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Home My WebLink AboutHCR Holy Cross K12 School 2012-EEManaging Office 2400 College Road 3105 Lakeshore Dr. Suite 106A 4402 Thane Road Fairbanks, Alaska 99709 Anchorage, Alaska 99517 Juneau, Alaska 99801 p. 907.452.5688 p. 907.222.2445 p: 907.586.6813 f. 907.452.5694 f. 907.222.0915 f: 907.586.6819 www.nortechengr.com ENERGY AUDIT – FINAL REPORT Holy Cross K12 School P.O. Box 90 Holy Cross, Alaska Prepared for: Mr. Steve Graham Director of Maintenance and Facilities Iditarod Area School District P.O. Box 90 McGrath, Alaska Prepared by: David C. Lanning PE, CEA Pauline E. Fusco EIT, CEAIT Jason Ginter CEA July 10, 2012 Acknowledgment: "This material is based upon work supported by the Department of Energy under Award Number DE-EE0000095.” ENVIRONMENTAL ENGINEERING, HEALTH & SAFETY Anch: 3105 Lakeshore Dr. Ste 106A, 99517 907.222.2445 Fax: 222.0915 Fairbanks: 2400 College Road, 99709 907.452.5688 Fax: 452.5694 Juneau: 4402 Thane Road, 99801 907.586.6813 Fax: 586.6819 info@nortechengr.com www.nortechengr.com F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx i TABLE OF CONTENTS 1.0 EXECUTIVE SUMMARY ................................................................................................. 1 2.0 INTRODUCTION ............................................................................................................. 4 2.1 Building Use ......................................................................................................... 4 2.2 Building Occupancy and Schedules ..................................................................... 4 2.3 Building Description ............................................................................................. 4 3.0 BENCHMARKING 2010 UTILITY DATA ......................................................................... 7 3.1 Total Energy Use and Cost of 2010 ..................................................................... 8 3.2 Energy Utilization Index of 2010 ........................................................................... 9 3.3 Cost Utilization Index of 2010............................................................................. 10 3.4 Seasonal Energy Use Patterns .......................................................................... 11 3.5 Future Energy Monitoring ................................................................................... 12 4.0 MODELING ENERGY CONSUMPTION ........................................................................ 13 4.1 Understanding How AkWarm Models Energy Consumption ............................... 14 4.2 AkWarm Calculated Savings for the Holy Cross K12 School ............................. 15 4.3 Additional Modeling Methods ............................................................................. 16 5.0 BUILDING OPERATION AND MAINTENANCE (O & M) .............................................. 17 5.1 Operations and Maintenance ............................................................................. 17 5.2 Commissioning .................................................................................................. 17 5.3 Building Specific Recommendations .................................................................. 17 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx ii APPENDICES Appendix A Recommended Energy Efficiency Measures .......................................... 20 Appendix B Energy Efficiency Measures that are NOT Recommended ..................... 24 Appendix C Significant Equipment List ...................................................................... 26 Appendix D Local Utility Rate Structure ..................................................................... 27 Appendix E Analysis Methodology ............................................................................ 28 Appendix F Audit Limitations ..................................................................................... 29 Appendix G References ............................................................................................. 30 Appendix H Typical Energy Use and Cost – Fairbanks and Anchorage ..................... 31 Appendix I Typical Energy Use and Cost – Continental U.S. ................................... 32 Appendix J List of Conversion Factors and Energy Units .......................................... 33 Appendix K List of Acronyms, Abbreviations, and Definitions .................................... 34 Appendix L Building Floor Plan ................................................................................. 35 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 1 1.0 EXECUTIVE SUMMARY NORTECH has completed an ASHRAE Level II Energy Audit of the Holy Cross K12 School, a 19,580 square foot facility in the Iditarod Area school district. The audit began with benchmarking which resulted in a calculation of the energy consumption per square foot. A site inspection was completed on March 10th and 11th, 2012 to obtain information about the lighting, heating, ventilation, cooling and other building energy uses. The existing usage data and current systems were then used to develop a building energy consumption model using AkWarm. Once the model was calibrated, a number of Energy Efficiency Measures (EEMs) were developed from review of the data and observations. EEMs were evaluated and ranked on the basis of both energy savings and cost using a Savings/Investment Ratio (SIR). While these modeling techniques were successful in verifying that many of the EEMs would save energy, not all of the identified EEMs were considered cost effective based on the hardware, installation, and energy costs at the time of this audit. While the need for a major retrofit can typically be identified by an energy audit, upgrading specific systems often requires collecting additional data and engineering and design efforts that are beyond the scope of the Level II energy audit. The necessity and amount of design effort and cost will vary depending on the scope of the specific EEMs planned and the sophistication and capability of the entire design team, including the building owners and operators. During the budgeting process for any major retrofit identified in this report, the building owner should add administrative and supplemental design costs to cover the individual needs of their own organization and the overall retrofit project. The recommended EEMs for the Holy Cross K12 School are summarized in the table below. Additional discussion of the modeling process can be found in Section 3. Details of each individual EEM can be found in Appendix A of this report. A summary of EEMs that were evaluated but are not currently recommended is located in Appendix B. PRIORITY LIST – ENERGY EFFICIENCY MEASURES (EEMs) Rank Feature/ Location Improvement Description Estimated Annual Energy Savings Estimated Installed Cost Savings to Investment Ratio, SIR Simple Payback (Years) 1 Setback Thermostat: Main Install approximately 15 programmable thermostats and implement a heating temperature unoccupied and night-time setback to 60° F. $8,265 $4,500 24 0.5 2 Lighting Remove peripheral lobby lighting, replace incandescent lighting with 13W CFL spirals. $792 $600 8.4 0.8 3 Plug Loads Remove space heaters, humidifiers and mini-fridges from classrooms. Replace glass-front refrigerators with Energy Star full-size refrigerators. $1,096 $2,700 2.6 2.5 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 2 PRIORITY LIST – ENERGY EFFICIENCY MEASURES (EEMs) Rank Feature/ Location Improvement Description Estimated Annual Energy Savings Estimated Installed Cost Savings to Investment Ratio, SIR Simple Payback (Years) 4 HVAC And DHW Replace primary heating circulation pumps with Grundfos Magna or Alpha circulation pumps, or equivalent, which will result in savings of at least 50% due to improved motor design. $4,488 $15,000 2.4 3.3 5 On- or Below- Grade Floor, Perimeter: Crawlspace and Basement Install R-30 Encapsulated Fiberglass Batts on the Perimeter 4 feet of the Crawl Space Floor. $837 $11,155 1.8 13 TOTAL, cost-effective measures $15,480 $33,955 3.0 2.2 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 3 Modeled Building Energy Cost Breakdown The above charts are a graphical representation of the modeled