FY14 SRP Business Solutions Retrocommissioning Plan

Transcription

1 FY14 SRP Business Solutions Poston Butte High School Located at: N Gantzel Rd San Tan Valley, Arizona Presented to: Florence Unified School District Project # RCS02_ March 10 th, 2014

2 Disclaimer The intent of this is to provide a preliminary estimate of the potential energy and demand savings available at the project site and identify a tentative plan for completing the detailed retrocommissioning investigative activities. While the preliminary findings in this report have been reviewed for technical accuracy and are believed to be reasonably accurate, the actual results may vary. SRP and Nexant are not liable if estimated savings or economics are not realized. All savings and cost estimates in the report are for informational purposes, and are not to be construed as a design document or as guarantees. Florence Unified School District shall independently evaluate any advice or suggestions provided in this report. In no event will SRP or Nexant be liable for the failure of the customer to achieve a specified amount of energy or demand savings, the operation of the customer s facilities, or any incidental or consequential damages of any kind in connection with this report or the installation of evaluated measures. Business Solutions Retrocommissioning Program i

3 Contents EXECUTIVE SUMMARY... ES-1 SECTION 1 PROJECT CONTACTS SECTION 2 INTRODUCTION SECTION 3 BUILDING DESCRIPTION SECTION 4 PRELIMINARY ASSESSMENT SECTION 5 PROJECT PLAN APPENDIX A BUILDING SITE ASSESSMENT FORM... A-1 APPENDIX B UTILITY BILLING HISTORY... B-1 APPENDIX C CUSTOMER SELECTION FORM... C-1 Business Solutions Retrocommissioning Program i

4 Executive Summary Nexant performed a retrocommissioning planning phase assessment at Poston Butte High School through the SRP Business Solutions Retrocommissioning Program to determine potential energy saving opportunities. This is the first step in the process of improving building performance by tuning the existing building systems to operate optimally. One of the largest savings opportunities is optimizing the airside equipment. This involves tightening the air handler schedules so the occupied schedules better reflect actual occupancy times and implementing a discharge air temperature reset to allow the cooling system to meet load at design cooling conditions. Another measure that will generate substantial energy savings is the elimination of secondary, primary, and condenser water pumping when outside air drybulb temperature is between 40 F 55 F. Based on the implementation cost, payback period, and energy savings, it is recommended that this project proceed to the implementation phase. Table ES.1 shows the cost, savings and payback for the recommended measures. Please note that the savings achieved through these retrocommissioning measures exceeds the savings target of 215,000 kwh for this project. RCM No. RCM Description Table ES-1. Preliminary RCM Estimates Annual Energy Savings (kwh/yr) Peak Demand Savings (kw) Annual Electric Energy Cost Savings ($/yr) Implementation Cost ($) 1 Airside Optimization 159,308 0 $12,554 $7, Pumping Optimization 67,521 0 $5,321 $4, Simple Payback (years) Total 226,829 0 $17,875 $11, Business Solutions Retrocommissioning Program ES-1

5 Section 1 Project Contacts OWNER / OWNER REPRESENTATIVE John Schreur Director of Construction and Public Relations Florence Unified School District 1000 South Main Street Florence, Arizona P: F: E: jschreur@fusdaz.org SRP Charlie Gruber Senior Account Manager SRP MS ISB 231 PO Box Phoenix, AZ P: F: E: charlie.gruber@srpnet.com RETROCOMMISSIONING PROJECT ADMINISTRATOR Darren Gest, PE Nexant, Inc W Ray Rd, Suite 230 Chandler, AZ P: F: E: dgest@nexant.com or SaveWithSRPBiz@srpnet.com QSP Jim Zarske, PE, CEM Senior Project Manager Nexant, Inc. 867 Coal Creek Circle, Suite 120 Louisville, Colorado P: F: E: jzarske@nexant.com Business Solutions Retrocommissioning Program 1-1

