Energy Savings Impacts of the Advanced Energy Design Guide: Small Office Buildings Bing Liu, P.E. Research Engineer Pacific Northwest National Laboratory Tel: (509) 375-3710 Bing.liu@pnl.gov Energy Use Simulation Approach Scoping Study: Baseline building – Standard 90.1-1999 Advanced building – Off-the-Shelf technology Two Models: 5,000 sf and 20,000 sf office buildings Use eQuest to test run in four climate locations: Miami, Phoenix, Seattle and Duluth Full Study: 15 representative locations in 8 DOE Climate Zones Use DOE-2.2 directly to make 60 parametric runs for full study February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 2 5,000 ft² Office Prototype Square floor plan Single story Frame construction 20% window-to-wall ratio Single tenant February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 3 20,000 ft² Office Prototype Square floor plan 2-story Masonry construction 30% windowto-wall ratio 3 tenants February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 4 What is in the Baseline Building? Comply with Standard 90.1-1999 Insulation requirements for roofs, walls, floors and slabs U-Value and SHGC for window glazing U-Value for doors Interior lighting power density Mechanical equipment efficiency Economizer requirement And more… February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 5 What is in the Baseline Building? When not specified by 90.1-1999… Room Thermostat: Setpoint: 75°F cooling & 70°F heating Setback/Setup: 80°F cooling & 65°F heating Office Equipment Plug Load Schedules Energy Policy Act Standard analysis Recent research study and peer review comments Fan Static Pressure February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 6 Plug Load Schedule - Weekday Fraction of Defined Peak Load 20,000 sf Office Building 1.0 0.8 0.6 0.4 0.2 0.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Hour of Day Before After ASHRAE SP102 Advanced Energy Design Guide Modeling Assumptions & Energy Usage - 20,000 sf Office Building Table 5 Baseline Modeling Assumptions (Round 2) – Seattle, WA Characteristic Architectural Features Configuration/Shape Aspect Ratio Zoning Number of Floors Window to Wall Ratio Floor-to-Ceiling Height: Floor-to-Floor Height: Infiltration Rate Infiltration Schedule Roof Structure Exterior Finish Insulation Overall U-factor Emissivity Solar Reflectance Baseline Model 1 5 zones per floor (one core + four perimeter zones) 2 30% ribbon windows uniformly distributed by orientation 9 ft 12 ft 0.038 cfm/sf of the gross exterior wall 0.122 air change per hour for entire building OFF_M-F_INFIL Steel deck with rigid insulation Single-ply roof membrane R-15 ci 0.063 0.87 0.23 (grey EPDM) Data Source SP 102 Recommendation General practice General practice ASHRAE 90.1-1989 §13.7.3.2 12 feet high Exterior Wall Off when the HVAC fan is on SP 102 Recommendation ASHRAE 90.1-1999 Table B-14 ASHRAE 90.1-1999 Table B-14 Grey single-ply membranes from PG&E High Albedo (Cool) Roofs CASE Study Report at http://www.newbuildings.org/downloads/co des/CoolRoof.pdf What is in the Advanced Building? Envelope Cool roofs Better insulations High performance windows and doors Overhangs for windows except facing north Interior Lighting Reduced installed lighting power density Daylighting harvest for WWR 25% or higher Daylighting dimming control on south and north perimeter zones Occupancy Sensor February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 9 What is in the Advanced Building? Mechanical System Higher efficiency unitary equipment in some climate zones Motorized outside air damper control Demand Control Ventilation (DCV) Lower duct friction rate: 0.08 in/100 ft vs. 0.10 in/100 ft of standard practice Service Water Heater Higher thermal efficiency for gas-fired storage water heater or Gas-fired instantaneous water heater February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 10 Energy Savings of Advanced vs. Base Building (Without Plug Load) 30% Goal Over Standard 90.1-1999 40% 30% 20% 10% 5000 sf Bldg 20,000 sf Bldg an ks h irb ul ut Fa D a el en H on gt rli n Bu hi ca g o e C is Sa Bo em p n Fr his an ci Al bu sco qu er q B a ue lti m or e Se at tle so M Pa ni x El oe Ph st on ou H ia m i 0% M Energy Savings, % 50% Energy Savings of Advanced vs. Base Building (Including Plug Load) Energy Savings, % 50% 40% 30% 20% 10% 0% i s a e n o e o e is le th r t m k on enix aso s c n u g o i h t t u t o a n s l i p o a le rq im ca ing u P ci us ho i e e B e M m ba l t n D o h l l r u S H i e r a E P H C u M Ba Fr lbuq Fa B n A a S 5000 sf Bldg 20,000 sf Bldg iam Base Case Advanced Case Fa irb an ks Du lu th rlin gt on He le na Ch i ca go Bu at tl e Bo ise Se Ph oe ni x El Pa so M em ph Sa is n Fr an ci s co Al bu qu er qu e Ba ltim or e i Ho us to n M EUI, kBtu/sf Energy Use Index 5,000 sf Office Building 120 100 80 60 40 20 0 iam i Ho us to Ph n oe ni x El Pa so M Sa em ph n is Fr an ci Al bu sco qu er q Ba u e ltim or e Se at tl e Bo is Ch e i ca go Bu rlin gt on He le na Du l Fa uth irb an ks M EUI, kBtu/sf Energy Use Index 20,000 sf Office Building 80 60 40 20 0 Base Case Advanced Case Comparison of Energy Savings Percentage Savings Over 90.1-1999 5,000 sf Office Building 60% Average Savings of All the Climate Zones = 38% 49.1% 50% 40% 35.6% 36.4% 30% 20% 10% 0% Miami Lighting Baltimore Cooling Heating Duluth Fans SWH Comparison of Energy Savings Percent Savings Over 90.1-1999 20,000 sf Office Building 50% 40% Average Savings of All the Climate Zones = 38% 38% 43% 35% 30% 20% 10% 0% Miami Lighting Baltimore Cooling Heating Duluth Fans SWH Advanced Simulation Challenges Real windows vs. DOE-2 window library Window Shading Coefficient Method Window Library Method Window Layers Method February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 17 Advanced Simulation Challenges Occupancy sensor DOE-2 doesn’t have occupancy sensor module Modify the lighting schedule to estimate the potential energy savings from the occupancy sensors February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 18 Lighting & Occupancy Sensor Schedule Fraction of Defined Peak 1.10 1.00 0.90 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 0.00 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Weekday - Hour of Day Lighting Lighting with Occupancy Sensor Advanced Simulation Challenges Demand ventilation control No CO2 sensor module in DOE-2 Modify the outside air change rate to reflect the average reduction of the outside intake using CO2 sensor – 20% February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 20 Advanced Simulation Challenges Motorized outside air damper control Potentially saving cooling and heating energy during nights by closing the OA damper when fans cycle on to maintain space setback temperature Hourly-based simulation may overestimate the energy savings from the motorized outside air damper in the cold climates February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 21 Questions? Bing Liu, P.E. Pacific Northwest National Laboratory Tel: (509) 375-3710 Bing.liu@pnl.gov February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla. 22