energy usage for the Holy Cross K12 School. The greatest portions of energy cost for the building are envelope air losses and lighting. Detailed improvements can be found in Appendix A. The energy cost by end use breakdown was provided by AkWarm based on the field inspection and does not indicate that all individual fixtures and appliances were directly measured. The current energy costs are shown above on the left hand pie graph and the projected energy costs, assuming use of the recommended EEMs, are shown on the right. The chart breaks down energy usage by cost into the following categories: • Envelope Air Losses—the cost to provide heated fresh air to occupants, air leakage, heat lost in air through the chimneys and exhaust fans, heat lost to wind and other similar losses. • Envelope o Ceiling—quantified heat loss transferred through the ceiling portion of the envelope. o Window—quantified heat loss through the window portion of the envelope. o Wall/Door—quantified heat loss through the wall and door portions of the envelope. o Floor—quantified heat loss through the floor portion of the envelope. • Water Heating—energy cost to provide domestic hot water. • Fans—energy cost to run ventilation, and exhaust fans. • Lighting—energy cost to light the building. • Refrigeration—energy costs to provide refrigerated goods for the occupants. • Other Electrical—includes energy costs not listed above including cooking loads, laundry loads, other plug loads and electronics. Envelope Air Losses $22,024 25% Ceiling $8,009 9% Window $7,007 8% Wall/Door $11,012 13% Floor $10,011 12% Water Heating $2,060 2% Fans $38 0% Lighting $18,040 21% Refriger- ation $4,399 5% Other Electrical $4,318 5% Existing Building Energy Cost $86,918 Envelope Air Losses $17,012 20% Ceiling $7,005 8% Window $5,004 6% Wall/Door $9,007 10% Floor $7,255 8% Water Heating $2,060 2% Fans $38 0% Lighting $16,895 19% Refriger- ation $3,127 4% Other Electrical $4,034 5% EEM Savings $15,480 18% Retrofit Building Energy Cost $71,438 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 4 2.0 INTRODUCTION The Alaska Housing Finance Corporation contracted with NORTECH to perform ASHRAE Level II Energy Audits for publically owned buildings in Alaska. This report presents the findings of the utility benchmarking, modeling analysis, and the recommended building modifications, and building use changes that are expected to save energy and money. The report is organized into sections covering: • description of the facility, • the building’s historic energy usage (benchmarking), • estimating energy use through energy use modeling, • evaluation of potential energy efficiency or efficiency improvements, and • recommendations for energy efficiency with estimates of the costs and savings. 2.1 Building Use The Holy Cross K12 School provides educational services to kindergarten through 12th grade students in Holy Cross, Alaska. 2.2 Building Occupancy and Schedules The building is occupied by 40 students, 4 teachers, and 2 other staff members during the school year, August through May, from approximately 8:00 am to 4:00 pm, weekdays. The gym is used approximately 40 hours a week. 2.3 Building Description The single-story wood-framed school was constructed in 1978 on an all-weather wood frame foundation. An addition in 1987 roughly doubled the square footage of the school. Building Envelope Building Envelope: Walls Wall Type Description Insulation Notes Main Wood-framed with 2x8 studs spaced 16-inches on center. Approximately R-30 fiberglass batt insulation. No as-builts available. Moisture damage prevalent. Crawlspace Wood-framed with 2x6 studs spaced 16-inches on center. Approximately R-30 rigid insulation in stud bays, and R-30 rigid insulation installed horizontally approximately 2 ft below grade. No as-builts available. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 5 Heating and Ventilation Systems Two oil-fired boilers provide heat to the building using baseboards and heating coils to the air handler, cabinet unit heaters, and unit heaters. Three adjustable speed circulation pumps distribute hydronic fluid from the boilers to the building through the building crawlspace. The building temperatures are controlled by nonprogrammable thermostats typically set to 70-72° F. Ventilation Systems An air handling unit (AHU) provides ventilation and some heating to the school. However, the AHU is manually shut down so mechanical ventilation is currently limited to exhaust fans. Building Envelope: Floors Floor Type Description Insulation Notes Crawlspace Bare earth. None Install 6-mil polyethylene vapor barrier. Building Envelope: Roof Roof Type Description Insulation Notes School Wood framed with deep trusses. Approximately R-85 fiberglass loose fill plus R-2 rigid insulation on exterior. No as-builts available. Moisture damage severe in places, recurring leaks and dry rot found. Building Envelope: Doors and Windows Door and Window Type Description Estimated R-Value Notes All Doors Metal ( ½ -lite or no-lite) insulated exterior doors with no thermal break. R-2.5 to R-3.4 None. Windows Double-pane wood/vinyl windows. Some single pane windows. R-1.1 to R-2.0 None. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 6 Air Conditioning System Economizer cooling is possible with the existing system. Energy Management No energy management system is installed. Lighting Systems High-use areas such as classrooms are lit by ceiling mounted fluorescent fixtures with T8 lamps and efficient electronic ballasts controlled by occupancy sensors. The gym is lit by high-bay fluorescent fixtures with T5 high output lamps, and individual occupancy sensors. Exterior lighting fixtures are wall packs and ceiling packs with metal halide 70W to 100W lamps. Utility areas are illuminated by ceiling mounted fluorescent fixtures with T12 lamps (1.5 inch diameter tubes). The crawlspace and a few other low-use areas are lit with incandescent 75W and 100W lamps. Domestic Hot Water An oil-fired hot water heater provides Domestic Hot Water (DHW) to the school. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 7 3.0 BENCHMARKING 2010 UTILITY DATA Benchmarking building energy use consists of obtaining and then analyzing two years of energy bills. The original utility bills are necessary to determine the raw usage, and charges as well as to evaluate the utility’s rate structure. The metered usage of electrical and natural gas consumption is measured monthly, but heating oil, propane, wood, and other energy sources are normally billed upon delivery and provide similar information. During benchmarking, information is compiled in a way that standardizes the units of energy and creates energy use and billing rate information statistics for the building on a square foot basis. The objectives of benchmarking are: • to understand patterns of use, • to understand building operational characteristics, • for comparison with other similar facilities in Alaska and across the country, and • to offer insight in to potential energy savings. The results of the benchmarking, including the energy use statistics and comparisons to other areas, are discussed in the following sections. