California’s Commercial Building
Energy Asset Rating System (BEARS)
April 8th 2013
Acknowledgements
2
An Energy Asset Rating…
…evaluates the energy efficiency potential of a
building
3
3
An Energy Asset Rating…
…evaluates the energy efficiency potential of a
building based on its construction, installed
energy-consuming systems, and renewable
energy systems.
4
4
An Energy Asset Rating…
…evaluates the energy efficiency potential of a
building based on its construction, installed
energy-consuming systems, and renewable
energy systems. Energy asset rating should
not be considered an estimate of a building’s
actual energy use
5
5
An Energy Asset Rating…
…evaluates the energy efficiency potential of a
building based on its construction, installed
energy-consuming systems, and renewable
energy systems. Energy asset rating should
not be considered an estimate of a building’s
actual energy use, rather it is designed to give
the owner an idea of the energy efficiency
potential of the building independent of the
way the building is currently operated.
6
6
An Energy Asset Rating…
…evaluates the energy efficiency potential of a
building based on its construction, installed
energy-consuming systems, and renewable
energy systems. Energy asset rating should
not be considered an estimate of a building’s
actual energy use, rather it is designed to give
the owner an idea of the energy efficiency
potential of the building independent of the
way the building is currently operated. This
perspective enables a reasonable comparison
of a building’s energy efficiency potential to
other buildings.
7
7
Which is Getting Better MPG?
~20 MPG
http://www.curbsideclassic.com/autobiography/the-great-american-anti-towingconspiracy/
8
~100 MPG
http://tourismplacesworld.blogspot.com/201
1/08/worlds-steepest-street.html
Which is More Efficient?
50 MPG
50 MPG
http://blacktagdiaries.blogspot.com/2010/06/sad-day-forprius.html
9
20
20 MPG
MPG
http://tourismplacesworld.blogspot.com/2011/08/worldssteepest-street.html
Role of an Asset Rating
•
Real estate transactions
•
Inform policy goals
•
Demonstrate benefits of
energy efficiency
•
Prioritize energy efficiency
investments
10
BEARS Rating Process
Data Collection
Data Analysis
Rating
Calculation
Rating
Communication
11 11
Data Collection
12
Sensitivity Analysis
13 13
Input Parameter
Equipment Power Density
Lighting Power Density
Cooling Efficiency
Window Area with Daylight Control
Roof Reflectivity
Glazing (solar heat gain coefficient)
Daylight Controls
HVAC System Type
Fan Static Pressure
Window Area with no Daylight Control
Infiltration
Roof Insulation
Glazing U-Value
Domestic Water Heating Efficiency
Wall Insulation
Heating Efficiency
Ventilation Airflow
Electric
49.37%
21.74%
11.51%
5.50%
5.47%
5.23%
4.92%
3.73%
3.49%
3.44%
0.96%
0.74%
0.57%
0.00%
0.35%
0.03%
0.00%
Gas
1.46%
0.23%
0.00%
0.00%
0.06%
0.18%
0.06%
0.23%
0.06%
0.00%
0.23%
0.12%
0.06%
42.69%
0.06%
0.06%
0.00%
Data Collection Considerations
Sensitive Parameters
14 14
Non-Sensitive Parameters
Energy Modeling
15
DOE Reference Buildings
•
•
•
•
16
EnergyPlus
ASHRAE 90.1 and 62.1
16 building types
Represents 70% of the commercial building
stock
http://apps1.eere.energy.gov/buildings/energyplus/openstudio.cfm
Building Types
17
Proposed BEARS
Building Types
DOE Reference
Building Available
Large Office
Medium Office
Small Office
Data Processing/Computer Center
Lab/R&D Facility
Quick Service Restaurant
Full Service Restaurant
Bar/Tavern/Nightclub/Similar
Supermarket
Convenience Store
Stand-alone Retail
Strip Mall
Refrigerated Warehouse
Unconditioned Warehouse
Conditioned Warehouse
Small Hotel
Large Hotel
Primary School
Secondary School
College or University
Religious Assembly
Health/Fitness Center
Theater/Performing Arts
Library/Museum
Conference/Convention Center
Other Recreational/Public Assembly
Service
Assembly/Light Mfg.
Police/Fire Stations
x
x
x
Modify DOE
Reference Building
New Modeling
Protocols Required
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Data Translation
Data Collection Field
Data Collection
Parameter
EnergyPlus
Translation
Occupancy Type
Medium Office
Schedule = M-F 7:007:00, Occupancy
Density, Ventilation
Rate
Vintage
1995
Default constructions
and efficiency values to
Title 24 requirements in
place in 1995
Interior Lighting Power
Controls
Occupancy Sensors
Apply power factor
adjustment based on
assumed space type
Field Surveys
19
Data Collection Testing
•
20
5 sites
• Café
• Two Office Buildings
• Quickserve Restaurant
• Grocery Store
BEARS Rating
21
BEARS Certificate
Future of BEARS
23
Future of BEARS
•
•
•
•
•
24
Testing
Refine framework
Develop assessor training
Develop BEARS software tool
Grow scope to include more buildings
BEARS provides a new way of
thinking about the value of a
building’s permanent assets, and
creates a more robust link between
energy efficiency and property
value
Kevin Campbell
kcampbell@peci.org
503-575-4169
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