Facades+ PERFORMANCE
San Francisco
11 July 2013
Measured Building Energy Performance: First Results from the NY Times HQ Building Stephen Selkowitz, Eleanor Lee Windows and Building Envelope Materials Building Technology and Urban Systems Dept Lawrence Berkeley National Laboratory seselkowitz@lbl.gov
Lawrence Berkeley National Laboratory
The Vision
• “Net Zero Energy Buildings” is the right goal • NZEB = 60-80% savings + renewables
• Just Do It The Dream
– Set a goal - march toward it – Its easy, if we commit and apply ourselves – We have the technology and know-how
• Major National Challenge
The Reality
age 2
– Technically attainable - Difficult to achieve in scale – Shortcomings: Owners? Users? Tools? Construction? Operations? – Integrated Standards -Deployment-DemonstrationResearch – Issues- Policy, Finance, Design Process, Technology
1976 Perspective: Code Official s View of the Ideal Windows
Lawrence Berkeley National Laboratory
$(! 0 " " % / " "' % ' & Dependent on a number of parameters •  •  •  •  •  •  •  • 
Climate Orientation Building Type Fenestration area Glass type Operations Daylight Shadin
Slopes vary depending on efficiency of lighting and HVAC systems Energy Use
Increased lighting energy use and gains
Increased solar heat gains
Need to balance a number of issues •  •  •  •  •  •  •  • 
Energy Demand Carbon Peak Cooling Comfort: visual/thermal View Appearance ‌‌
Minimum energy use • 
Ideal: Integrated approach to façade-lighting-HVAC building systems to achieve optimum energyefficiency and comfort.
‌ Its moderately Complicated!! Lawrence Berkeley National Laboratory
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Lawrence Berkeley National Laboratory
3 Pathways for Use of Glass in Commercial Buildings • “Just meet the code" – Small Windows, prescriptive properties, e.g. double – No special shading or daylighting
• Mainstream good solutions: (prescriptive packages) – – – – –
Moderate sized windows, skylights Double glazing Spectrally selective glass Manually operated Interior shading On-off lighting controls
• Architectural Solution: Transparent Façade – – – – – –
Highly glazed façade; extended daylighted zone Reliable tools reduce risk High Performance technology with Systems Integration Dynamic, smart control- automated shading, dimmable lights Economic from Life cycle perspective Optimized for people and for energy, electric demand Lawrence Berkeley National Laboratory
Reality: How Do Buildings Really Perform?: Design Simulation vs Measured Performance Observations: 1. Various building types, ages, locations 2. Average over all projects is not bad 3. Max over-predict by 120% 4. Max under-predict by 65% 5. Almost all under-predicted for low energy designs (red triangle: EUI <= 40) 6. Uncalibrated simulated results
Measured EUI (kBtu/ft2)
Measured=Design
Design EUI (kBtu/ft2) Source: Energy performance of LEED-NC buildings, NBI, 2008
New Performance Data: 1. NYC Disclosure data 2. California 3. 5 other cities; more coming
Lawrence Berkeley National Laboratory
Quantifying and Exposing Performance:
Disclosure Legislation As of 6/2013: • 19 States • 16 Cities
Implications: - Access to Data - Owner’s Awareness - Bridges Design to Operations - Increased Concern leading to action - Guilting to Action Source: http://www.buildingrating.org/ammap
Lawrence Berkeley National Laboratory
Performance in the Real World Matters! Learning from Field Measurements
Lawrence Berkeley National Laboratory
Advanced Facades and Daylighting Program Goals: Net Zero Energy Balance for New and Retrofit Enhanced View and Thermal Comfort Reliable, cost effective operations Tools to design, optimize, specify, control Adoption/diffusion throughout industry
Advanced Technologies:
Sensors; Controls; Hi R windows, Cool coatings; Switchable coatings; Automated Shading; Daylight-redirecting Operable windows,
Human Factors: Thermal comfort Visual comfort Satisfaction Performance