6 Section 2 Introduction SRP s Business Solutions Retrocommissioning Program targets savings opportunities through the systematic evaluation of electric energy-using systems and the subsequent implementation of no-cost and low-cost measures. The program also provides an opportunity for your staff to work hand-in-hand with expert engineers to increase their knowledge of the efficient and effective operation of building systems. The program administrative process for each project follows four basic program phases: 1) Application Phase 2) Planning Phase 3) Implementation Phase 4) Verification Phase 2.1 PROJECT OBJECTIVES Most buildings have never gone through a formal, systematic commissioning or quality assurance process, and are likely performing below their potential. This program is designed to assist in improving building performance, and in the process capture the energy and demand savings opportunities. Retrocommissioning not only identifies problems due to design flaws or events that occurred during construction, just as traditional commissioning of a new building does, but it also identifies and recommends solutions to problems that have developed during the building s existence. Efficient operation of existing major building systems presents a significant potential for energy and demand savings, usually with little or no capital investment. A key goal of the retrocommissioning process involves achieving this efficient operation. Retrocommissioning seeks to assist with equipment and system functionality, and optimizing their integrated operation to reduce energy waste and improve building performance and occupant comfort. The goals of the retrocommissioning effort are as follows: reduction in peak electrical demand and related costs reduction in annual electrical consumption and annual costs improved building system control and occupant comfort 2.2 PROJECT SCOPE When the application is approved by the Program Administrator, the retrocommissioning process begins with the Planning Phase, which consists of identification of project objectives, targeting of systems for improvements, and defining tasks and responsibilities. A plan for conducting more detailed investigations is developed as a result. An Implementation Phase follows, in which an on-site equipment assessment and testing are conducted. This phase identifies additional system deficiencies and opportunities for improvement, estimates their economic potential, and defines an implementation scope of work for you to follow in order to implement the measures. Once the improvements are made in the Implementation Phase, and their success is validated through a final investigation, revised calculations are performed in the Verification Phase. The retrocommissioning procedures focus on electric energy savings opportunities with low implementation costs. Capital measures that are identified through the Retrocommissioning Program may be directed to SRP s Business Solutions Standard or Custom Business Program offerings. The Retrocommissioning Program does not address fire and life safety or basic equipment safety controls. Additionally, the program does not provide services for new construction or to meet commissioning requirements of other rebate programs offered by SRP. Business Solutions Retrocommissioning Program 2-1

7 Section 3 Building Description 3.1 GENERAL Poston Butte High School (PBHS) was constructed in 2009 and is located in San Tan Valley, Arizona. The school is a single building comprised of 250,377 square feet between 2 floors and 7 distinct areas. Areas B, D, and E are all classroom wings and are centrally connected by the large A area that houses the library and administrative offices. The southeast section of the A area connects to C which is the cafeteria. Moving south from this zone leads to the H area where the practice gym and culinary arts areas are located. The most eastern part of the building is the G area where the gymnasium and locker facilities are located. Onsite staff stated that exterior walls of the building are not insulated, which makes the building particularly sensitive to extreme outdoor air temperatures. However, trend data does not support sensitivity in building space temperature. Instead, it appears that a majority of the space comfort issues are caused by a combination of improper discharge air temperature settings, poor cooling valve responsiveness to zone temperature readings, and high minimum outside air percentage setpoints for many of the air handlers. The school currently has 1,820 students and is designed for 2,000. The school year runs from July 8 th through May 30 th, including administrative/teacher only days. Administrative hours are from 6:30 am until 4:30 pm, class is in session from 7 am until 2:45 pm, and janitors are present from 3:00 pm until 11:30 pm. All schedules are Monday through Friday and do not include extracurricular activities. In total, there are 180 school days for students and a maximum of 192 days for teachers. Further detail regarding the facility, its operation, and current conditions are provided in Appendix A Building Site Assessment Form. 3.2 ENERGY USE ANALYSIS Salt River Project (SRP) serves PBHS on two accounts that are on the E-32 time-of-use general service rate plan. This rate has monthly service charges as well as charges based on demand (kw) and consumption (kwh). The magnitude of each charge depends on the time-of-day and season in which the use occurs. This facility uses kwh/sq. ft. compared to an average secondary school that uses kwh/sq. ft. PBHS and Florence Union School District staff were concerned with the heating, ventilating, and air conditioning (HVAC) system s ability to adequately cool the building and have been considering taking capital-intensive measures to solve the problem. Yet another factor to consider is that the building is not meeting temperature setpoint on hot days. There is the possibility that the HVAC system is not ramping up cooling capacity as the design intended and, if corrected, energy use could actually increase as a result of the system increasing power consumption in order to meet building setpoints. This is not to say that overall energy use cannot be reduced through other measures. Figure 3-1 shows electric use and demand at PBHS over a full year of operation. These values are summed from the two electric meters for the school. The shape of the consumption history figure further bolsters the idea that the HVAC system is not ramping up in the summer; high energy consumption with moderate demand in the summer months is indicative of longer equipment run times. These longer equipment run times can often be attributed to a system that attempts to reach building space temperatures by running longer at a lower capacity instead of increasing capacity for a shorter amount of time. This type of operation could keep demand lower, but it doesn t allow the school to stay cool. Electric consumption and demand in the shoulder seasons is expectedly low: it is during these times that more moderate outside air temperatures occur and the corresponding HVAC system load is lowest. The energy use trends in the winter are typical of a building that uses electricity as the primary means of space heating. The highest annual demand occurs during winter and consumption is slightly above average. The winter profile is typical of a system that achieves building space temperatures by boosting capacity for a short period of time and Business Solutions Retrocommissioning Program 3-1

