THE PENNSYLVANIA STATE UNIVERSITY DEPARTMENT OF ARCHITECTURAL ENGINEERING THESIS NEW INDEPENDENCE HIGH SCHOOL/SHARED USE FACILITY

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1 MECHANICAL TECHNICAL ASSIGNMENT 2B John Shaw

2 EXECUTIVE SUMMARY The Mechanical Technical Assignment 2b involves an evaluation and comparison of the student thesis project cooling loads and energy costs. First, the assignment requires that building cooling loads and energy costs be determined using simplified hand calculation methods, then through the use of load and energy calculation software for comparison to the design loads. In addition, the assignment requires and inquiry to the Design Professional if energy analysis was conducted for the project. The department assignment 2b outlines more detailed information for submission. When using the Trane Trace700 software to compare loads and energy use, several differences result when compared to the hand and design calculations. Assignment time constraints prevent a detailed investigation of the software to determine the probable errors. However, further study is required. Overall the hand calculations resulted in similar values to the design calculations. To achieve realistic results, diversity factors were applied to the hand calculations based on comments from the Acting Mechanical Design Professional. As typical with buildings of this type and size, the Design Professional did not conduct formal energy analysis. Software technical issues prevented achieving the energy cost results even though the probable energy demand was calculated. 29OCT03-2 -

3 Introduction Mechanical Technical Assignment 2b involves an evaluation and comparison of the student thesis project cooling loads and energy costs. First, the assignment requires that building cooling loads and energy costs be determined using simplified hand calculation methods, then through the use of load and energy calculation software for comparison to the design loads. In addition, the assignment requires and inquiry to the Design Professional if energy analysis was conducted for the project. The department assignment 2b outlines more detailed information for submission. Project Background The New Independence High School Shared Use Facility grew from a need first proposed by Independence Schools district, Independence, Ohio in 1995 and evolved into the facility currently in construction. The community, through its own active design input and financial support shares the facility with the Independence Schools District. The facility is a 194,403 square foot, 33 million dollar, two level new high school education building with shared facilities for community use. Sear-Brown provided Architectural, Site, Structural, Mechanical, Electrical, Plumbing, and Fire Suppression design services supported by Then Design Architecture Ltd and R.C.A.L. Architects Inc. Interestingly, the architects chose a colonial/federalist style for the architectural feel to integrate with local building styles. This style provides a sturdy, modern, long term look of stability to reassure both students and community residents of the school district s and city s commitment to secondary education and community activities. In early 2003 Independence Schools and City of Independence received bids, offered multiple prime construction contracts to approximately 22 prime contractors and selected Turner Construction to provide construction management services for this traditional design, bid, build project. Independence Schools desires the project construction completion to occur prior to the beginning of the fall 2004 school year. Assignment 2b General Assumptions and Clarifications In order to complete the assignment, the following assumptions and clarifications apply: This report makes no attempt to discredit or criticize the original Design Professional s design assumptions, design basis, or design constraints. This report fulfills a purely academic education exercise and is required for the Penn State Architectural Engineering Senior Project Thesis. This report author assumes no 29OCT03-3 -

4 liability for the reader s misuse, misstatements, or misinterpretations of the conclusions or content contained within this report. The New Independence High School Shared Use Facility project is part two of a two phase project. Part one involves a renovation to the existing high school with conversion to the Renovated Middle School. Incomplete mechanical and electrical information prevents including this phase in thesis. Therefore all project terms in this report refer to the New Independence High School Shared Use Facility only. This phase shall remain the focus throughout the thesis. Inconsistencies between the student assumptions, software calculation algorithms, and the Design Professional s basis of design obviously prevent the exact same results. Construction documents do not indicate every load assumption or equipment used for system sizing. The assignment intent involves establishing similar load assumptions and conducting calculations to demonstrate knowledge of the calculation methods and knowledge of the student thesis building loads. Use of load and energy calculation software requires a thorough understanding of the software calculation algorithms for realistic results. This prevents the garbage in, garbage out dilemma. Results from these programs requires experience and evaluation with rule-of-thumb checks for result validation. In-sufficient time prevents more accurate results from the Trane, Trace700 software use The assignment focuses on cooling, not heating, for the load calculation portion. Therefore this report author only includes the systems that provide cooling. This assignment involves less formal writing, but more spreadsheet or table format data with brief statements of results, assumptions, etc. Drawing schedules were utilized for this report but are NOT included in this report. The instructor may review these schedules per request. For the load calculation section and since every part of the facility does NOT peak in cooling demand simultaneously, diversity factors were applied for the energy calculations. Appendix A contains relevant diagrams, tables, and schematics (based on construction documents and specifications). Due to the sensitive nature of this information and respect for the Owner s privacy, appendix A shall NOT be posted to the internet. A hard copy shall be printed and delivered to the Assignment 2b instructor. Assignment 2b Load Calculation This section includes a summary of the cooling load calculation results in table format. This report author recommends the reader review the comments, exclusions, and assumptions section and Appendix A spreadsheets for background information. Due to 29OCT03-4 -