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 8 3.1 Total Energy Use and Cost of 2010 The energy use profiles below show the energy and cost breakdowns for the Holy Cross K12 School. The total annual energy use was 1,648 mmBTUs and the cost for the school was $72,276 per year. Since the existing 2010 fuel data was not reliable and new boiler metering had been installed in mid-2011, hour-meter data was collected by the NORTECH field team in order to estimate oil consumption. The additional fuel consumed by the separate, currently unmeasured oil-fired hot water heater was estimated using the AkWarm model. Oil cost was based on the cost per gallon of #1 fuel oil listed in the most recent invoice. These charts show the portion of use for a fuel type and the portion of its cost. The above charts indicate that the highest portion of energy use is for oil and the highest portion of cost is for electric. Fuel oil consumption correlates directly to space heating and domestic hot water while electrical use can correlate to lighting systems, plug loads, and HVAC equipment. The energy type with the highest cost often provides the most opportunity for savings. Electric 270 17% Oil 1,357 82% Propane 22 1% Energy Use Total (mmBTU) Electric $40,809 58% Oil $26,917 38% Propane $2,490 4% Energy Cost Total ($) Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 9 3.2 Energy Utilization Index of 2010 The primary benchmarking statistic is the Energy Utilization Index (EUI). The EUI is calculated from the utility bills and provides a snapshot of the quantity of energy actually used by the building on a square foot and annual basis. The calculation converts the total energy use for the year from all sources in the building, such as heating fuel and electrical usage, into British Thermal Units (BTUs). This total annual usage is then divided by the number of square feet of the building. The EUI units are BTUs per square foot per year. The benchmark analysis found that the Holy Cross K12 School has an EUI of 84,000 BTUs per square foot per year. The EUI is useful in comparing this building’s energy use to that of other similar buildings in Alaska and in the Continental United States. The EUI can be compared to average energy use in 2003 found in a study by the U.S. Energy Information Administration of commercial buildings (abbreviated CBECS, 2006). That report found an overall average energy use of about 90,000 BTUs per square foot per year while studying about 6,000 commercial buildings of all sizes, types, and uses that were located all over the Continental U.S. (see Table C3 in Appendix I). In a recent and unpublished state-wide benchmarking study sponsored by the Alaska Housing Finance Corporation, schools in Fairbanks averaged 62,000 BTUs per square foot and schools in Anchorage averaged 123,000 BTUs per square foot annual energy use. The chart below shows the Holy Cross K12 School relative to these values. These findings are discussed further in Appendix H. 84, 000 62,000 123,000 0 20000 40000 60000 80000 100000 120000 140000 Btu/ Sq. Ft Annual Energy Use Index (Total Energy/ SF) Holy Cross K12 School Fairbanks Schools Anchorage Schools Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 10 3.3 Cost Utilization Index of 2010 Another useful benchmarking statistic is the Cost Utilization Index (CUI), which is the cost for energy used in the building on a square foot basis per year. The CUI is calculated from the cost for utilities for a year period. The CUI permits comparison of buildings on total energy cost even though they may be located in areas with differing energy costs and differing heating and/or cooling climates. The cost of energy, including heating oil, natural gas, and electricity, can vary greatly over time and geographic location and can be higher in Alaska than other parts of the country. The CUI for the Holy Cross K12 School is about $3.79 per square foot. This is based on utility costs from 2010 and the following rates: Electricity at $ 0.53 / kWh ($ 15.53 / Therm) # 1 Fuel Oil at $ 2.99 / gallon ($ 2.15 / Therm) Propane at $ 10.56 / gallon ($ 11.53 / Therm) The Department of Energy Administration study, mentioned in the previous section (CBECS, 2006) found an average cost of $2.52 per square foot in 2003 for 4,400 buildings in the Continental U.S (Tables C4 and C13 of CBDES, 2006). Schools in Fairbanks have an average cost for energy of $2.42 per square foot while Anchorage schools average $2.11 per square foot. The chart below shows the Holy Cross K12 School relative to these values. More details are included in Appendix H. $3.79 $2.42 $2.11 $0.00 $0.50 $1.00 $1.50 $2.00 $2.50 $3.00 $3.50 $4.00 $/Sq. Ft Annual Energy Cost Index (Total Cost/ SF) Holy Cross K12 School Fairbanks Schools Anchorage Schools Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 11 3.4 Seasonal Energy Use Patterns Energy consumption is often highly correlated with seasonal climate and usage variations. The graphs below show the electric and fuel consumption of this building over the course of two years. The lowest monthly use is called the baseline use. The electric baseline often reflects year round lighting consumption while the heating fuel baseline often reflects year round hot water usage. The clear relation of increased energy usage during periods of cold weather can be seen in the months with higher usage. Fuel oil consumption is based on boiler run time hours recorded by the NORTECH field team and extrapolated using daily local Heating Degree Days (HDD). Only one propane delivery is recorded from January 2009 to January 2012. 0 2,000 4,000 6,000 8,000 10,000 Jan-09Mar-09May-09Jul-09Sep-09Nov-09Jan-10Mar-10May-10Jul-10Sep-10Nov-10Jan-11Mar-11May-11Jul-11Sep-11Nov-11Jan-12KWH Electrical Consumption 0 200 400 600 800 1,000 1,200 1,400 1,600 Jan-09Mar-09May-09Jul-09Sep-09Nov-09Jan-10Mar-10May-10Jul-10Sep-10Nov-10Jan-11Mar-11May-11Jul-11Sep-11Nov-11Jan-12Gallons Fuel Oil Consumption 0 100 200 300 400 500 Jan-09Mar-09May-09Jul-09Sep-09Nov-09Jan-10Mar-10May-10Jul-10Sep-10Nov-10Jan-11Mar-11May-11Jul-11Sep-11Nov-11Jan-12Gallons Propane Deliveries Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 12 3.5 Future Energy Monitoring Energy accounting is the process of tracking energy consumption and costs. It is important for the building owner or manager to monitor and record both the energy usage and cost each month. Comparing trends over time can assist in pinpointing major sources of energy usage and aid in finding effective energy efficiency measures. There are two basic methods of energy accounting: manual and automatic. Manual tracking of energy usage may already be performed by an administrative assistant, however if the records are not scrutinized for energy use, then the data is merely a financial accounting. Digital energy tracking systems can be installed. They display and record real-time energy usage and accumulated energy use and cost. There are several types which have all of the information accessible via Ethernet browser. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 13 4.0 MODELING ENERGY CONSUMPTION After benchmarking of a building is complete and the site visit has identified the specific systems in the building, a number of different methods are available for quantifying the overall energy consumption and to model the energy use. These range from relatively simple spreadsheets to commercially available modeling software capable of handling complex building systems. NORTECH has used several of these programs and uses the worksheets and software that best matches the complexity of the building and specific energy use that is being evaluated. Modeling of an energy efficiency measure (EEM) requires an estimate of the current energy used by the specific feature, the estimated energy use of the proposed EEM and its installed cost. EEMs can range from a single simple upgrade, such as light bulb type or type of motor, to reprogramming of the controls on more complex systems. While the need for a major retrofit can typically be identified by an energy audit, the specific system upgrades often require collecting additional data and engineering and design efforts that are beyond the scope of the Level II energy audit. Based on the field inspection results and discussions with the building owners/operators, auditors developed potential EEMs for the facility. Common EEMs that could apply to almost every older building include: • Reduce the envelope heat losses through: o increased building insulation, and o better windows and doors • Reduce temperature difference between inside and outside using setback thermostats • Upgrade inefficient: o lights, o motors, o refrigeration units, and o other appliances • Reduce running time of lights/appliances through: o motion sensors, o on/off timers, o light sensors, and o other automatic/programmable systems The objective of the following sections is to describe how the overall energy use of the building was modeled and the potential for energy savings. The specific EEMs that provide these overall energy savings are detailed in Appendix A of this report. While the energy savings of an EEM is unlikely to change significantly over time, the cost savings of an EEM is highly dependent on the current energy price and can vary significantly over time. An EEM that is not currently recommended based on price may be more attractive at a later date or with higher energy prices. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 14 4.1 Understanding How AkWarm Models Energy Consumption NORTECH used the AkWarm model for evaluating the overall energy consumption at the Holy Cross K12 School. The AkWarm program was developed by the Alaska Housing Finance Corporation (AHFC) to model residential energy use. The original AkWarm is the modeling engine behind the successful residential energy upgrade program that AHFC has operated for a number of years. In the past few years, AHFC has developed a version of this model for commercial buildings. Energy use in buildings is modeled by calculating energy losses and consumption, such as: • Heat lost through the building envelope components, including windows, doors, walls, ceilings, crawlspaces, and foundations. These heat losses are computed for each component based on the area, heat resistance (R-value), and the difference between the inside temperature and the outside temperature. AkWarm has a library of temperature profiles for villages and cities in Alaska. • Window orientation, such as the fact that south facing windows can add heat in the winter but north-facing windows do not. • Inefficiencies of the heating system, including the imperfect conversion of fuel oil or natural gas due to heat loss in exhaust gases, incomplete combustion, excess air, etc. Some electricity is also consumed in moving the heat around a building through pumping. • Inefficiencies of the cooling system, if one exists, due to various imperfections in a mechanical system and the required energy to move the heat around. • Lighting requirements and inefficiencies in the conversion of electricity to light; ultimately all of the power used for lighting is converted to heat. While the heat may be useful in the winter, it often isn’t useful in the summer when cooling may be required to remove the excess heat. Lights are modeled by wattage and operational hours. • Use and inefficiencies in refrigeration, compressor cooling, and heat pumps. Some units are more efficient than others. Electricity is required to move the heat from inside a compartment to outside it. Again, this is a function of the R-Value and the temperature difference between the inside and outside of the unit. • Plug loads such as computers, printers, mini-fridges, microwaves, portable heaters, monitors, etc. These can be a significant part of the overall electricity consumption of the building, as well as contributing to heat production. • The schedule of operation for lights, plug loads, motors, etc is a critical component of how much energy is used. AkWarm adds up these heat losses and the internal heat gains based on individual unit usage schedules. These estimated heat and electrical usages are compared to actual use on both a yearly and seasonal basis. If the AkWarm model is within 5 % to 10% of the most recent 12 months usage identified during benchmarking, the model is considered accurate enough to make predictions of energy savings for possible EEMs. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 15 4.2 AkWarm Calculated Savings for the Holy Cross K12 School Based on the field inspection results and discussions with the building owners/operators, auditors developed potential EEMs for the facility. These EEMs are then entered into AkWarm to determine if the EEM saves energy and is cost effective (i.e. will pay for itself). AkWarm calculates the energy and money saved by each EEM and calculates the length of time for the savings in reduced energy consumption to pay for the installation of the EEM. AkWarm makes recommendations based on the Savings/Investment Ratio (SIR), which is defined as ratio of the savings generated over the life of the EEM divided by the installed cost. Higher SIR values are better and any SIR above one is considered acceptable. If the SIR of an EEM is below one, the energy savings will not pay for the cost of the EEM and the EEM is not recommended. Preferred EEMs are listed by AkWarm in order of the highest SIR. A summary of the savings from the recommended EEMs are listed in this table. Description Space Heating Water Heating Lighting Refrigeration Other Electrical Cooking Ventilation Fans Total Existing Building $58,062 $2,060 $18,040 $4,399 $2,653 $1,665 $38 $86,918 With All Proposed Retrofits $45,283 $2,060 $16,895 $3,127 $2,369 $1,665 $38 $71,438 Savings $12,779 $0 $1,145 $1,272 $284 $0 $0 $15,480 Savings in these categories represent the overall savings for the building, and reflect any added cost that might occur because of a retrofit. For example, installing more efficient lights will increase the heating load and creating or lowering an unoccupied setback temperature will increase hot water heat losses and cost. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 16 4.3 Additional Modeling Methods The AkWarm program effectively models wood-framed and other buildings with standard heating systems and relatively simple HVAC systems. AkWarm models of more complicated mechanical systems are sometimes poor due to a number of simplifying assumptions and limited input of some variables. Furthermore, AKWarm is unable to model complex HVAC systems such as variable frequency motors, variable air volume (VAV) systems, those with significant digital or pneumatic controls or significant heat recovery capacity. In addition, some other building methods and occupancies are outside AkWarm capabilities. This report section is included in order to identify benefits from modifications to those more complex systems or changes in occupant behavior that cannot be addressed in AkWarm. The AkWarm building model which incorporated estimated hot water consumption predicted larger quantities of oil consumption than the 2010 data, but less than both the 2011 data and the extrapolated consumption based on boiler run-time data collected by the energy audit field team. That is to say, that the benchmarking fuel consumption data did not allow AkWarm to be calibrated within NORTECH standards. Therefore, energy savings and cost savings predicted by AkWarm have a higher than standard range of error. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 17 5.0 BUILDING OPERATION AND MAINTENANCE (O & M) 5.1 Operations and Maintenance A well-implemented operation and maintenance (O & M) plan is often the driving force behind energy savings. Such a plan includes preserving institutional knowledge, directing preventative maintenance, and scheduling regular inspections of each piece of HVAC equipment within the building. Such a plan includes a regularly scheduled inspection of each piece of HVAC equipment within the building. Routine maintenance includes the timely replacement of filters, belts and pulleys, the proper greasing of bearings and other details such as topping off the glycol tanks. Additional benefits to a maintenance plan are decreased down time for malfunctioning equipment, early indications of problems, prevention of exacerbated maintenance issues, and early detection of overloading/overheating issues. A good maintenance person knows the building’s equipment well enough to spot and repair minor malfunctions before they become major retrofits. Operations and Maintenance staff implementing a properly designed O & M plan will: • Track and document o Renovations and repairs, o Utility bills and fuel consumption, and o System performance. • Keep available for reference o A current Building Operating Plan including an inventory of installed systems, o The most recent available as-built drawings, o Reference manuals for all installed parts and systems, and o An up-to-date inventory of on-hand replacement parts. • Provide training and continuing education for maintenance personnel. • Plan for commissioning and re-commissioning at appropriate intervals. • 5.2 Commissioning Commissioning of a building is the verification that the HVAC systems perform within the design or usage ranges of the Building Operating Plan. This process ideally, though seldom, occurs as the last phase in construction. HVAC system operation parameters degrade from ideal over time due to incorrect maintenance, improper replacement pumps, changes in facility tenants or usage, changes in schedules, and changes in energy costs or loads. Ideally, re-commissioning of a building should occur every five to ten years. This ensures that the HVAC system meets the potentially variable use with the most efficient means. 