8 Section 3 Building Information then maintains it throughout the day at a lower capacity. This is in contrast to the summer months in which the system appears to be constantly chasing building temperature setpoints. When this consumption profile is cross-referenced with the school calendar it does not appear that building occupancy has a large effect on energy consumption, but rather energy consumption/demand is better predicted by outside air temperature. To an extent this is expected, especially since the building is poorly insulated. However, in months where there are a high number of intersession days and/or holidays it would be expected that energy use would be lower with less people in the building. The findings in the consumption history show that there is likely room for improvement in how the building operates in cooling mode and that tighter building schedules could be implemented. Table 3-1 has the tabulated monthly electricity use that Figure 3-1 is based on. Figure 3-1 Monthly Electricity Usage Table 3-1 Monthly Electric Usage Bill Date Days in Bill Total Load Total kwh Period Demand Factor* Aug ,914 43% Sep ,555 41% Oct ,779 40% Nov ,674 37% Dec , ,521 25% Jan , ,580 27% Feb , ,830 29% Mar ,005 27% Apr ,888 31% May ,128 40% Jun ,285 37% Jul ,917 36% Total 371-2,534,076 - Average ,173 34% *LOAD FACTOR IS DEFINED AS THE AVERAGE LOAD DIVIDED BY THE PEAK LOAD IN A GIVEN MONTH Business Solutions Retrocommissioning Program 3-2