Application: All climates All Building types New-Replacement-Retrofit
Program Activities: Simulation Optimization Lab test Field Test Demonstrations Standards
Partners Manufacturers Owners Architects Business Case Decision Tool Engineers Manufacturing Books, Guides Specifiers Installation Websites Code officials Commissioning Simulation Tools Contractors Reliability keley National Laboratory Labora att Utilities a Testbeds Cost Lawrence Berkeley
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Lawrence Berkeley National Laboratory
Full-Scale Test Bed Built into Oakland GSA Federal Building, 1990- 1992 • • • • •
Side-by-side test offices; occupancy effects (interior changes only) Owner engagement Stage 1: Unshaded large-area electrochromic windows Stage 2: Automated interior blinds with optimal controls Integrated controls optimize energy and demand for window and lighting system
Lawrence Berkeley National Laboratory
Test Bed -> Pilot Demonstration: Emerging Integrated Systems
• Electrochromic Windows – Automated control – Manual override
• Lighting Controls – DALI dimmable ballasts – Architectural scenes, occupancy, daylight controls
Lawrence Berkeley National Laboratory
LBNL Advanced Façade Testbed Facility
2003-2006 Electrochromic windows 2007-2013 Automated Shading Industry Advisory Groups: Manufacturers Glazing, Shading Framing, Lighting Controls
Designers Architects, Engineers Specifiers
Owner/Operators Public, Private
Utilities
• Berkeley, South facing 3 Rooms • Changeable façade • Lighting, HVAC • Heavily instrumented • Static/Dynamic • Occupant Studies • Controls/Automation Lawrence Berkeley National Laboratory
Exploring Performance of Integrated Shading and Lighting Controls in LBNL Facade Testbed Facility Daylight Redirecting Glass
Electrochromic Glass External Dynamic Shading Lawrence Berkeley National Laboratory
Automated daylight blind: concave-up slats with mirrored coating in upper zone and light grey finish in lower zone
Lawrence Berkeley National Laboratory
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4
2
1
5
3
2
6
3
Lawrence Berkeley National Laboratory
Average Annual Lighting Energy Use vs Visual Discomfort
10% of day = 1.2 hours
Percent of day window > 2000 cd/sqm
full power ref-RS
0.57 W/sf 0.34 W/sf
auto-RS
LPD (W/sf)
split-VB auto-VB diff-VB split-opt-VB ref-VB auto-split-mir-VB1
0.31 W/sf 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Berkeley National Laboratory Conclusion: Automated systems Lawrence deliver excellent energy savings and comfort
Gathering In-Situ Occupant Data on Daylight/ Shading from Desktop Polling Station
Source: K Konis
Lawrence Berkeley National Laboratory
(Day)Lighting Control Elements
ballast controller ballast lamp sensor Electric Light Selec + Sdaylt Task View Daylight Ambient Illum Illum Lawrence Berkeley National Laboratory
Good Lighting Controls (Daylight Dimming) Work Daily Energy Use (6 A.M to 6 P.M.) kWh/12 hr/zone
40 G
South Daylit
J
North Daylit
Reference
H
35 30 25 20 15 10 5
HH H H H H H H H H H H HH H H H HH H H H H H HH H H HH H H HH H H H HH H H H HH H H H HH H HH H H HHH H H HH H H H H H HH HH H H H H HH HH H HH H H H H H HH H H H H HH HH H H H H HH H H H H HH H H H H H HH H H HH HH HH HH H H H H H H HH H H H H H H H H HH H H H HH H H H H H H H HH H HH H HH HH H H H H H H H H H H H H HH H H H H H H HH H H HHH H H H H H H H H H H H H H H H H H H H H H H H H H H HH H H H H HH HH H H H HHH H HH H HH H HHHH H HH HH H
40-60% Savings
40-80% SavingsG
G GGG G G G J GGG G GG GGG GG G G G JG G G G G G G G G G JG GGG G JJ GG GGG J GJ GG GGGG G G G GG G G J JG J JJG G G JJJJJJG G G G JG J JJJJJG G G G G G G G JJJJJJG JJG G G G G G G G G J G G G J G G G G G GGGJ G G G G G G G G G G G G J G G G G J J G G G G G G G G GG GGG GGGG J JG JGJG GGG G G G J G G G G G G G G G G J G G J GG JJ J JJJJJJJJ J J G G GG G G GG GG GG GG G G G GG GG GGG G JG GGGGGG GG G JJJJJ JJJJJJJJJJJJJJGJJ H G JG GGGG G GG G GG GG G G G JJJJJ J G GG GG GG G G J JJJJJJJ J JJ G G G G G G G J G G G G J G G G G G J G G J G G GG G G G G GG G G G G G GG JJJJJ G G J JJJJ JJJ G JJJJJ JJ J JJ JJJJJJJJJ J JJ J JJJ JJJJJJJJJ JJJ J JJJ JJJ JJ JJ J J JJJJJJJJ JJJ JJJ J J J JJJJJJJJJ JJJJJJJJJJJJ JJ JJJJ G J J J J J J J J J J J J J J J G J J J J G JJ J J J J JJ J JJJJJJJJ JJ JG J G JG J J JJ