5.3 Building Specific Recommendations The current lack of ventilation capacity would generally be considered unacceptable by mechanical engineers and code officials, but the state of disrepair of the existing air handler prevents proper operation except for manually-operated economizer cooling during spring. Repair or replacement of the controls and AHU and recommisioning of the ventilation system should be performed. As a part of the commissioning, a Level III audit to establish minimum necessary ventilation levels to comply with mechanical code using demand-controlled Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 18 ventilation and a variable-position outside air damper can be performed to reduce the energy costs of the necessary ventilation. Roof leaks have resulted in rot developing in various areas of the wood-framed walls, roof and supports and water marks on interior walls such as in the gym and room 115. Snow pressure has cracked several windows. The building should be repaired, or replaced with a school sized for the predicted enrollment and designed for the climate. The existing exterior lights are reportedly on only a few hours per night, but if the lights are actually used more often, significant savings will be achieved by replacing the exterior lights with LED wall packs with photocell and occupancy sensor controls. Schools with comparable utility costs had projected savings of approximately $300.00 per light per year. A six mil polyethylene vapor barrier should be installed over the soil in the crawlspace to reduce moisture intrusion into the building. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 19 APPENDICES Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 20 Appendix A Recommended Energy Efficiency Measures A number of Energy Efficiency Measures (EEMs) are available to reduce the energy use and overall operating cost for the facility. The EEMs listed below are those recommended by AkWarm based on the calculated savings/investment ration (SIR) as described in Appendix E. AkWarm also provides a breakeven cost, which is the maximum initial cost of the EEM that will still return a SIR of one or greater. This section describes each recommended EEM and identifies the potential energy savings and installation costs. This also details the calculation of breakeven costs, simple payback, and the SIR for each recommendation. The recommended EEMs are grouped together generally by the overall end use that will be impacted. A.1 Temperature Control Fifteen programmable thermostats should be installed and programmed for a night-time and unoccupied setback of 60°F in classrooms, hallways, locker rooms, and the gym. Programmable thermostats allow for automatic temperature setback, which reduce usage more reliably than manual setbacks. Instituting a night-time and unoccupied temperature set back will decrease the amount of energy required to heat the building. Rank Building Space Recommendation 1 School Install 15 programmable thermostats, and implement a heating temperature night time and unoccupied setback to 60°F for the building. Installation Cost $4,500 Estimated Life of Measure (yr) 15 Energy Savings (/yr) $8,265 Breakeven Cost $111,842 Savings-to-Investment Ratio 25 Simple Payback (yr) 1 A.2 Electrical Loads A.2.1 Lighting The electricity used by lighting eventually ends up as heat in the building. In areas where electricity is more expensive than other forms of energy, or in areas where the summer temperatures require cooling; this additional heat can be both wasteful and costly. Converting to more efficient lighting reduces cooling loads in the summer and allows the user to control heat input in the winter. The conversion from T12 (one and a half inch fluorescent lamps) to T8 (one inch), T5 (5/8 inch), Compact Fluorescent Lights (CFL), or LED lamps provides a significant increase in efficiency. LED lamps can be directly placed in existing fixtures. The LED lamp bypasses the ballast altogether, which removes the often irritating, “buzzing” noise that magnetic ballasts tend to make. Most lighting has already been retrofitted to fluorescent fixtures with T8 lamps and electronic ballasts; and existing fluorescent fixtures with T12 lamps are employing 32W energy saver lamps, already have occupancy sensors, and are used less frequently in general, which reduces potential savings. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 21 However, the peripheral lobby lights increase the lighting levels only slightly and can be removed for some energy savings, since primary lighting is provided by fluorescent fixtures using T12 and T8 lamps. Additional savings are achieved by replacing incandescent bulbs with 13W spiral CFLs. A.2.2 Other Electrical Loads Replacing the existing glass-front commercial coolers with more efficient full-size Tier III Energy Star refrigerators will result in significant refrigeration energy savings. In order to achieve further energy savings, institute summer shutdown of refrigerators and consolidate frozen items in order to shut down unused freezers; and remove humidifiers, space heaters, and mini-refrigerators from classrooms. A.3 Building Envelope: Recommendations for change A.3.1 Exterior Walls No EEMS are recommended in this area because construction cost makes retrofits uneconomical. Rank Location Existing Condition Recommendation 2 Lobby Lighting 1 FLUOR [Unknown Lamp] with Manual Switching Replace with FLUOR T12 4' F40T12 40W Standard Installation Cost $500 Estimated Life of Measure (yr) 15 Energy Savings (/yr) $71 Breakeven Cost $7,843 Savings-to-Investment Ratio 16 Simple Payback (yr) 1 Rank Location Existing Condition Recommendation 2 Incandescent (miscel) 10 INCAN A Lamp, Std 75W with Manual Switching Replace with 10 FLUOR CFL, Spiral 13 W Installation Cost $100 Estimated Life of Measure (yr) 7 Energy Savings (/yr) $6,144 Breakeven Cost $442 Savings-to-Investment Ratio 4.4 Simple Payback (yr) 9 Rank Location Existing Condition Recommendation 2 School Space heaters, humidifier, mini-refrigerator and 2 ½ full glass-front commercial coolers. Also four chest freezers, ¾ full. Remove space heaters, humidifiers and mini-fridges from classrooms. Replace glass-front refrigerators with Energy Star full-size refrigerators. . Installation Cost $1,096 Estimated Life of Measure (yr) 7 Energy Savings (/yr) $2,700 Breakeven Cost $6,612 Savings-to-Investment Ratio 2.7 Simple Payback (yr) 2.5 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 22 A.3.2 Foundation and/or Crawlspace Installing R-30 encapsulated fiberglass batt insulation in a four foot perimeter of the crawlspace floor will reduce heat loss through the crawlspace floor. A.3.3 Roofing and Ceiling No EEMS are recommended in this area because construction cost makes retrofits uneconomical. A.3.4 Windows No EEMS are recommended in this area because construction cost makes retrofits uneconomical. A.3.5 Doors No EEMS are recommended in this area because construction cost makes retrofits uneconomical. A.4 Building Heating System / Air Conditioning A.4.1 Heating and Heat Distribution Replacing the primary heating circulation pumps with appropriately-sized Grundfos Magna or Alpha circulation pumps or equivalent, will result in savings of at least 50% due to the improved motor design. Fuel consumption logs should be kept to determine if additional savings could be achieved by replacing the existing hot water heater with a typically more efficient indirect hot water heater such as the Amtrol Boilermate, in which the hot water is heated by coils off the boilers. Oil consumption of the oil-fired hot water heater is not currently monitored. Rank Location Existing Condition Recommendation 8 On- or Below-Grade Floor, Perimeter: Crawlspace and Basement Insulation for 0' to 2' Perimeter: XPS (Blue/Pink Foam), 2 inches Insulation for 2' to 4' Perimeter: XPS (Blue/Pink Foam), 2 inches Modeled R-Value: 27.4 Install R-30 Fiberglass Batts on the Perimeter 4 feet of the Crawl Space Floor. Installation Cost $11,155 Estimated Life of Measure (yr) 30 Energy Savings (/yr) $837 Breakeven Cost $19,765 Savings-to-Investment Ratio 1.8 Simple Payback (yr) 13 Rank Location Recommendation 4 Boiler Room Replace primary heating circulation pumps with appropriately-sized Grundfos Magna or Alpha circulation pumps, or equivalent, which will result in savings of at least 50% due to improved motor design. Installation Cost $15,000 Estimated Life of Measure (yr) 10 Energy Savings (/yr) $4,488 Breakeven Cost $35,626 Savings-to-Investment Ratio 2.4 Simple Payback (yr) 3 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 23 A.4.2 Air Conditioning No EEMS are recommended in this area because there is no existing air conditioning system. A.4.3 Ventilation No EEMs are currently recommended in this area because of the difficulty of quantifying the amount of ventilation air and the savings. However, a Level III audit during recommissioning of the ventilation system should be performed to keep ventilation costs to a minimum. A.4.4 Air Changes and Air Tightening No EEMs are recommended in this area because of the difficulty of quantifying the amount of leaking air and the savings. However, by using a blower door to depressurize the building and an infra-red camera, the location of significant air leaks can be determined so they can be repaired. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 24 Appendix B Energy Efficiency Measures that are NOT Recommended As indicated in other sections of the report, a number of potential EEMs were identified that were determined to be NOT cost effective by the AkWarm model. These EEMs are not currently recommended on the basis of energy savings alone because each may only save a small amount of energy, have a high capital cost, or be expensive to install. While each of these EEMs is not cost effective at this time, future changes in building use such as longer operating hours, higher energy prices, new fixtures or hardware on the market, and decreases in installation effort may make any of these EEMs cost effective in the future. These potential EEMs should be reviewed periodically to identify any changes to these factors that would warrant re-evaluation. Although these upgrades are not currently cost effective on an energy cost basis, the fixtures, hardware, controls, or operational changes described in these EEMs should be considered when replacing an existing fixture or unit for other reasons. For example, replacing an existing window with a triple-pane window may not be cost effective based only on energy use, but if a window is going to be replaced for some other reason, then the basis for a decision is only the incremental cost of upgrading from a less efficient replacement window to a more efficient replacement window. That incremental cost difference will have a significantly shorter payback, especially since the installation costs are likely to be the same for both units. The following measures were not found to be cost-effective: Rank Feature/Location Improvement Description Annual Energy Savings Installed Cost Savings to Investment Ratio, SIR Simple Payback (Years) 12 Window/Skylight: single pane Replace existing window with triple pane, 2 low-E, argon window. $1,259 $26,423 0.83 21 13 Lighting: Lobby Lighting Replace with 8 LED 150W Module StdElectronic $278 $4,800 0.68 17 14 Below- (part or all) Grade Wall: Crawlspace/Basemen t Install R-5 rigid insulation on basement wall $279 $11,105 0.59 40 15 Window/Skylight: double pane Replace existing window with U-0.28 wood window $1,820 $90,854 0.35 50 16 Lighting: T8 school occ 25% Replace with 232 LED (2) 4W Module StdElectronic and Add new Daylight Sensor $3,589 $133,600 0.31 37 17 Lighting: T12 school and occ 50% Replace with 56 FLUOR T12 4' F40T12 40W Standard StdElectronic $717 $31,000 0.27 43 18 Lighting: T12 school and occ 50% Replace with 56 FLUOR T12 4' F40T12 40W Standard StdElectronic $681 $31,000 0.25 46 19 Above-Grade Wall: School Install R-5 rigid foam board to exterior and cover with T1-11 siding or equivalent. $1,131 $140,701 0.19 120 20 On- or Below-Grade Floor, Center: Crawlspace/ Basement Install R-5 insulation on center of basement floor $670 $94,871 0.17 140 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 25 The following measures were not found to be cost-effective: Rank Feature/Location Improvement Description Annual Energy Savings Installed Cost Savings to Investment Ratio, SIR Simple Payback (Years) 21 Cathedral Ceiling: School Install R-5 rigid board insulation. No cost included for covering insulation. $630 $90,073 0.17 140 22 Other Electrical: varies Replace with 30 Mac Mini $327 $45,000 0.04 140 23 Lighting: T8 1/day man Replace with 8 LED (2) 4W Module StdElectronic $12 $4,490 0.03 380 Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 26 Appendix C Significant Equipment List HVAC Equipment Equipment Manufacturer Model No. Notes (2) Boilers Burnham PF 504 402 kBTUs (3.0 gph nozzle). (3) Primary Circulation Pumps Grundfos UPC 65-160 -- DHW Circulation Pump Grundfos UPS 15-58 -- (4) Unit Heaters and Cabinet Heaters varies varies -- (1) Air Handling Unit Trane Climate Changer (1) supply fan, not in operation except for manual economizer cooling. (5) Exhaust Fans varies varies -- Oil-fired Hot Water Heater Bock 51E -- Lighting Location Lighting Type Lamp Type Quantity KWH/YR Cost per Year Building Wide Fluorescent T8 480 20,800 $ 11,024 Building Wide Fluorescent T12 112 4,250 2,252 Gym Fluorescent T5 72 6,800 3,604 Lobby Fluorescent Varies 8 2,000 1,060 Exterior Metal Halide 100W 10 600 318 Energy Consumption calculated by AkWarm based on wattage, schedule, and an electricity rate of $0.53/kWh Plug Loads Equipment Location Manufacturer KWH/YR Cost per Year Refrigerators Kitchen, various Varies 8,300 $ 4,399 Office Equipment School Varies 2,500 1,325 Microwave School Varies 1,400 742 Space Heater and Humidifier Classrooms Varies 480 254 Television Classrooms n/a 400 212 Coffeemaker Building-wide Varies 200 106 Energy Consumption calculated by AkWarm based on wattage, schedule, and an electricity rate of $0.53/kWh Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 27 Appendix D Local Utility Rate Structure The information in this section was provided directly from the local utility or gathered from the local utility’s publicly available information at the time of the audit. All language used in this section was provided by the local utility and believed to be current at the time of the audit. Energy use terms, specific fees, and other specific information are subject to change. Updated rate structure information should be gathered from the utility during future discussion of rates, rate structures and utility pricing agreements. Blackwell School is classified as a Large Power GS-2 customer. Alaska Village Electric Cooperative, Inc. (AVEC) 4831 Eagle St. Anchorage, Alaska, 99503 (907) 561-1818 Customer Charge A flat fee that covers costs for meter reading, billing and customer service. Utility Charge (kWh charge) This charge is multiplied by the number of kilowatt-hours (kWh) used in a monthly billing period. It covers the costs to maintain power plants and substations, interest on loans as well as wires, power poles and transformers. Regulatory Charge This charge of .000492 per kWh is set by the Regulatory Commission of Alaska (RCA). Since November 1, 1992, the Regulatory Commission of Alaska has been funded by a Regulatory Charge to the utilities it regulates rather than through the State general fund. The charge, labeled "Regulatory Cost Charge." on your bill, is set by the RCA, and applies to all retail kilowatt-hours sold by regulated electric utilities in Alaska. Demand Charge This charge is based upon high KW demand during the month or 85% of the highest KW demand (rachet) during the past 12 months, whichever is higher. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 28 Appendix E Analysis Methodology Data collected was processed using AkWarm energy use software to estimate current energy consumption by end usage and calculate energy savings for each of the proposed energy efficiency measures (EEMs). In addition, separate analysis may have been conducted to evaluate EEMs that AkWarm cannot effectively model to evaluate potential reductions in annual energy consumption. Analyses were conducted under the direct supervision of a Certified Energy Auditor, Certified Energy Manager, or a Professional Engineer. EEMs are evaluated based on building use, maintenance and processes, local climate conditions, building construction type, function, operational schedule and existing conditions. Energy savings are calculated based on industry standard methods and engineering estimations. Each model created in AkWarm is carefully compared to existing utility usage obtained from utility bills. The AkWarm analysis provides a number of tools for assessing the cost effectiveness of various improvement options. The primary assessment value used in this audit report is the Savings/Investment Ratio (SIR). The SIR is a method of cost analysis that compares the total cost savings through reduced energy consumption to the total cost of a project over its assumed lifespan, including both the construction cost and ongoing maintenance and operating costs. Other measurement methods include Simple Payback, which is defined as the length of time it takes for the savings to equal the total installed cost and Breakeven Cost, which is defined as the highest cost that would yield a Savings/Investment Ratio of one. EEMs are recommended by AkWarm in order of cost-effectiveness. AkWarm first calculates individual SIRs for each EEM, and then ranks the EEMs by SIR, with higher SIRs at the top of the list. An individual EEM must have a SIR greater than or equal to one in order to be recommended by AkWarm . Next AkWarm modifies the building model to include the installation of the first EEM and then re-simulates the energy use. Then the remaining EEMs are re- evaluated and ranked again. AkWarm goes through this iterative process until all suggested EEMs have been evaluated. Under this iterative review process, the savings for each recommended EEM is calculated based on the implementation of the other, more cost effective EEMs first. Therefore, the implementation of one EEM affects the savings of other EEMs that are recommended later. The savings from any one individual EEM may be relatively higher if the individual EEM is implemented without the other recommended EEMs. For example, implementing a reduced operating schedule for inefficient lighting may result in relatively higher savings than implementing the same reduced operating schedule for newly installed lighting that is more efficient. If multiple EEMs are recommended, AkWarm calculates a combined savings. Inclusion of recommendations for energy savings outside the capability of AkWarm will impact the actual savings from the AkWarm projections. This will almost certainly result in lower energy savings and monetary savings from AkWarm recommendations. The reality is that only so much energy is consumed in a building. Energy savings from one EEM reduces the amount of energy that can be saved from additional EEMs. For example, installation of a lower wattage light bulb does not save energy or money if the bulb is never turned on because of a schedule or operational change at the facility. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 29 Appendix F Audit Limitations The results of this audit are dependent on the input data provided and can only act as an approximation. In some instances, several EEMs or installation methods may achieve the identified potential savings. Actual savings will depend on the EEM selected, the price of energy, and the final installation and implementation methodology. Competent tradesmen and professional engineers may be required to design, install, or otherwise implement some of the recommended EEMs. This document is an energy use audit report and is not intended as a final design document, operation, and maintenance manual, or to take the place of any document provided by a manufacturer or installer of any device described in this report. Cost savings are calculated based on estimated initial costs for each EEM. Estimated costs include labor and equipment for the full up-front investment required to implement the EEM. The listed installation costs within the report are conceptual budgetary estimates and should not be used as design estimates. The estimated costs are derived from Means Cost Data, industry publications, local contractors and equipment suppliers, and the professional judgment of the CEA writing the report and based on the conditions at the time of the audit. Cost and energy savings are approximations and are not guaranteed. Additional significant energy savings can usually be found with more detailed auditing techniques that include actual measurements of electrical use, temperatures in the building and HVAC ductwork, intake and exhaust temperatures, motor runtime and scheduling, and infrared, air leakage to name just a few. Implementation of these techniques is the difference between a Level III Energy Audit and the Level II Audit that has been conducted. Disclaimer: "This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof." Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 30 Appendix G References Although not all documents listed below are specifically referenced in this report, each contains information and insights considered valuable to most buildings. Alaska Department of Education and Early Development; Education Support Services/Facilities. (1999). Alaska School Facilities Preventative Maintenance Handbook. Juneau, AK: Alaska Department of Education and Early Development. Alaska Housing Finance Corportation. (2010). Retrofit Energy Assessment for Loans. AHFC. ASHRAE. (1997). 1997 ASHRAE Handbook: Fundamentals. Atlanta, GA: ASHRAE. ASHRAE. (2007). ASHRAE Standard 105-2007 Expressing and Comparing Building Energy Performance. Retrieved from ASHRAE: www.ashrae.org ASHRAE. (2007). ASHRAE Standard 90.1-2007 Energy Standards for buildings Except Low- Rise Residential Buildings. Retrieved from ASHRAE: www.ashrae.org ASHRAE. (2010). ASHRAE Standard 62.1-2010 Ventilaton for Acceptable Indoor Air Quality. Retrieved from ASHRAE: www.ashrae.org ASHRAE. (2010). ASHRAE Standard 62.2-2010 Ventilation and Acceptable Indoor Air Quality in Low Rise Residential Buildings. Retrieved from ASHRAE: www.ashrae.org ASHRAE RP-669 and SP-56. (2004). Procedures for Commercial Building Energy Audits. Atlanta, GA: ASHRAE. Coad, W. J. (1982). Energy Engineering and Management for Building Systems. Scarborough, Ontario, Canada: Van Nostrand Reinhold Company. Daley, D. T. (2008). The Little Black Book of Reliability Management. New York, NY: Industrial Press, Inc. Federal Energy Management Program. (2004, March 3). Demand Controlled Ventilation Using CO2 Sensors. Retrieved 2011, from US DOE Energy Efficiency and Renewable Energy: http://www.eere.energy.gov/femp/pdfs/fta_co2.pdf Federal Energy Management Program. (2006, April 26). Low-Energy Building Design Guidelines. Retrieved 2011, from Department of Energy; Federal Energy Management Program: http://www.eren.doe.gov/femp/ Institute, E. a. (2004). Variable Speed Pumping: A Guide to Successful Applications. Oxford, UK: Elsevier Advanced Technology. International Code Council. (2009). International Energy Conservation Code. Country Club Hills, IL: International Code Council, Inc. Leach, M., Lobato, C., Hirsch, A., Pless, S., & Torcellini, P. (2010, September). Technical Support Document: Strategies for 50% Energy Savings in Large Office Buildings. Retrieved 2011, from National Renewable Energy Laboratory: http://www.nrel.gov/docs/fy10osti/49213.pdf Thumann, P.E., C.E.M., A., Younger, C.E.M., W. J., & Niehus, P.E., C.E.M., T. (2010). Handbook of Energy Audits Eighth Edition. Lilburn, GA: The Fairmont Press, Inc. U.S. Energy Information Administration. (2006). Commercial Building Energy Consumption Survey (CBECS). Retrieved 2011, from Energy Information Administration: http://www.eia.gov/emeu/cbecs/ Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 31 Appendix H Typical Energy Use and Cost – Fairbanks and Anchorage This report provides data on typical energy costs and use on selected building in Fairbanks and Anchorage, Alaska for comparative purposes only. The values provided by the US Energy Information Administration CBECS study included a broader range of building types for the Continental U.S. are not necessarily good comparatives for buildings and conditions in Alaska. An assortment of values from CBECS may be found