Transcript Slide 1
Building Simulation
B M E A
uilding odeling nergy nalysis
What is BMEA?
Models a building Existing or proposed • • • • •
Shell and Core Lighting Equipment Load Occupancy Internal Mass
• • • •
Environmental Systems Schedules Climate Utility Service
Shell and Core
• • • • • • • • • •
Exterior walls Windows Doors Roof Shading Insulation Floors Ceiling Interior walls Interior mass Structure and finish Glass, frame, size Type and size Type, material, overhang Natural and structural Type and R-value Floor covering and insulation Construction and insulation Construction and arrangement Furniture
Lighting
• • •
Bulb Fixture Placement Recessed, surface, or hanging Open or enclosed
Equipment Load
• • •
Office Equipment Infrastructure Industrial Process Load Breakdown
• • •
Utility Thermostat Meter Total building load Loads in zones Loads in non-HVAC spaces
Environmental Systems
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Built-up
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Package
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Split system
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Air & water
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Geothermal
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Solar
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Process HVAC
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VFD Pumps and fans
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T-stat warm-up and setback
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Exhaust fans
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Zoning
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Domestic hot water
Schedules
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Daily, weekly, and annual
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Weekends and holidays
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Types
Occupancy Lighting Equipment Environmental Systems
Climate
• • • •
Model anywhere in the U.S.
Seasonal Day and night 30-year average
Utility Service
• • • • •
Electric and gas Anywhere in the U.S.
Basic and demand charges Block and ratchet charges Rate analysis
What can BMEA do for me?
Reduce energy costs
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Evaluate options
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Optimize strategies
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Compare costs
Simple payback Life cycle Return-on-investment •
Evaluate energy usage
Rate reductions Rebates Tax credits
Caveats
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Clearly defined objectives
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Cost-effective modifications
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Energy-usage figures are relative
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Cost vs. Value
Two-Story Office Building
Portland, OR
Structure -
25,000 sq. ft.
6” concrete slab Ext. Wall – 2 x 6 metal frame Fiberboard sheathing R-19 batt Built-up roof 3” polyurethane R-18
Two-Story
Office
Building Windows -
¼” Double-clear on North ¼” Double-bronze all other
Doors Int. Wall -
¼” clear glass w/ 3” Al frame 2” x 4” metal frame Drywall R-13 batt
Two-Story
Office
Building Ceiling -
Lay-in acoustic tile No ceiling insulation
Floors -
Carpet w/ fiber pad 12 foot floor-to-floor 9 foot floor-to-ceiling
Two-Story
Office
Building Lighting -
2 x 4 concealed troffer T8 ES fluorescent High-efficiency magnetic ballast
Loads -
2 watt/sq. ft.
No exterior loads
Two-Story
Office
Building Occupancy -
8 am – 5 pm Mon – Fri Major US holidays 90% while open
Two-Story
Office
Building Environmental Systems
AHU Supply and return fans Economizer Constant speed +1 hour open/close Chill water coil 55F discharge air for cooling
VAV
Two-Story
Office
Building
Core and perimeter zones 74 / 72 Occ. – 82 / 64 Unocc.
Plenum return Hot water heating coil 95F discharge air for heat
Two-Story
Office
Building Chiller -
Electric recip. hermetic Air-cooled condenser 44F supply water
Boiler -
Natural gas 80% efficiency rating 180F discharge water
Two-Story
Office
Building Domestic Hot Water
Natural gas 88-gallon tank 135F discharge
Pumps
Constant speed Standard motor
Two-Story
Office
Building Electricity Natural gas
PGE Schedule 32 Small Non-Residential 0.085/kW NW Natural Schedule 31 Non-Residential 0.95/Therm (100,000 Btu)
Running the Simulation
Baseline
Electricity 146,650 kW $12,465 Natural gas Energy Total 5,252 Therms $4,935 $17,400
Running the Simulation
Raise Cooling Set Point
Raise cooling set point from 74F to 75F Reduce annual electricity consumption 2250 kW annually $190 per year 1.1% of annual energy cost
Running the Simulation
Replacing the Boiler
Install 90% efficiency boiler Reduce natural gas consumption 550 Therms annually $525 per year 3.0% of annual energy cost Oregon Business Energy Tax Credit 35% of project cost over five years
Running the Simulation
Synergy
Raise the temperature and replace the boiler 2250kW 737 Therms $190 annually $695 annually $885 in energy savings 5.1% of total energy bill
Wrapping it Up B
uilding
M
odeling
E
nergy
A
nalysis • Simulate an existing or proposed building • Model a wide range of building elements Structural Environmental • Flexible and adaptable • Cost-effective analysis