9 Section 3 Building Information BUILDING EQUIPMENT PBHS utilizes a built-up central plant system for HVAC that is controlled by a sophisticated building automation system (BAS). Chilled water is provided by two (2) water-cooled centrifugal chillers set up in a lead/lag configuration. Chilled water is distributed throughout the building with a constant volume primary pumping loop and a variable volume secondary loop. Each chiller has a dedicated cooling tower and flat-plate heat exchanger, which allows the system to go into water-side economizer (WSE) cooling mode. Chilled water is delivered to a variety of equipment including both constant volume (CV) and variable air volume (VAV) air handling units (AHUs), energy recovery ventilators (ERVs), and fan coil units (FCUs). CV AHUs that have cooling coils and electric reheat typically supply air directly to spaces. VAV AHUs have cooling coils only and typically supply air to VAV boxes that use electric reheat. Most ERVs are used to precondition air that passes through FCUs with electric reheat or for larger AHUs. Those that have cooling coils and electric heat supply air directly to spaces. Some of the VAV AHUs have electric heating, but only the box level heating is in use. The Niagara BAS allows for automated, direct digital control (DDC) and visualization of every component within the HVAC system. The system is programmed to maintain indoor space temperatures from occupied and unoccupied schedules. Additionally, the system monitors outdoor air (OA) drybulb, wetbulb, and enthalpy to determine modes of operation including free-cooling, heating/cooling lockouts, and cooling plant enable. PBHS is currently utilizing many features of the BAS, but the HVAC schedule for most of the building extends far beyond when administrative hours end, which causes the system to use additional energy. Table 3-2. Building Equipment List Equipment Item Description Capacity / Size Area Served (2) Centrifugal Chillers (2) Flat-Plate Heat Exchangers (2) VFD Cooling Towers (2) Primary CHW Pumps (2) VFD Secondary CHW Pumps (9) CV AHUs (5) VAV AHUs York M#: YKADADQ4-CKF Alfa Laval M15B-BFG Evapco AT Ton Ea. Entire Building 4,803 kbtuh / 400 Ton Ea. 400 Ton / 2,400 GPM Ea. / 20HP Fans Entire Building Entire Building Taco FI GPM / 15 HP Ea. Primary CHW Loop Taco FI6013 York XTO, CHW, Electric Heat York XTO/XTI, CHW, Electric Heat* 1,725 GPM / 75 HP Ea. Various, ,400 CFM Various, 4,450-12,587 CFM Secondary CHW Loop / Entire Building Various Large Areas (ex: Gym, Chorus) Various (1) VAV AHU York, CHW 16,783 CFM Practice Gym (7) ERVs (6) ERVs (1) ERV (63) FCUs (22) VAV Boxes Greenheck ERV- 522H-30B Greenheck ERCH CHW, Electric Heat Greenheck APEX- 200H-30 CHW York AHI, CHW, Electric Heat Trane VCEF, Electric Reheat Various, 1,600-11,600 CFM Various, 1,950-5,780 CFM Various, preconditions air for FCUs Various 20,000 CFM / 15 HP Main Gym Various, 800-3,000 CFM Various, 60-3,640 CFM Classrooms Various Business Solutions Retrocommissioning Program 3-3

10 Section 4 Preliminary Assessment The retrocommissioning process begins with the Planning Phase, which consists of identification of project objectives, targeting of systems for improvements, and defining tasks and responsibilities. The target annual energy savings for this project is 215,000 kwh/year. If the recommended RCMs are incorporated (see table below), the projected energy savings total is 226,829 kwh/year. The calculated energy savings is only an estimation of energy savings based on the brief information gathered during the Planning Phase. During the Implementation Phase of this project, more in-depth equipment assessment and testing will be conducted. Trend data are also collected for equipment operating parameters including run times, temperatures, and set points. After reviewing the facility drawings, interviewing the facilities staff, and exploring the Building Automation system, Nexant has generated a list of measures for consideration by the customer. The following table summarizes the overall savings and also details the measures proposed. Additional measures will be considered further in the Implementation Phase of this project. RCM No. RCM Description Table 4-1. Preliminary RCM Estimates Annual Energy Savings (kwh/yr) Peak Demand Savings (kw) Annual Electric Energy Cost Savings ($/yr) Implementation Cost ($) 1 Airside Optimization 159,308 0 $12,554 $7, Pumping Optimization 67,521 0 $5,321 $4, Simple Payback (years) Total 226,829 0 $17,875 $11, Business Solutions Retrocommissioning Program 4-1

