinse Pump 10 HP/ 460 V/ 89 %Wash Bay Wash Pump 10 HP/ 460 V/ 89.5%FAF 5 Wash Bay Modine POR100B 100 MBH Not operatingCapital Transit Bus Barn - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make Model
Capital Transit Bus Barn 30 Energy Audit (December 2011)
MotorHP / Volts / RPM / EfficCapital Transit Bus Barn - Major Equipment InventoryCapacityNotesUnit IDLocation Function Make ModelEF 8A Womens RR Toilet Exhaust100 CFM 1/4 HP/47%EF 8B Mens RR Toilet Exhaust100 CFM 1/4 HP/47%EF 7 Mens RR Shower Exhaust100 CFM 1/4 HP/47%EF 6 Womens RR Shower Exhaust100 CFM 1/4 HP/47%
Capital Transit Bus Barn 31 Energy Audit (December 2011)
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
Capital Transit Bus Barn 32 Energy Audit (December 2011)