Tech Session from the 2009 ASHRAE Region VI CRC in Des Moines, Iowa. Presented by Paul Torcellini of NREL May 8, 2009

1. NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC
ASHRAE Region VI CRC
Paul A. Torcellini,
Ph.D., PE
May 8, 2009
www.highperformancebuildings.gov
Tech Session 4: Benchmarking/
Performance Measuring

2. National Renewable Energy Laboratory Innovation for Our Energy Future
Case Study Buildings
– Oberlin College Lewis Center
• Oberlin, Ohio
• goal: zero net site energy use (79%)
– Zion Visitor Center
• Springdale, UT
• goal: 70% energy cost savings (65%)
– Cambria Office Building
• Ebensburg, PA
• goal: 66% energy cost savings (43%)
– Chesapeake Bay Foundation (CBF)
• Annapolis, MD
• goal: LEED 1.0 Platinum Rating (25%)
– Thermal Test Facility (TTF)
• Golden, CO
• goal: 70% energy savings (51%)
– BigHorn Home Improvement
• Silverthorne, CO
• goal: 60% energy cost savings (53%)
– Science House, Science Museum of Minnesota
• St. Paul, Minnesota
• goal: zero net site energy use (139%)

3. Different Metrics-Different Results
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Oberlin BigHorn TTF Cambria Zion CBF
PercentSavings
Percent Net SourceEnergy Savings
Percent Net SiteEnergy Savings
Percent SiteEnergy Savings
Percent Energy Cost Savings
measureddatavs. simulatedbasecasesimulatedas-built vs. simulatedbasecase

4. BigHorn Home Improvement Center
18,400 sqft retail store and 24,000 sqft
warehouse
Daylighting
Natural ventilation (no mechanical cooling)
Radiant floors
Transpired solar collector
PV

5. Ventilation PreheatVentilation Preheat
Over 70% efficientOver 70% efficient
Acts as a building skinActs as a building skin
11¢¢/kWh heat production/kWh heat production
Transpired Solar CollectorTranspired Solar Collector

6. Electric Lighting and DaylightingElectric Lighting and Daylighting

7. Daylighting System PerformanceDaylighting System Performance
savings: daylighting = 65%; overall = 79%
0
1000
2000
3000
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7000
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9000
10000
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Month
EnergyConsumption(kWh)
0
10
20
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PercentReductionfrom
Daylighting
No Daylighting
Daylighting
% savings

8. Zion Visitor Center
7.2 kW PV system (UPS)7.2 kW PV system (UPS)
Passive evaporative coolingPassive evaporative cooling
Excellent thermal envelopeExcellent thermal envelope
TrombeTrombe wallswalls
OverhangsOverhangs
DaylightingDaylighting

9. Zion Visitor Center
Daylighting
Operable Windows
Overhangs

10. Downdraft Evaporative Cooltower
Cool Air
Hot Air

11. Trombe Wall
Heating
Radiant Ceiling Panels

12. Cooltowers

14. HVAC System
Envelope is integral to the heating and cooling system
– Cooltowers and Trombe wall
– Natural ventilation
Ceiling fans
Bathroom/office exhaust fans
No ductwork
Electric radiant heat (propane expensive)
Demand responsive EMS
No fuel storage or mechanical rooms

15. PV System
7.2 kW (24 300-W modules)
2 single phase
inverters
(one with UPS)
PV can meet loads of
phone, security, POS,
and cooltowers (UPS
battery backup)
Grid power out 40 times
during monitoring year.
PV provides about 8%
of annual total.

16. Other Features
Extensive daylighting
Good thermal envelope
Trombe wall heating
Overhangs
PV can meet loads of
phone, security, POS,
and cooltowers (UPS
battery backup)
Grid power out 40 times during monitoring year.
PV provides about 8% of annual total.
70% energy savings (measured)

17. Peak Demand
Plot of 15-minute data showing demand responsive controls
-5
0
5
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40
0:00
1:00
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22:00
23:00
EndUse,Purchased,andPVProduction(kW)
Net Used
Total PV
Total HVAC
Total Equipment
Total Lighting
Hot Water Heaters