0 0
50
H
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100
150
200
Day of Year 1990
H
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250
300
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350
Data from advanced lighting controls demonstration in Emeryville, CA (1990) !!! Energy Use before retrofit: After retrofit: South zone: North zone:
But Dimming is only 3% of lighting sales!
Lawrence Berkeley National Laboratory
Exploring Intelligent Control Systems: Maximum performance requires full integration with all building systems (manual control??) Task Requirements
Dynamic Window (active control of daylight, glare, solar gain)
User Preferences Interior Conditions
Smart Controllers
Lighting Systems (with dimming ballasts, sensors)
Weather Conditions Load Shedding/ Demand Limiting Signal Sensors, meters,â&#x20AC;Ś
Energy Information System
Building Performance (cost, comfort, operations)
Lawrence Berkeley National Laboratory
H V A C
Integrated Systems Performance: Design Operations Need Better Models/Data to Quantify Investment Tradeoffs:
Office Eq.
Heating
Cooling
Lighting
$
$
First Cost
Annual Cost
$
= First Cost
Loads Systems Supply
$
Peak Cooling Load
Chiller Size
Lighting Design Strategy
Energy, Peak Electric Demand
$
$ $
Cost Lawrence Berkeley e keley National N=a Annual Laboratory
$ Onsite Power Generation Central Power Generation
$
Annual Energy Costs in Perspective Cost / Sq. Ft. Floor -Year • • • • •
Energy Cost: Maintenance: Taxes: Rent: “Productivity”
$2.00 $3.00 $3.00 $30.00 $300.00+
Lawrence Berkeley National Laboratory
The Bottom Line at The New York Times Building • The building was designed to save energy as well as satisfy occupants • Shading systems and lighting control systems were rigorously developed and evaluated in a full scale testbed • Owners engaged key systems suppliers via performance specs • Procurement/installation process was designed to minimize cost • Proper installation and operation was verified pre-occupancy • Owner engaged occupants in the overall process • 2013: Over ~ 5 years, the systems (dimming, shading, UFAD) worked well; Compared to a similar Code-compliant building:
– 56% lighting energy savings – 24% total energy savings – 21-25% reduction in summer peak demand – Economic Paybacks appear very reasonable – Overall Occupant Satisfaction is high; some areas need refinement Lawrence Berkeley National Laboratory
Façade Performance in The NY Times Buildings • Background to the Times Building Project • Overview of the DOE Post Occupancy Study – Field Measurements – Calibrated Simulation Models – Occupant Feedback • Lighting and Daylighting – Shading – UFAD and HVAC • Overall Energy/Peak • Unique to the Times Building vs. Replicable? • Lessons Learned – Next Steps Lawrence Berkeley National Laboratory
New Reports and Websites http://windows.lbl.gov/comm_perf/newyorktimes.htm
Download the Report
Lawrence Berkeley National Laboratory
New York Times Building: 2003-> 2013 • 2002 Building Design • 2003- 2007: Planning, Mockup Testing, Procurement, Installation, Commissioning • 2007: Occupancy • 2011-2012: Post Occupancy Evaluation Study – NY Times Occupant Survey (NYSERDA) – Post Occupancy Energy Evaluation (DOE, CEC)
• •
Date: Tue, 21 Jan 2003 05:48:38 -0800 David A Thurm/NYT/NYTIMES wrote:
• • • • •
Anticipating our visit next Wednesday, I'm sending you a "care package" that includes a description of our new building, the detailed lighting study done by our lighting consultant and some details of the curtain wall The annexed link is to photos of a model of the building: http://www.nytimes.com/partners/.