in Appendix I. The Alaska data described in this report came from a benchmarking study NORTECH and other Technical Services Providers (TSPs) completed on publicly owned buildings in Alaska under contract with AHFC. This study acquired actual utility data for municipal buildings and schools in Alaska for the two recent full years. The utility data included costs and quantities including fuel oil, electricity, propane, wood, steam, and all other energy source usage. This resulted in a database of approximately 900 buildings. During the course of the benchmarking study, the comparisons made to the CBECS data appeared to be inappropriate for various reasons. Therefore, this energy use audit report references the average energy use and energy cost of Anchorage and Fairbanks buildings as described below. The Alaska benchmarking data was evaluated in order to find valid comparison data. Buildings with major energy use information missing were eliminated from the data pool. After detailed scrutiny of the data, the most complete information was provided to NORTECH by the Fairbanks North Star Borough School District (FNSBSD) and the Anchorage School District (ASD). The data sets from these two sources included both the actual educational facilities as well as the district administrative buildings and these are grouped together in this report as Fairbanks and Anchorage schools. These two sources of information, being the most complete and reasonable in-state information, have been used to identify an average annual energy usage for Fairbanks and for Anchorage in order to provide a comparison for other facilities in Alaska. Several factors may limit the comparison of a specific facility to these regional indicators. In Fairbanks, the FNSBSD generally uses number two fuel oil for heating needs and electricity is provided by Golden Valley Electric Association (GVEA). GVEA produces electricity from a coal fired generation plant with additional oil generation upon demand. A few of the FNSBSD buildings in this selection utilize district steam and hot water. The FNSBSD has recently (the last ten years) invested significantly in envelope and other efficiency upgrades to reduce their operating costs. Therefore a reader should be aware that this selection of Fairbanks buildings has energy use at or below average for the entire Alaska benchmarking database. Heating in Anchorage is through natural gas from the nearby natural gas fields. Electricity is also provided using natural gas. As the source is nearby and the infrastructure for delivery is in place, energy costs are relatively low in the area. As a result, the ASD buildings have lower energy costs, but higher energy use, than the average for the entire benchmarking database. These special circumstances should be considered when comparing the typical annual energy use for particular buildings. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 32 Appendix I Typical Energy Use and Cost – Continental U.S. Released: Dec 2006 Next CBECS will be conducted in 2007 Table C3. Consumption and Gross Energy Intensity for Sum of Major Fuels for Non-Mall Buildings, 2003 All Buildings* Sum of Major Fuel Consumption Number of Buildings (thousand) Floor space (million square feet) Floor space per Building (thousand square feet) Total (trillion BTU) per Building (million BTU) per Square Foot (thousand BTU) per Worker (million BTU) All Buildings* 4,645 64,783 13.9 5,820 1,253 89.8 79.9 Building Floor space (Square Feet) 1,001 to 5,000 2,552 6,789 2.7 672 263 98.9 67.6 5,001 to 10,000 889 6,585 7.4 516 580 78.3 68.7 10,001 to 25,000 738 11,535 15.6 776 1,052 67.3 72.0 25,001 to 50,000 241 8,668 35.9 673 2,790 77.6 75.8 50,001 to 100,000 129 9,057 70.4 759 5,901 83.8 90.0 100,001 to 200,000 65 9,064 138.8 934 14,300 103.0 80.3 200,001 to 500,000 25 7,176 289.0 725 29,189 101.0 105.3 Over 500,000 7 5,908 896.1 766 116,216 129.7 87.6 Principal Building Activity Education 386 9,874 25.6 820 2,125 83.1 65.7 Food Sales 226 1,255 5.6 251 1,110 199.7 175.2 Food Service 297 1,654 5.6 427 1,436 258.3 136.5 Health Care 129 3,163 24.6 594 4,612 187.7 94.0 Inpatient 8 1,905 241.4 475 60,152 249.2 127.7 Outpatient 121 1,258 10.4 119 985 94.6 45.8 Lodging 142 5,096 35.8 510 3,578 100.0 207.5 Retail (Other Than Mall) 443 4,317 9.7 319 720 73.9 92.1 Office 824 12,208 14.8 1,134 1,376 92.9 40.3 Public Assembly 277 3,939 14.2 370 1,338 93.9 154.5 Public Order and Safety 71 1,090 15.5 126 1,791 115.8 93.7 Religious Worship 370 3,754 10.1 163 440 43.5 95.6 Service 622 4,050 6.5 312 501 77.0 85.0 Warehouse and Storage 597 10,078 16.9 456 764 45.2 104.3 Other 79 1,738 21.9 286 3,600 164.4 157.1 Vacant 182 2,567 14.1 54 294 20.9 832.1 This report references the Commercial Buildings Energy Consumption Survey (CBECS), published by the U.S. Energy Information Administration in 2006. Initially this report was expected to compare the annual energy consumption of the building to average national energy usage as documented below. However, a direct comparison between one specific building and the groups of buildings outlined below yielded confusing results. Instead, this report uses a comparative analysis on Fairbanks and Anchorage data as described in Appendix F. An abbreviated excerpt from CBECS on commercial buildings in the Continental U.S. is below. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 33 Appendix J List of Conversion Factors and Energy Units 1 British Thermal Unit is the energy required to raise one pound of water one degree F° 1 Watt is approximately 3.412 BTU/hr. 1 horsepower is approximately 2,544 BTU/hr. 1 horsepower is approximately 746 Watts 1 "ton of cooling” is approximately 12,000 BTU/hr., the amount of power required to melt one short ton of ice in 24 hours 1 Therm = 100,000 BTU 1 KBTU = 1,000 BTU 1 KWH = 3413 BTU 1 KW = 3413 BTU/Hr. 1 Boiler HP = 33,400 BTU/Hr. 1 Pound Steam = approximately 1000 BTU 1 CCF of natural gas = approximately 1 Therm 1 inch H2O = 250 Pascal (Pa) = 0.443 pounds/square inch (psi) 1 atmosphere (atm) = 10,1000 Pascal (Pa) BTU British Thermal Unit CCF 100 Cubic Feet CFM Cubic Feet per Minute GPM Gallons per minute HP Horsepower Hz Hertz kg Kilogram (1,000 grams) kV Kilovolt (1,000 volts) kVA Kilovolt-Amp kVAR Kilovolt-Amp Reactive KW Kilowatt (1,000 watts) KWH Kilowatt Hour V Volt W Watt Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 34 Appendix K List of Acronyms, Abbreviations, and Definitions ACH Air Changes per Hour AFUE Annual Fuel Utilization Efficiency Air Economizer A duct, damper, and automatic control system that allows a cooling system to supply outside air to reduce or eliminate the need for mechanical cooling. Ambient Temperature Average temperature of the surrounding air Ballast A device used with an electric discharge lamp to cause the lamp to start and operate under the proper circuit conditions of voltage, current, electrode heat, etc. CO2 Carbon Dioxide CUI Cost Utilization Index CDD Cooling Degree Days DDC Direct Digital Control EEM Energy Efficiency Measure EER Energy Efficient Ratio EUI Energy Utilization Index FLUOR Fluorescent Grade The finished ground level adjoining a building at the exterior walls HDD Heating Degree Days HVAC Heating, Ventilation, and Air-Conditioning INCAN Incandescent NPV Net Present Value R-value Thermal resistance measured in BTU/Hr-SF-̊F (Higher value means better insulation) SCFM Standard Cubic Feet per Minute Savings to Investment Ratio (SIR) Savings over the life of the EEM divided by Investment capital cost. Savings includes the total discounted dollar savings considered over the life of the improvement. Investment in the SIR calculation includes the labor and materials required to install the measure. Set Point Target temperature that a control system operates the heating and cooling system Simple payback A cost analysis method whereby the investment cost of an EEM is divided by the first year’s savings of the EEM to give the number of years required to recover the cost of the investment. Energy Audit – Final Report Holy Cross K12 School Holy Cross, Alaska F:\00-Jobs\2011\2602 F - AHFC Grade Audits\50-300 Doyon Other Region\50-395 Iditarod Area SD\50-396 Holy Cross School\Reports\Final\2012.07.10 AHFC Final Report HCR-K12 School.Docx 35 Appendix L Building Floor Plan