The baseline building system for compliance with Senate Bill 668 is defined by Appendix G,

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1 Project: North Carolina A&T State University New Student Health Center SCO #: A 1.0 Heating, Ventilating and Air Conditioning (HVAC) Baseline Building Systems Senate Bill 668 Compliance The baseline building system for compliance with Senate Bill 668 is defined by Appendix G, ASHRAE Standard The building is nonresidential, has two floors (5 or less floors) and consists of 27,000 GSF (less than 75,000 GSF). The baseline HVAC system is System 3 Packaged Single Zone Rooftop Air Conditioner. The Climate Zone is 4A. The baseline system consists of packaged rooftop units with constant volume fan control and hot water reheat. Cooling is by direct-expansion refrigerant circuits. Heating water is provided by natural gas-fired boilers. Economizers (air and water) are not required in Zone 4A. Since we do not anticipate the project will have air supply systems over 5,000 CFM with minimum outside air of 70% or more; therefore exhaust air energy recovery is not required. Heating and cooling load and energy analyses will be based on the following envelope characteristics: a) Envelope opaque elements: Roof insulation above deck: U = 0.063, R15 continuous insulation Walls - mass: U = 0.151, R5.7 continuous insulation Walls steel framed: U = 0.124, R13 insulation b) Envelope for fenestration areas less than 40% of wall: U-fixed = 0.57 U-oper = 0.67 c) Fenestration less than 40% of wall: SHGC-all = 0.39 SHGC-north = 0.49 LEED NC version 3.0 Compliance The baseline building system for compliance with LEED NC version 3.0 is defined by Appendix G, ASHRAE Standard The building is nonresidential, has two floors (5 or less floors) and consists of 27,000 GSF (25,000 to 150,000 GSF). The baseline HVAC system is System 5 Packaged VAV Rooftop Air Conditioner with reheat. The Climate Zone is 4A. The baseline system consists of packaged rooftop units with variable volume fan control and hot water reheat. Cooling is by direct-expansion refrigerant circuits. Heating water is provided by natural gas-fired boilers. Economizers (air and water) are not required in Zone 4A. Since we do not anticipate the project will have air supply systems over 5,000 CFM with minimum outside air of Page 1 of 6

2 70% or more; therefore exhaust air energy recovery is not required. Terminal units will have a minimum of 0.4 cfm/sf airflow and hot water reheat coils. Heating and cooling load and energy analyses will be based on the following envelope characteristics: a) Envelope opaque elements: Roof insulation above deck: U = 0.048, R20 continuous insulation Walls - mass: U = 0.104, R9.5 continuous insulation Walls steel framed: U = 0.064, R13 insulation + R7.5 continuous insulation b) Envelope for fenestration areas less than 40% of wall: Non-metal framing: U = 0.40 Metal Framing (curtain wall/storefront): U = 0.50 Metal Framing (entrance door): U = 0.85 Metal Framing (all other): U = 0.55 c) Fenestration less than 40% of wall: SHGC-all = 0.40 Proposed Building Systems The proposed building design will include several general building design strategies. HVAC zoning will be optimized based on the building space program, grouping for separate systems, occupancy and operation schedules and conditions (24-hr vs. daytime only; lab/office/treatment etc. zones). Interior design conditions will meet, but not exceed, temperature and relative humidity (RH) requirements. Exceeding these can have a significant effect on the cost of energy, systems and controls. Criteria will be reviewed and confirmed with the owner. Various types of lights and sources will be considered, including T8, T5, LED, HID and task lighting. The type and use will be considered for the most appropriate and efficient application for each type of space. Also, specific strategies and options will be evaluated based on complete building energy models. Since Senate Bill 668 and LEED NC version 3.0 reference different baseline models; therefore two different baseline models will be compared to the proposed building models. Various fenestration-types, building orientation, shading devices, and daylighting (distributed evenly each exposure in the model) will be considered. Envelope performance will include several roof and wall insulation options. Proper outside air quantities, without over-ventilating, will be utilized. CO2 demand controlled ventilation will be evaluated. The proposed building will use a high efficiency chilled water system in lieu of packaged rooftop systems. Variable air volume (VAV) terminal systems will be used in lieu of constant volume systems, with variable speed drive air handling unit (AHU) fans. Terminal units will have a minimum of 30% airflow and hot water reheat coils. Fundamental economizer performance will be evaluated based on the building energy model (not required in the base building). Baseline fan power will be compared to a proposed reduced static pressure (using lower coil and duct velocities). Page 2 of 6