•
• • • • • • • • • • • • • • •
As it stands now, our line-up of participants is: The New York Times Company Michael Golden, Vice-Chairman David Thurm, VP Real Estate Development Hussain Ali-Khan, Exec. Dir. Real Estate Glenn Hughes, Dir. Construction Angelo Salvatore, Dir. Finance Susan Brady Lighting Consultants Susan Brady Flack & Kurtz (MEP engineers) Fred Holdorf, VP electrical Genlser (interior architects) Ed Wood (Lead designer on our project) -------------------------------------------------------------------------David
Lawrence Berkeley National Laboratory
2003-2005: Physical & Virtual Testing
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Physical • Evaluate Shading, daylighting, employee feedback and constructability in a ~450 M2 testbed
2
• Fully instrumented; 1 year testing Virtual • Shade Control Algorithms for Motorized Shades Developed using Simulation • Built a virtual model of the building in its urban context using hourly weather data simulate performance
17
2
18
17
18
Simulated Views from 3 of 22 view positions
Lawrence Berkeley National Laboratory
N A B
Full-Scale Mockup
North
College Point, Queens
A B
• Field study provided sufficient information about the risks and rewards of daylighting • 4500 ft2 southwest corner of a typical floor • Real sun and sky conditions in nearby climate zone • 6-month monitored period: winter to summer solstice + 3 more months to study alternative shading control options • Technologies: – Daylighting controls – Automated roller shades • Investigate diverse technological solutions by multiple vendors (this is NOT a side-by-side comparison) Lawrence Berkeley National Laboratory
Lawrence Berkeley National Laboratory Interior View: South-west corner zones
Daily Lighting Energy Savings vs Distance from Window (Averaged data: Corner window zone) • Daily lighting energy savings – 47 ± 19% avg savings in zone 10 ft from west window – 76 ± 16% avg savings in zone 10 ft from south window – 42 ± 18% and 37 ± 20% in zones 15 ft and 25 ft from the south and west windows – Compared to base case with no daylighting controls Daily = sun up to sun down
Lawrence Berkeley National Laboratory
Radiance model: floor plan view
Lawrence Berkeley National Laboratory Radiance Model of Typical Floorplate
Radiance modeling: building geometry in Manhattan Digital model
Lawrence Berkeley National Laboratory
Urban context
NYT site Lawrence Berkeley National Laboratory Radiance Model inserted at Site Location
Illuminance studies
Radiance Results Plotted on Typical Floorplate: Animations over typical days
Dec 21 10:00 Lawrence Berkeley National Laboratory
Dec 21 12:00
Assessing Glare and Lighting Quality: Luminance measurements at typical Workstations
1:3
1:3 remote
1:3 remote 1:3
1:3
1:3 1:3
1:3
Lawrence Berkeley National Laboratory
Background
VDT Visibility in the Mockup Vs Time of Day, Shade Position
10/26/04
3:40 pm
Task 5:00 pm Lawrence Berkeley National Laboratory
Radiance Model: Assessing Glare vs Orientation, Shade position, Floor Level.