11 Section 4 Preliminary Assessment 4.1 RETROCOMMISSIONING MEASURES RCM No. Measure Description Energy Savings (kwh/yr) Peak Demand Savings (kw) Implementation Cost ($) 1. Airside Optimization 159,308 - $7,000 Current Conditions: Review of schedules for the BAS system showed that the majority of the airside equipment (AHUs, ERVs, and FCUs) are starting at 5:00am and running until 9pm. In many cases the supply air temperature (SAT) in the cooling season is not low enough during occupied hours, resulting in space temperatures that do not achieve the setpoint of 72 degrees. Proposed Changes: Using the existing BAS scheduling program, the airside equipment s operating hours can be reduced by a minimum of 2 hours per day during the week. The CV AHUs and ERVs should have a SAT reset so adequate cooling is possible in those spaces. This will increase energy use but will allow for increased occupant comfort. Technical & Physical Feasibility: The measure will require review of schedules and discussions with the facility staff to verify exactly when the units need to be supplying air to the space. Changes to schedules will require intermediate skill level to interact with the BAS system. Measure Persistence: Estimated life for this measure is long. Some minor changes to the schedules may be needed on a yearly basis. Trending Requirements: Fan operating status, fan speed, outside air temperature (OAT), supply air temperature (SAT), mixed air temperature (MAT), return air temperature (RAT), outside air damper position, ERU discharge and exhaust temperatures, chiller energy use, secondary pump speed and primary pump status, cooling tower speed, secondary chilled water supply and return temperatures, energy use and tonnage, AHU heating & VAV reheat status/percentages Owner Buy-in: Measure should be acceptable to the customer due to the limited amount of work and low cost involved. Measure Cost: Cost is estimated based on 40 hours at $150/hour of programming needed to adjust the schedules and temperature resets. Commissioning of the controls once they have been updated will cost an additional $1, Pumping Optimization 67,521 - $4,600 Current Conditions: The primary, secondary, and condenser water pumps and one cooling tower fan run throughout the year even when OA temperatures are favorable for airside economizing and high enough such that there is no risk of freeze (60-45 ). Proposed Changes: As a conservative start, the operation of one set of condenser, primary, and secondary pumps can be turned off for OA temperatures between 45 and 60 year round and an additional 1.5 hours overnight on a daily basis. Technical & Physical Feasibility: During periods where these conditions are satisfied there should not be a need for chilled water since the building will either be in heating mode or airside economizer mode for cooling purposes. There is not a risk of freezing when the pumps are off in this temperature range and the building should allow the AHU freeze stats to control when pumps cycle on for freeze protection. Business Solutions Retrocommissioning Program 4-2

12 Section 4 Preliminary Assessment RCM No. Measure Description Energy Savings (kwh/yr) Measure Persistence: Estimated life for this measure is long (>10 years). Peak Demand Savings (kw) Implementation Cost ($) Trending Requirements: Plant enable, P1, P2, P3, P4, P5, and P6 operating status, pump speed for P1 & P2. This last trend requirement doesn t appear to be recorded in the BAS history. Owner Buy-in: Measure should be acceptable to the customer due to the limited amount of work and low cost involved. Measure Cost: Cost is estimated based on 24 hours at $150/hour of programming needed to adjust the schedules. Commissioning of the controls once they have been updated will be an additional $1, ADDITIONAL MEASURES RCM No. Measure Description Energy Savings (kwh/yr) Peak Demand Savings (kw) Implementation Cost ($) 3. VAV AHU supply fan speed optimization TBD TBD TBD Current Conditions: VAV AHU s fan speed doesn t change much throughout the day, indicating that the VAV box dampers do not modulate or are constantly in active heating or cooling. Proposed Changes: Use the existing BAS and trend data to diagnose what existing condition or control sequence is keeping the VAV AHU s with such a consistently high fan speed percentage. 4. Install CO2 sensors to control AHU OA% TBD TBD TBD Current Conditions: The majority of AHU s onsite have between 20-40% outside air minimum setpoints, which consumes unnecessary chiller plant energy when space cooling is required. Proposed Changes: Install CO2 sensors to control certain AHU s to a lower minimum outside air percentage based upon actual occupancy, which should save substantial cooling energy. 5. Investigate CHW valve PID programming TBD TBD TBD Current Conditions: Most Constant Volume AHU s will supply 55 SAT in the morning and the valve modulates appropriately, but during occupied hours the valve position spikes and then goes to 0 and rarely settles on a steady operating point. Proposed Changes: Use the existing BAS and trend data to diagnose what existing condition or control sequence is keeping the CHW valves from modulating properly. Business Solutions Retrocommissioning Program 4-3