18. Measured Energy Performance
$0.43/year to operate (including plug loads)
27.0 kBtu/ft2/year (including plug loads, but no PV)
7,860 kWh produced by PV or 8% of total (24.7 kBtu/
ft2/year net)
Visitor Center Heating
Fee Station
Ceiling and Exhaust Fans
Comfort Station Cooling
Comfort Station Plug Loads
Visitor Center Domestic Hot
Water Comfort Station Domestic
Hot Water
Visitor Center Plug Loads
Outdoor
Comfort Station Visitor Center Switch
Controlled
Visitor Center Computer
Controlled
Visitor Center Cooling
Comfort Station Heating
Equipment/
Other
33%
HVAC
36%
Lighting
31%

19. Lewis Center for Environmental Studies
13,600 sqft classroom and offices
60 kW PV system on roof
Daylighting
Ground-source Heat Pumps
Water Treatment
Natural Ventilation

21. National Renewable Energy Laboratory Innovation for Our Energy Future
Oberlin Lewis Center Monthly Energy Performance
January 2000 - December 2002
0
200
400
600
800
1000
1200
1400
1600
Jan-00
Feb-00
Mar-00
Apr-00
May-00
Jun-00
Jul-00
Aug-00
Sep-00
Oct-00
Nov-00
Dec-00
Jan-01
Feb-01
Mar-01
Apr-01
May-01
Jun-01
Jul-01
Aug-01
Sep-01
Oct-01
Nov-01
Dec-01
Jan-02
Feb-02
Mar-02
Apr-02
May-02
Jun-02
Jul-02
Aug-02
Sep-02
Oct-02
Nov-02
Dec-02
DailyAverageMonthlyConsumptionandProduction
(kWh/day)
Utility Bills
Equipment
Total Lights
Total Cooling
Total Heating
PV Production
The Value of Monitoring

22. Receptacles
Emergency receptacles
PV system consumption
DHW
Auditorium lights
Indoor room lights
Hydronic circulation pumps 3-6
VSD Hydronic circulation
pumps 1-2
Room Heat Pumps
Classroom energy recovery
unit
Auditorium energy recovery
unit
Emergency lights
Sidewalk lights
Parking lot lights
Classroom ventilation heat
pump
Auditorium heat pump
Hydronic system electric boiler
Wastewater treatment
Elevator
Total
Equipment
28%
Total Lights
13%
Total HVAC
59%
End Loads

23. National Renewable Energy Laboratory Innovation for Our Energy Future
NREL Thermal Test Facility (TTF)
10,000 sqft Laboratory and Office
Typical steel frame building
Good insulation package
Simple daylighting design

24. National Renewable Energy Laboratory Innovation for Our Energy Future
Plug Loads
22.0%
Exterior
Lights
4.2%
Hot Water
1.1%
Heating
4.0%
Cooling
1.6%
Fans/Pumps
1.8%
Lighting
12.1%
Savings
52.9%
Plug Loads
22.0%
Exterior
Lights
4.2%
Hot Water
1.1%
Heating
2.7%
Cooling
8.3%
Fans/Pumps
4.6%
Lighting
57.0%
Loads Example
Code
Building
Final
Design
72% savings excluding plug loads and exterior lights

25. Available Roof Layouts

26. More Daylighting…

27. Education and
Marketing

28. Image…

29. High Performance Building’s Database
• Shared, on-line repository of in-depth
descriptions and data on high-performance
and green buildings
• Commercial, residential, campus
• Single database, multiple portals
• Examples of low-energy buildings to motivate
industry
• Mechanism for others to report on building
performance and lessons learned
http://www.eere.energy.gov/buildings/database/

30. Case Study Database Objectives
• Lack of comprehensive energy-based case
studies
• Provides feedback to both DOE and industry
– Industry needs proof that low-energy is possible
– DOE needs feedback to understand successes and failures
in real world examples
• Create a standardized reporting format for
building energy performance

31. Pages for
– Overview, Process, Finance, Land Use,
Site/Water, Energy, Materials, Indoor
Environment, Images, Ratings, Lessons
Learned, and Learn More

32. Features
Pages for
– Overview, Process, Finance, Land Use,
Site/Water, Energy, Materials, Indoor
Environment, Images, Ratings, Lessons
Learned, and Learn More

33. Energy Table Page
• Multiple energy tables
– Allows for comparisons/tracking
with time
• Basecase, simulated, utility data
(by year)
• Longer term reporting
• Narratives
• Data Sources and Reliability