Lawrence Berkeley National Laboratory
Solar Exposure: West faรงade Hours of Sunshine vs Floor Level and Orientation
Lawrence Berkeley National Laboratory
Probability Blinds are Closed
Occupant Studies in Testbed Identify When to (automatically) Close the Blindsâ&#x20AC;Ś.
Window Luminance (cd/m2) Lawrence Berkeley National Laboratory
Glare Assessment vs Shade Operating Strategy West facade Floor 6
Floor 26
Lawrence Berkeley National Laboratory
Each Green and Blue Dot is an office location with Time Lapse Radiance Simulation conducted at that workstation Available at LBNL website Lawrence Berkeley National Laboratory
Floor 26
Floor 6
Images from Time Lapse:Lawrence WinterBerkeley Solstice; AM Laboratory â&#x20AC;&#x201C; Noon - PM National
Floor 26
Floor 6
Images from Time Lapse: Equinox; AMNational â&#x20AC;&#x201C; Noon - PM Lawrence Berkeley Laboratory
And More…. • Procurement Specifications: download from website
• Field Verification of Prototypes in Mockup • Field Calibration Tools for Owner to verify installed performance of Lighting and Shading systems Lawrence Berkeley National Laboratory
Occupied 2007 Lawrence Berkeley National Laboratory
2011- 2012: (Day)Lighting Results • Building Features that Promote Daylight Savings: – Large daylight aperture with external fixed shading – “Reverse” floorplan: individual offices moved to the core – Cruciform floorplate allows greater daylight access – State-of-the-art automated lighting and shading controls – Furniture systems with low partition heights • Prior LBNL mock-up study showed potential lighting energy savings of 10-60% savings to ~ 20 ft from the windows • Lighting control system records “ballast control voltage” continuously; convert to “lighting power” with measured data • Shading system tracks and archives “shade position” • Assess Occupant Satisfaction to Daylighted Environment – A. Hinge Lawrence Berkeley National Laboratory
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Lighting control system (LCS) subdivides floor into zones • Lighting control subdivides by zones
Open Office N1
• Daylighting dimming is independently done in smaller subzones
Open Office N1
Open Office N2
Open Office N2
Open Office W1
Open Office E5
Open Office W2
Open Office E4
Open Office W3
Open Office E3
Open Office W4
Open Office E2
Open Office W5
Open Office E1 Open Office S1
Open Office S1
49
Open Office S2
Open Office S2
Lawrence Berkeley National Laboratory
Typical day of LCS zone data
“All lights on” power level
• Zone W3, 20th floor, May 12 2001 • (Spikes were spurious and disregarded in the analysis) Lawrence Berkeley National Laboratory
50
Lighting Control Strategies • Scheduling – Set to Nominal Work Hours – Set in advance, “on-off”, floor • Occupancy – are there people in the space? – Dynamic, “on-off”, local/addressable • Tuning – set the lighting setpoint to the desired level – Set in advance, “dimming”, local/addressable • Daylight – dim electric light by fraction of daylight provided – Dynamic, “dimming”, local/addressable
Lawrence Berkeley National Laboratory
51
Challenge: How to Allocate Savings Between Different Control Strategies Net Lighting Energy Consumption Over 1 Day
Lawrence Berkeley National Laboratory
Dimming (for daylight and tuning) provides 53 significant savings, adds to occupancy and scheduling Open Office E1 Open Office E2 Open Office E3 Open Office E4 Open Office E5 Open Office N1 Open Office N2 Open Office S1 Open Office S2 Open Office W1 Open Office W2 Open Office W3 Open Office W4 Open Office W5 All daylit zones 0
2
4
6
8
10
Energy density (kWh/ft2.yr) Energy consumption after savings
Daylighting/tuning savings
Occupancy savings
Scheduling savings
20th Floor zones
Lawrence Berkeley National Laboratory
12
Lighting Energy Savings: Savings (Absolute and %) Depend on Base Case No controls (a)
11.4
Scheduling (b)
7.09
Scheduling + occupancy (c)
Use
5.11
Setpoint tuning + daylighting dimming (d)