13 Section 4 Preliminary Assessment 6. Chiller Plant Optimization TBD TBD TBD Current Conditions: The current condenser water temperatures are high and chiller staging can be improved upon. Proposed Changes: Using the existing BAS and trend data to diagnose what existing conditions or control sequences are operating properly. 7. Network Computer Power Management TBD TBD TBD Current Conditions: Unknown Proposed Changes: Installation of network computer power management software can reduce energy use by placing computers and monitors in a sleep mode after a period of inactivity automatically from the central network connection. 4.3 RECOMMENDATIONS Based on preliminary identification of the RCMs listed above, which provide a total estimated energy savings of 226,829 kwh/year and thus exceed the savings goal of 215,000 kwh/year, it is recommended that this project proceed into the implementation phase. Business Solutions Retrocommissioning Program 4-4

14 Section 5 Project Plan 5.1 ROLES AND RESPONSIBILITIES Program Administrator Serve as project manager. Facilitate the gathering of project information as needed by the QSP. Work with the QSP to determine the and how to best leverage existing resources to streamline the project and reduce costs. Support the QSP s efforts to accomplish the work. Define the lines of communication between the team members. Support the QSP by facilitating communication between the QSP and other project team members as needed. Owner / Owner Representative Provide contact person for facilitating communications. Gather building documentation. Assist and provide detailed input into the initial assessment and investigation process, to also include such items as: O&M methods and procedures Service contract information Equipment condition and operational constraints Keep the building occupants informed of the intended retrocommissioning work, as needed. Provide technician to assist QSP for retrocommissioning activities in the building. Provide an Energy Management System (EMS) programmer to investigate program changes. Gather trending information from the EMS, as recommended by QSP. Assist with the performance of functional testing, as needed. Perform appropriate preventive maintenance and complete any pre-requisite tasks requested by the QSP prior to any diagnostic or functional testing. Identify and coordinate building work protocol for retrocommissioning team members, such as: Security and access Restrictions on special areas in the building (sensitive tenants, etc.) Restrictions on photos or videos (building-wide or in certain areas) Necessary identification Parking permits Safety and emergency requirements and contacts Need for escort while in the building or in special areas of the building Business Solutions Retrocommissioning Program 5-1

15 Section 5 Project Plan Special protocols when entering tenant spaces (e.g., the most acceptable times for performing work in tenant spaces). Attend training sessions and retrocommissioning meetings. Update and maintain Customer Selection Form Retrocommissioning Service Provider (QSP) Identify documentation, drawings, data, and other information required from facility staff. Develop a building-specific retrocommissioning report. Update and maintain Customer Selection Form Propose a schedule for review and acceptance by the team members. Perform a detailed on-site assessment of the present maintenance practices and operating strategies, noting all possible improvements. Review the service contracts in effect and make recommendations to how they may be improved to ensure that the equipment operates efficiently. Develop monitoring and testing plans. Perform short-term diagnostic monitoring, using EMS trend-logging where appropriate. Develop, oversee, and document the functional test procedures as needed. Install and remove short-term diagnostic monitoring equipment. Recommend system or energy-efficient capital improvements on electricity-using systems for further investigation. Prioritize for implementation the most cost-effective improvements of existing systems. Perform post-installation verification, monitoring and testing activities. Calculate the estimated electrical energy savings. Develop methods for the owner and building staff to continue to track the performance of the improvements. Submit a final report and all specified deliverables, such as: Project schedule specific for the building Meeting minutes Completed assessment forms Diagnostic monitoring, trending, and functional test plans Completed functional performance tests List of recommended improvements for immediate implementation (based on costeffectiveness) Business Solutions Retrocommissioning Program 5-2

16 Section 5 Project Plan List of recommendations for capital improvements for further investigation Final energy saving estimates and calculations Retrocommissioning schedule Updated/revised building documentation Provide follow-up service and troubleshooting as needed. 5.2 PROJECT SCHEDULE The proposed project schedule is summarized in Table 5-1. Retrocommissioning Project Schedule Table 5-1. Retrocommissioning Project Schedule Project Phase Tasks Deliverable Due Date Planning Visit building to meet with owner to discuss project goals Collect building documentation Develop project Retrocommissioning Plan March 2014 Implementation Perform detailed site assessment Compile list of deficiencies Develop diagnostic and calculation plan Conduct testing and monitoring Select measures for recommendation Estimate demand and energy savings for recommended measures Develop implementation verification procedures for recommended measures Present updated Customer Selection Form Building owner implements measures as investigation is completed Updated Customer Selection Form (8-20 weeks following plan acceptance) Verification Conduct on-site verification of measure implementation Review Verification Report Verification Report (3-10 weeks following project completion) Business Solutions Retrocommissioning Program 5-3