3 In addition to electrical sub-meters, natural gas and energy (BTU) meters will be provided so that HVAC system energy the savings can be measured and verified. System Alternatives: To meet or exceed the requirements of the energy bill of 30% greater energy efficiency than ASHRAE Standard , the following energy efficient strategies will be analyzed and Life Cycle Cost Analyses (LCCA) will be performed in accordance with SCO Guidelines for the following HVAC systems: 1. Air Handling Units Constant volume vs. VAV/RH will be analyzed. 2. Air Handling Units The use of air economizer cycle will be analyzed. 3. Chilled Water Systems Magnetic water cooled chillers vs. air cooled chillers and air-cooled heat pump chiller/heaters. 4. Heating Water Systems High efficiency condensing boilers vs. non-condensing boilers and air-cooled heat pump chiller/heaters. 2.0 Plumbing Systems The project goals include a minimum building water use reduction of 30% less than the water use baseline calculated for the building after meeting the Energy Policy Act of 1992 fixture performance requirements. The calculations are based on estimated occupant usage and include only the following fixture types: water closets, urinals, lavatory faucets, showers, and kitchen sinks. The Energy Policy Act of 1992 Flow Rate requirements are listed below: Energy Policy Act of 1992 Flow Requirement Fixture Water Closets Urinals Showerheads* Faucets* Replacement Aerators* Flow Rate 1.6 (gallons/flush) 1.0 (gallons/flush) 2.5 (gallons/min) 2.5 (gallons/min) 2.5 (gallons/min) * At 80 psi flowing water pressure Baseline Building Systems The baseline building service water heating system will consist of 80 % efficient natural gas-fired storage type water heaters with maximum allowable standby losses as defined by ASHRAE Water temperature controls are to be provided to limit the supply water temperature Page 3 of 6

4 to 110 F at lavatory faucets in public facility restrooms. Operating limit control will be provided for storage tank recirculation pumps to limit operation to a maximum of 5 minutes after the end of the heating cycle. Plumbing fixtures will have flow rates in compliance with the Energy Policy Act of 1992 as summarized above. Proposed Building Systems The following will be included in the building plumbing systems design: low flow water closets (1.28 GPF), low flow urinals (0.125 GPF) low flow (0.5 GPM) aerators for lavatory and sink faucets, low flow (1.8 GPM) showers, and automatic flow controls on lavatories and sinks to limit duration to 12 seconds. We are currently reviewing a study performed by John Hopkins University concerning the higher incidence of bacteria found in automatic faucets versus manual faucets in conjunction with the joint response issued by ASPE (American Society of Plumbing Engineers) and ASHE (American Society of Healthcare Engineers). System Alternatives: To meet or exceed the requirements of the energy bill of 30% energy and 20% building use water savings, the following energy efficient strategies will be analyzed and Life Cycle Cost Analyses (LCCA) performed in accordance with SCO Guidelines for the plumbing systems: 1) Service water heating Natural gas-fired condensing water heaters, electric water heaters and heat exchangers for the heating water boilers will be analyzed. 2) Air conditioning condensate recovery (roughly 70,000 gal/year) will be considered for use in irrigation and toilet flushing. Rain water harvesting (roughly 0.50 gal/sf per inch of rainfall) will also be considered and these two strategies may be combined. 3) If rainwater harvesting proves to be appropriate for this facility we will also consider capturing the water from fire protection system testing as well. In addition to electrical sub-meters, natural gas and water meters will be provided so that the energy and water consumption savings can be measured and verified. 3.0 Electrical Systems Baseline Building Systems Senate Bill 668 Compliance The baseline building interior lighting power densities for compliance with Senate Bill 668 will use 1.0 watts/sf as permitted by ASHRAE Standard , Table 9.5.1: Lighting Power Densities using the Building Area Method for the Health Care Clinic classification. The lighting system will consist of energy efficient T-5, T-8 and compact fluorescent lamp technologies with matching electronic ballasts. Fluorescent lamps will be Low-mercury or green fluorescent lamps and will have green markings to denote that they have passed the U.S. Federal EPA Toxicity Characteristic Leaching Procedure (TCLP). Page 4 of 6