5 the calculation details, this report author may inadvertently neglect stating some formula or calculation method used to obtain a particular result. If the instructor questions a calculation, the report author recommends the instructor inquire so a clarification or explanation may be made. Per the assignment direction, this section estimates the design cooling load using data, such as outdoor ventilation rates or lighting load, from the construction documents and possibly the specifications. Calculation design indoor and outdoor air conditions comply with ASHRAE Fundamentals 2001 (.4%). Results summary: ITEM HAND CALC SOFTWARE DESIGN GRAND TOTAL Total (ton w/o diversity factors) Supply Air (cfm-w/o diversity) 212, , ,125 Includes (sp load, vent, exh) Ventilation Air (cfm-not incl mua 94,625 80,203 94,625 for exhaust) Supply Air / SqFt Ventilation Air / SqFt Cooling SqFt / Ton Typical Range = sqft/ton for classroom type space Energy Calculation This section includes a summary of the energy calculation results in table format. This report author recommends the reader review the comments, exclusions, and assumptions section for background information later in this section. Due to the calculation details, this report author may inadvertently neglect stating some formula or calculation method used to obtain a particular result. If the instructor questions a calculation, the report author recommends the instructor inquire so a clarification or explanation may be made. Per the assignment direction, this section estimates the design energy consumption using data, such as loads, fuel costs, and equipment kw, from the construction documents and possibly the specifications. In addition, this assignment requires the determination if the Design Professional conducted energy analysis for the project. The original Mechanical Design Professional is no longer with the Design Firm. An inquiry revealed that no energy analysis was conducted for this project and is typical for projects of this size. The system configuration concepts was guided by the Ohio Facilities Schools Commission. The State of Ohio Schools division mandates what type of systems shall be utilized in school facilities. 29OCT03-5 -

6 Results summary: ITEM HAND CALC w/ diversity factors SOFTWARE w/ less diversity factors DESIGN GRAND TOTAL Fans (kw-h) Not per equip N/A Air Cooled Chiller (kw-h) Not per equip Pumps (kw-h) Not per equip Boilers (kw-h) Not per equip Pumps (kw-h) Not per equip Misc Heating Equip (kw-h) Not per equip TOTAL (kw-h) 1,238, ,738,196 Electric Cost Ltg Sys & Gen Equip ($/yr) $37, Not per sys Cooling Plant ($/yr) $56, Not per sys Total ($) $94, Software Annual plant cooling cost ($/sqft) w diversity factors $0.47 Not calculating Comments, Assumptions, Exclustions Load Calculation These calculations are very simplified and generalized and do not account for every item or activity or load occurring within the facility. The assignment time constraints prevent a detailed study. Clearly the software date requires adjustment to obtain reasonable results Since the entire building does not reach max load at the same time, the actual design cooling load is approximately 328 ton. Per correspondence with the Acting Mechanical Design Professional, (2) chillers are installed per design, one acts as backup. To calculate the demand cooling, cfm, and ventilation loads, diversity factors were applied. The load calculations focus on cooling. Heating is not included. Approximately 62% of the facility is cooled. The athletic indoor field house and gymnasium are not cooled. 29OCT03-6 -

7 Energy Use These calculations are very simplified and generalized and do not account for every item or activity or load occurring within the facility. The assignment time constraints prevent a detailed study. Refer to Appendix A for Utility Rate Information. For purposes of the Hand Energy Calculations, only the Generation and Regulatory Transition Kw-H/KwD and Distribution Demand Charge shall be used. For purposes of completing the assignment, only KwH charges were used to determine energy use cost. Natural gas costs and demand for boilers were not included. Supplemental Electric charges used in real world situations, were not included. 29OCT03-7 -

8 Appendix A 29OCT03-8 -