34. Portals
– DOE High-Performance Buildings Database (101 projects)
– BuildingGreen, Inc. (230 projects)
– American Institute of Architects (92 projects)
• Top Ten Winners
– U.S. Green Building Council (108 projects)
• LEED Case Studies
– Federal Energy Management Program (44 projects)
• New Federal buildings must be entered by EPACT2005
– Efficiency Vermont (4 projects)
– Cascadia Chapter USGBC (35 projects)
– DOE Net Zero Energy Buildings (4 projects)
• Buildings that have measured performance of ZERO
– ASHRAE (5 projects)
• AEDG Case Studies
– DASH (New project)
• Focus on financial/real estate/productivity metrics
– International Energy Agency – Solar Heating and Cooling Programme Task 40
• International case studies for Zero and near Zero Commercial and Residential
Project (new as of 11/15/08)
– Massachusetts Technology Collaborative (20 projects)
– There are others…

35. Distribution of Projects
DASH

36. National Renewable Energy Laboratory Innovation for Our Energy Future
High-Performance Buildings Database
Share successes and lessons learned about
projects
Public database
Actual Energy Information
FEMP, USGBC, AIA, DOE all have “front
ends”
A special section for ZEB’s.
www.highperformancebuildings.gov

37. You can enter projects…
• Go to
www.highperformancebuildings.gov
– enter the database
– Create a login and submit a project

38. Lessons Learned from the HPBd
• Getting energy data is hard
– Even utility bills
– This is the part that viewers want to see the most
– This is one of the few real measures of success – it can be
measured and quantified
• The risk of sharing lessons learned
– Need to be willing to share mistakes
– Needed to advance the industry—or we will never get there.
• Transparency is key.

39. National Renewable Energy Laboratory Innovation for Our Energy Future

40. National Renewable Energy Laboratory Innovation for Our Energy Future
What are [Net] Zero Energy Buildings?
Conceptually, a building that has no adverse
energy [or environmental] impact [because of
its operation]
ZERO is not easy to define!
– Disconnect all utility interfaces?
– Net energy transfer across boundary?
– Where is the boundary?

41. National Renewable Energy Laboratory Innovation for Our Energy Future
Definitions of NZEB’s
Net Zero Site Energy
Net Zero Source Energy
Net Zero Emissions
Net Zero Energy Cost
Boundaries and metrics

42. National Renewable Energy Laboratory Innovation for Our Energy Future
Net Zero Site Energy
Measured at the interface of the building to the
utility (point of sale)
Easy to measure/verify (vested interest in
having the right number)
Can favor electricity over on-site combustion
Encourages energy efficient designs at the
building level
What is the “site?” Building footprint or property

43. National Renewable Energy Laboratory Innovation for Our Energy Future
Net Zero Source Energy
With current information, really
just site with multipliers for
different fuels
Has a grid (more global) impact
Depends on dispatch of power
generation
– Fuel source
– Incremental dispatch
Daily and seasonal dependencies
Regional (non climatic) dependencies
Not a strong focus on building efficiency

44. National Renewable Energy Laboratory Innovation for Our Energy Future
Net Zero Energy Cost
What the owner really sees
(Also) based on site measurements
Easy to verify
Demand component
High regional variations
Highly dependent on rate structures
(demand and fixed charges cannot
be negated)
Cost volatility
Market driven comparisons
Cannot do this on a large scale (Who would pay
the utility?)

45. National Renewable Energy Laboratory Innovation for Our Energy Future
Net Zero Emissions
Also based on site numbers, typically with
national or regional multipliers based on
generation location
Same issues as source
If a building has zero
source energy and
therefore zero
emissions, is it really a
zero emissions building?

46. National Renewable Energy Laboratory Innovation for Our Energy Future
Renewable Hierarchy
• Energy efficiency
• Renewable in/on building
• Renewable in/on property
• Import renewables
(wood chip, other biofuels)
• Purchase renewable credits

47. National Renewable Energy Laboratory Innovation for Our Energy Future
Ending Thoughts…
Zero takes a coordinated effort with the
architect and the engineering
The little things make the difference in getting to
zero (as you get to zero, little is significant)
The owner needs to set measurable goals and
communicate these goals to the design team
The solution is not bigger supplies

48. National Renewable Energy Laboratory Innovation for Our Energy Future
Questions?
www.highperformancebuildings.gov