17 Appendix A Building Site Assessment Form General Information QSP: Nexant, Inc. Project name: Poston Butte High School Project number: RCS02_ Facility address: N Gantzel Rd Facility city, state, zip: San Tan Valley, Arizona Building Characteristics Characteristic Description Year of construction 2009 Gross area (gross square footage) 250,377 Percent of gross area designated as prime office space Percent of gross area designated as computer data center space Percentage and type of other secondary space uses (e.g. parking, clarify below if necessary) Building configuration (e.g. campus, towers, low-rise) Building use (e.g. office, school, hospital) Number of floors (levels) 2 Number of occupants Annual occupancy rate of primary space by year NA NA 0 Campus Number of personal computers in operation (approx.) 300+ Type of lighting equipment installed (e.g. T12, T8, HID) Weekly hours of operation by major space type High School ~1,820 Students T8 Year Occupancy Rate (%) 2011 Approximately 100% 2012 Approximately 100% 2013 Approximately 100% Space type Hours/week Staff Hours 6:30a 4:30p Classroom 7:00a 2:45p Extracurricular Various Building occupied for 11 or more of last 12 months? Brief renovation history Brief description of building improvements planned Yes None RCx measures only at this point Business Solutions Retrocommissioning Program A-1

18 Section 5 Project Plan Building Equipment Equipment Type of cooling system (e.g. central plant, district cooling, packaged A/C) Type of condenser (e.g. air or water, number of cells) HVAC distribution system (e.g. constant volume, variable volume, dual duct, multi-zone) Age of primary cooling system 4 Heating system type HVAC control system type (e.g. pneumatic, DDC) Brief equipment replacement / renovation history Building Control Systems Central Plant Chilled Water Description Water, 2 Cells, 1 Cell per Chiller VAV & CV AHU s, ERV s, VAV boxes, FCU s Electric Heating Coils in AHU s and also terminal electric reheat DDC Niagara BAS Original Equipment Equipment Does facility use a zone temperature setup/setback strategy? Is the central supply air temperature fixed or is a reset strategy used? Does central air system have pre-heat? Is free cooling used, i.e. with an air or water-side economizer? How is the outdoor air controlled? What is the design minimum outdoor air fraction? For VAV systems, is a supply static pressure reset strategy used? Does system have automatic shutdown? Is an optimum start strategy used? Is system equipped with zone isolation devices for minimizing energy use in off-hour operation? Is there exhaust air heat recovery? Yes Reset, not fully effective Yes at most AHU s Description Yes based on OAT and enthalpy Adjustable OAD controlled by BAS. Min OAD percent determined during TAB, varies between Airside equipment No, a single setpoint is used Yes, based on schedule Trend data indicates there might be a morning heatup/cool down, but there is nothing indicated in the control sequences Yes, but are not being fully utilized Yes Business Solutions Retrocommissioning Program 2

19 Section 5 Project Plan Has the heating system always met load? Yes General O&M Issues If no, under what conditions has the heating system not met load? What was the approach to solve this problem? Has the cooling system always met load? No If no, under what conditions has your cooling system not met load? Design days only in certain areas. SAT reset not correct. What was the approach to solve this problem? Current approach by facilities staff is to override the Outside Air % on AHU s to 0% when not able to meet load. Is any free cooling used? Yes If yes, please describe. The Energy Recovery Ventilators and airside and waterside economizers are controlled by OAT and enthalpy Is there any HVAC equipment that is considered to be undersized? Yes If yes, explain: Potentially 1 AHU that can t reach setpoint even with manual overrides (AHU2 library). What compensation is made for the under sizing? None, area is warm Is there any HVAC equipment that is considered to be oversized? No If yes, explain: What compensation is made for the over sizing? Business Solutions Retrocommissioning Program 3