5 Automatic lighting controls shall be provided in areas by either occupancy sensors or a programmable relay based lighting control panel(s). Occupancy sensors will be utilized to provide automatic lighting shut-off in, exam rooms, classrooms, conference rooms, and break rooms as required by Chapter 9 of ASHRAE Standard In accordance with ASHRAE , Appendix G, lighting controls for the baseline design will not have to be modeled. All other interior spaces within the building will be connected to the lighting control panel to provide scheduled time-of-day automatic lighting shut-off with local override switches. Dimming system controls will be utilized in spaces where applicable for the control of fluorescent lamps and for energy conservation. The baseline building exterior lighting system power densities will comply with ASHRAE Standard , Table 9.4.5: Lighting Power Densities for Building Exteriors and with Section for a minimum lamp efficacy of 60-lumens/watt. The baseline building electrical distribution system will be designed to meet Chapter 8 of ASHRAE Std for a feeder maximum voltage drop of 2% and a branch circuit maximum voltage drop of 3%. LEED NC version 3.0 Compliance The baseline building interior lighting power densities for compliance with Senate Bill 668 will use 1.0 watts/sf as permitted by ASHRAE Standard , Table 9.5.1: Lighting Power Densities using the Building Area Method for the Health Care Clinic classification. The lighting system will consist of energy efficient T-5, T-8 and compact fluorescent lamp technologies with matching electronic ballasts. Fluorescent lamps will be Low-mercury or green fluorescent lamps and will have green markings to denote that they have passed the U.S. Federal EPA Toxicity Characteristic Leaching Procedure (TCLP). Automatic lighting controls shall be provided in areas by either occupancy sensors or a programmable relay based lighting control panel(s). Occupancy sensors will be utilized to provide automatic lighting shut-off in, exam rooms, classrooms, conference rooms, and break rooms as required by Chapter 9 of ASHRAE Standard In accordance with ASHRAE , Appendix G, lighting controls for the baseline design will not have to be modeled. All other interior spaces within the building will be connected to the lighting control panel to provide scheduled time-of-day automatic lighting shut-off with local override switches. Dimming system controls will be utilized in spaces where applicable for the control of fluorescent lamps and for energy conservation. The baseline building exterior lighting system power densities will comply with ASHRAE Standard , Table 9.4.5: Lighting Power Densities for Building Exteriors and with Section for a minimum lamp efficacy of 60-lumens/watt. The baseline building electrical distribution system will be designed to meet Chapter 8 of ASHRAE Std for a feeder maximum voltage drop of 2% and a branch circuit maximum voltage drop of 3%. Page 5 of 6

6 Proposed Building Systems For the proposed building the interior lighting system will be comprised of high-efficiency fluorescent fixtures and will not exceed 0.95 watts/sf. Occupancy sensors will control the lighting in all spaces except corridors, lobbies, and mechanical rooms. The lighting control for these spaces will be provided by a programmable relay based lighting control panel to automatically control the lighting fixtures using a time-of-day scheduling matrix. Wherever feasible, exam rooms, offices, classrooms, and labs will be provided with a fluorescent dimming system that is controlled locally. Additionally, LED lighting sources will be explored for cost effectiveness. Additional energy savings will be achieved by reducing the power density for the exterior lighting system to less than the maximum power allowance permitted in Table in ASHRAE Std A target of 70-80% below that of the base building design will be the goal of this design. Sub-metering of new mechanical and new lighting systems will be provided for validating the actual energy used versus the energy model results and assumptions. Lighting systems located in areas incorporating daylight harvesting will be metered separately from all other sub-metered systems to allow for the verification of the effectiveness of the daylight harvesting design. System Alternatives: Daylight Harvesting: Areas of the building will be analyzed for daylight harvesting applications. This will be a working collaboration between the Architect and the Engineer. Automatic lighting controls will be developed based upon the Daylighting Study. Task Based Lighting: The reduction of the general ambient lighting levels for open office areas by using local task lighting in each area will be examined to determine the validity and costbenefit. Solar Powered Site Lighting: The use of solar powered pole-mounted site lighting fixtures will be analyzed for cost effectiveness. Page 6 of 6