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Leadership in Energy & Environmental Design. HVAC Focus. Buildings Consume 40% of the US Energy Supply. Building HVAC uses 25% of our electricity in the Southeast. What is LEED ® ?. “Leadership in Energy and Environmental Design” A voluntary rating system for sustainable buildings
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Leadership in Energy & Environmental Design HVAC Focus
Buildings Consume 40% of the US Energy Supply Building HVAC uses 25% of our electricity in the Southeast
What is LEED®? • “Leadership in Energy and Environmental Design” • A voluntary rating system for sustainable buildings • Launched by the U.S. Green Building Council in 2000 (www.usgbc.org) • Public demonstration of commitment • The standard measurement for high performance buildings
Project Checklist – New Construction & Major Renovations Version 2.2 (Possible Points) • Sustainable Sites 14 • Water Efficiency 5 • Energy & Atmosphere 17 • Materials & Resources 13 • Indoor Environmental Quality 15 • Innovation & Design Process 5 Project Totals 69
LEED® - NC Ratings? Documented achievement of prerequisites (7) & credits: Certified:26-32 credits Silver:33-38 credits Gold:39-51 credits Platinum:52-69 credits
Benefits of Building “Green” • Reduced Operating Costs • Reduced Waste • Reduced Environmental Impact • Reduced Potential Liability • Improved Indoor Air Quality • Increased Occupant Satisfaction • Increased Productivity • Enhanced Community Perception • Increased Market Demand/Building Value
Steps to LEED Certification Register Your Project Track Progress & Document Achievement Apply for Certification
Energy & Atmosphere (EA) Credits 17 Point(s) • Fundamental Commissioning of the Building Energy Systems Required • Minimum Energy Performance Required • Fundamental Refrigerant Management Required • Optimize Energy Performance 1-10 • On-Site Renewable Energy 1-3 • Enhanced Commissioning 1 • Enhanced Refrigerant Management • Measurement & Verification 1 1 • Green Power 1
Indoor Environmental Quality (EQ) Credit 15 Point(s) • Minimum IAQ Performance Required • Environmental Tobacco Smoke (ETS) Control Required • Outdoor Air Delivery Monitoring • Increased Ventilation 1 1 • Construction IAQ Management Plan 1-2 • Low-Emitting Materials 1-4 • Indoor Chemical & Pollutant Source Control 1 • Controllability of Systems • Thermal Comfort • Daylighting and Views 1-2 1-2 1-2
Innovation & Design (ID) Credit 5 Point(s) • LEED Innovation Credits 1-4 • LEED Accredited Professional 1
Sustainable Design Experience HDR ranks among the top companies nationally in total square footage of LEED® Certified and Registered projects. The collective area of all projects is 10,198,718 square feet (SF). The types of projects are diverse, from traditional office buildings to healthcare facilities and transportation facilities to laboratories. As of May 2008, the following HDR projects successfully earned LEED Certified or Registered status.
Air Conditioning & Refrigeration • 2 – 3: Refrigerant gas is compressed by compressor • 4 – 5: Hot gas flows through condenser (loses heat) and changes to liquid • 6 – 7: Liquid flows through the expansion valve – evaporates and changes to gas form again • 7 – 1: Gas flows through the evaporator to remove heat from air stream • Process starts again
Small A/C & Heat Pump Efficiency • Example: Heat removed = 6 ton/hr x 12,000 btu/ton = 72,000 btu/hr. Power used = 5,500 watts x 3.413 btu/hr/watt = 18,755 btu/hr • COP (Coefficient of Performance) = 72,000 btu/hr / 18,755 btu/hr = 3.84 • EER (Energy Efficiency Rating) = 72,000 btu/hr/5,500 watts = 13.1 • SEER (Seasonal Energy Efficiency Rating) is a better rating because it uses average values instead of values at any given point in the cycle • HSPF (Heating Season Performance factor) is the ratio of the seasonal heating output in Btu divided by the seasonal power consumption in watts. • Check ASHRAE 90.1 for latest minimum ratings HDR project - World Headquarters, Bio-Rad Laboratories Hercules, CA
Heat Pump - Cooling • Refrigerant gas is compressed by compressor • Hot gas flows through condenser (loses heat) and changes to liquid • Liquid flows through bypass and expansion valve – evaporates and changes to gas form again • Gas flows through the evaporator to remove heat from air stream • Process starts again
Heat Pump - Heating • Refrigerant gas is compressed by compressor • Hot gas flows through condenser (evaporator) and changes to liquid • Liquid flows through bypass and expansion valve – evaporates and changes to gas form again • Gas flows through the evaporator (condenser) to remove heat from air stream • Process starts again
Split-System Units • Inside air handler contains expansion valve, evaporator coil, air distribution fan and furnace or electric duct heater • Outside condenser contains a compressor, condensing coil and air fan • liquid refrigerant flows to evaporator and suction line gas flows to compressor/ condenser
Important HVAC References • ASHRAE Standard 90.1 – 2007 Energy Standard for Buildings Except Low-rise Residential Buildings (supersedes 90.1-2004) Appendix D – Building performance rating method • ASHRAE Standard 55-2004 Thermal Environmental Conditions For Human Occupancy Method for calculating acceptable thermal comfort ranges • ASHRAE Standard 62.1-2007 Ventilation for Acceptable Indoor Air Quality (Supersedes 62.1-2004) See Section 6.11 Ventilation Rate Procedure – Based on space type/application, occupancy level and floor area • ASHRAE Handbooks – Fundamentals, Refrigeration, HVAC Applications and HVAC Systems and Equipment • ASHRAE Green Guide – The Design, Construction and Operation of Sustainable Buildings