20 Section 5 Project Plan Is the facility mechanical equipment (fans, pumps, etc.) scheduled to start up simultaneously, or is the startup staged? Slightly staged depending on status of critical components. What HVAC adjustments are made to unoccupied areas or spaces (e.g., turn off HVAC, adjust thermostat to minimum heating and cooling, close off diffuser)? Unoccupied temperature setpoints are employed; AHU s and terminal devices only come on to maintain unoccupied setpoints. Is the facility HVAC system airflow correctly balanced? Yes and No If yes, when was it completed? 2009 If no, explain: While we have seen the Testing and Air Balance (TAB) reports for the building from 2009, it does not appear that all balancing properly tuned the equipment onsite. Some of the Air Handlers for example were passed on their TAB report even though they only output approximately 90% of the design airflow. This substantially reduces the ability for that AHU to meet the cooling load it was designed to handle. Are there any problems with the humidification method (explain)? None known If yes, explain: Describe the method of humidification for the building: Humidification from ERV s only From what areas in the facility are the most complaints received (explain nature of complaints)? Library What is the worst facility problem and how is it managed? Space too warm, OA % set to zero and still doesn t meet load. Do you have a procedure for systematically identifying areas of excessive energy usage? No If yes, describe: Business Solutions Retrocommissioning Program 4

21 Section 5 Project Plan Does the building facilities team have specific goals established for improving the building mechanical systems? No If yes, describe: In the past year, have modifications been made to improve the facility s energy efficiency? No If yes, describe: Business Solutions Retrocommissioning Program 5

22 Section 5 Project Plan Notes, Comments, and Observations from Facilities Manager The facilities manager Rogelio made mention of a number of concerns regarding the operation of the building systems which included: It appears that the Energy Recovery Ventilators (ERV s) are not operating their heat transfer wheels at times he feels they should and he has to turn off and turn back on the units to get them to start. The Library had problems meeting load and due to that fact he manually overrides the AHU outside air percentage to 0%. He also does this for other AHU s. The school district has been considering adding another cooling tower to address the problems with maintaining comfort in the building. Additional notes, comments, and observations from QSP Business Solutions Retrocommissioning Program 6

23 Appendix B Utility Billing History Bill Date Days in Bill Total Load Total kwh Period Demand Factor* Aug ,914 43% Sep ,555 41% Oct ,779 40% Nov ,674 37% Dec , ,521 25% Jan , ,580 27% Feb , ,830 29% Mar ,005 27% Apr ,888 31% May ,128 40% Jun ,285 37% Jul ,917 36% Total 371-2,534,076 - Average ,173 34% *LOAD FACTOR IS DEFINED AS THE AVERAGE LOAD DIVIDED BY THE PEAK LOAD IN A GIVEN MONTH Business Solutions Retrocommissioning Program B-1

24 Appendix C Customer Selection Form SRP Business Solutions Retrocommissioning Program Project: Poston Butte High School QSP: Nexant, Inc. Description: Owner RCM Selection Table Phase: Planning Edit Date: 3 /10/2014 Measure Description Savings Summary RCM Bundle 1 RCM Bundle 2 RCM Bundle 3 Measure Selected by Owner 1 (X) RCM No. Measure Description Interaction Factor Peak Dem and Savings (kw) Annual Energy Savings (kwh/yr) Electrical Cost Savings ($/yr) Measure Increm ental Cost ($) Sim ple Payback (yrs) X X X X 1 Airside Optimization 1-159,308 $12,554 $7, X X X X 2 Pumping Optimization 1-67,521 $5,321 $4, Totals (For all Selected (X) values only) - 226,829 $17,875 $11, Retrocom m issioning Bundle 1 Retrocom m issioning Bundle 2 Retrocom m issioning Bundle 3-226,829 $17,875 $11, ,829 $17,875 $11, ,829 $17,875 $11, Business Solutions Retrocommissioning Program C-1

25 Retrocommissioning Program Information Hotline: (602)