3.15
Savings compared to no controls (a-d)
8.25
Savings Savings due to dimming controls (c-d)
1.96
0
2
4
6
8
10
12
Annual lighting energy use (kWh/ft2-yr)
Lawrence Berkeley National Laboratory
his view: ata Set: U.S. National (CBECS) ocation: Us Census= New England, Middle Atlantic, East orth Central, West North Central, South Atlantic, East South entral, West South Central, Mountain, Pacific ize: 100,001 to 200,000 sq ft, 200,001 to 500,000 sq ft, 00,001 to 1 million sq ft, Over 1 million sq ft intage: 1990 to 1999, 2000 to 2003 ype: Administrative/professional office, Bank/other financial, overnment office, Medical office (non-diagnostic), Mixed-use ffice, Other office
+ setpoint tuning and daylighting: 3.15 kWh/ft2-yr
lights on 365/24/7: 11.55 kWh/ft2-yr
+ occupancy/scheduling: 5.08 kWh/ft2-yr
CBECS - US
How Much Energy Do We Use to Light Buildings? (large office) Times Building vs National/California Data This view: Data Set: California only (CEUS) Location: California= Central Coast, Central Valley, Desert, Mountains, North Coast, South Coast, South Inland Size: Over 150,000 sf Vintage: 1991 through Present Type: Administration and Management, Assorted/Multitenant, Financial/Legal, Government Services, Insurance/ Real Estate, Medical/Dental Office, Other Office, Software Development
CEUS - CA
Lawrence Berkeleyy National Laboratory Laborattory
Less than 3 year payback achievable at lower end of installed cost range Estimated Added Cost for Dimming/Daylight
Payback time (yrs)
12
10
8
Occupancy +dimming Dimming only
6
4
2
0 0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Installed cost ($/ft2) Lawrence Berkeley National Laboratory
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Economic Analysis of Dimmable Lighting Controls Depends on Utility Rates
Notes: Incremental installed cost $2.12/ft2 for a 30x40 ft perimeter zone, 30 year life, discount rate 6%. Flat rate: $0.19/kWh; TOU: Category 9, Rate II. HVAC energy use reductions due to reduced heat gains from lighting and potential HVAC capacity reductions were not included in this analysis. The net present value is the net profit and does not include the cost of the initial investment. *Cost of conserved energy should be less than or equal to the local utility rate (i.e., $0.19/kWh).
Lawrence Berkeley National Laboratory
NY Times Perspective on Dimming Ballasts: ~200558 (Dimming Ballasts will Fall to Much Lower Price Points with Larger Markets) $/ballast
Price analysis 100 First look was terrifying 80 After Lightfair 2004… challenging 60 With the mock up… encouraging 40 Post mock up… economic viability!! 20
Initial estimates
Static Electronic Ballast
Pre-bid estimates
Bid results
0 Lawrence Berkeley National Laboratory
Target
Occupant Satisfaction is High: Quality of Light, Visual Comfort In terms of the overall quality of light in your workpace, are you: Very satisfied
31% 29% 18% 12%
Neutral 6% 3% 2%
Very dissatisfied 0%
5%
10%
15%
20%
25%
30%
35%
40%
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Lawrence Berkeley National Laboratory
Control Logic: Automated Shading and Dimmable Lighting Tuning Setpoints, Occupancy sensing, Overrides Load Shed Demand Response
Smart Controller
Lighting Controls (daylight sensor)
User Preferences Override Local Window Luminance Global Solar Conditions Load Shedding/ Demand Limiting Signal
Smart Controller
Dynamic Shading, Glare Control (active control of daylight, glare, solar gain)
Building Performance (cost, comfort, operations)
Sensors, meters,â&#x20AC;Ś
Lawrence Berkeley National Laboratory
H V A C
Automated Shading: Manages Glare, Reduces Cooling Load
Lawrence Berkeley National Laboratory
Direct Measurement of Daylighting and HVAC Faรงade Impacts is Complex
For Times Study a hybrid approach using measured field data and simulation was used to estimate overall energy use
Interior and Exterior Automated and Manual Shading and Daylighting Under Test at LBNL today.
Lawrence Berkeley National Laboratory
Fixed External Shading and Solar Control: Modeling in EnergyPlus to Assess Energy Impacts
Notes: • Complex façade with fixed external and variable internal shading • Transmitted solar energy can strike floor or furniture- different impacts • Extensive Radiance modeling to track absorbed solar Lawrence Berkeley National Laboratory
Occupant Response to Automated Shading Reduce sunlight
42%
Maximize view
25%
Too warm
15%
Other
11%
Decrease privacy
4%
Adjust brightness
2% 0%
10%
20%
30%
40%
50%
Override data: Answers to “Why did you change shade position?” Observations: • “You can’t please all the people all the time….” • Open office environments mixes people and locations; human variability • New construction on Northwest corner of site – recalibration to exterior site • Time Clock calibration issues Lawrence Berkeley National Laboratory
Underfloor Air Distribution (UFAD)
Observations: • l: - Sophisticated systems hidden below • r: - wireless sensor grid deployed to measure underfloor and stratified temperatures, humidity and flows • Measured input to calibrated EnergyPlus model Lawrence Berkeley National Laboratory
EnergyPlus: Peak Summer Cooling Demand Simulation: ASHRAE 90.1 vs Times Overall Peak Electric Demand: 21-25% reduction; Lighting and Cooling
Lawrence Berkeley National Laboratory
24% Reduction in Energy Use: Times Building vs ASHRAE 90.1-2001
• Simulation with Calibrated Model • Notes: Site Energy Use- Times vs 90.1-2001 • Many assumptions….. Documented in report • Electric measured “directly” • HVAC modeled with calibrated zonal temperature and flow data, and measured shade position • Caution: No elevators, exterior lighting, kitchen,… Lawrence Berkeley National Laboratory
How Can We Scale This? • Times Building Data Confirms the Opportunity and Challenges – Potential savings are substantial – Falling systems costs and rising energy/demand cost
• Conclusions; We Need: – Facades with Integrated glazing and shading - Attention to glare control and solar control
– – – –
Integrated dimmable lighting system Design process follow-through to Occupancy Contractor and Supplier Engagement Occupant engagement
• Crawl….. Walk……Run…… – Monitored demonstrations; Extend NYC “disclosure” for systems level ? – Build market pull around high volume, lower cost packages – 1 Building 1 City Engage nationally to leverage effort Lawrence Berkeley National Laboratory
68
NY Times “Mockup in a Box”??
69
Goal: A toolkit to: 1. Accurately Predict (and Optimize) Energy Performance of Any Façade System 2. “Value Engineer”, Construct and Commission to meet Design Goals 3. Operate to Continuously Achieve Energy Performance and Occupant Satisfaction Goals
Software; Testbeds Lawrence Berkeley National Laboratory
Glazing and Faรงade Decision-Support Tools 70 Download http://windows.lbl.gov/software/ 2012 ~ 40,000 Downloads
THERM
Optics
IGDB
Angular SHGC/U/VT
(Window Glass)
(Specular Glass Data Source)
(Window Frame)
(Rating/Lableling)
CGDB (Complex Glazing Data Base)
WINDOW +
Shading Systems (Whole Window)
EnergyStar Ratings
Radiance Lighting /Daylighting
COMFEN (Whole Building Commercial)
RESFEN (Whole Building Residential)
Commercial Windows Website Efficient Windows Website Berkeley National Laboratory DesignLawrence /Simulation Tools
Process for Determining Optical Properties of 71 Honeycomb Shades
Measure Coupon of Fabric
Construct Material Properties File
=
Using Fabric Properties Perform Ray-Tracing in WINDOW and Construct Cellular Shade BSDF Lawrence Berkeley National Laboratory
Nominal Tv = .74 (NFRC value, normal incidence) Hourly Monthly Transmittance (WINDOW7)
72
Latitude 38 Vertical glass South facing
View location dependent annual transmittance for an optical system Lawrence Berkeley National Laboratory
Radiance visualization in WINDOW
73
Tvis What does the space look like? Lawrence Berkeley National Laboratory
COMFEN: Façade Early Design Tool Download: windows.lbl.gov/software - Early Design Tool for Façade Systems: Thermal and Daylighting Impacts - A tool to Optimize Energy Use, Carbon, Comfort…
Lawrence Berkeley National Laboratory
74
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75
FLEXLAB: 76 Facility for Low Energy EXperiments in Buildings 4 Outdoor Testbeds: 3 1-story 1â&#x20AC;Ż 2-story 3 Indoor Testbeds Lighting/Plug Load Sensors/Controls Design Lab Data Acquisition, Monitoring, Control System
Lawrence Berkeley National Laboratory Laborratory 76
Under Construction â&#x20AC;Ś. 77
Lawrence Berkeley National Laboratory 77
Reconfigurable, “Kit-of-Parts” Interchangeable lighting and controls
Interchangeable façade elements: shading, glazing
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Interchangeable skylights
Interchangeable HVAC systems: air- and waterbased
Data acquisition and controls
Lawrence Berkeley National Laboratory
7 78
Field Performance of Integrated Systems • FLEXLAB provides proof of concept, reduces risk for early adopters • FLEXLAB accelerates the deployment curve
R&D Concept, Theory
Early Adopters Real Buildings
Lab Scale Test Beds
FLEXLAB R&D Program
Validated Tools
Scalable Deployment
FLEXLAB Deployment Focus
Federal, Utilities State, Local Government Industry Partnership Program
Building Owners
Architects & Engineers
Manufacturers
Investors & Entrepreneurs
79
Lawrence L awrence Berkeley Berkele eyy National National Laboratory Laboratory
Measuring Performance… • Continue Movement to Design in Virtual World – More Economical, Powerful Tools on the way… – Address most aspects of “performance” – Validate Tools with Measured Data • Set Design Expectations …. And Deliver Performance – Building ratings, disclosure laws “Guarantee”?? – Static Dynamic Performance • New Business Models – Collaboration Risk but Opportunity – Shift from “payback” to broader “value proposition” • Field Test Data Critical to Building the Performance Case – Net Zero Facades Outperform Insulating Walls… Lawrence Berkeley National Laboratory
80
Challenge and Opportunities for “Net Zero Energy Facades” • Make high performance and energy efficiency a market advantage, not an extra cost or a risk • Must Deliver Measured Savings! • New Technology, Smarter Design offers: – New Business Opportunities – Design freedom and flexibility – Value-added benefits, e.g. better acoustics – New performance benefits: e.g. comfort – Modest/no extra first costs and large annual savings – Lower impact on global environment
81
Manufacturer Architect Occupant Owner Society
Lawrence Berkeley National Laboratory
Information Resources Stephen Selkowitz SESelkowitz@lbl.gov More Info: New York Times project http://windows.lbl.gov/comm_perf/newyorktimes.htm Access to 60 Downloads
*$577- " #-&6 6 #,7% &#+% &7 % &#+% &6$ Advanced Facades project http:lowenergyfacades.lbl.gov http://gaia.lbl.gov/hpbf Commercial Web Site http://www.commercialwindows.org
http://buildings.lbl.gov
Lawrence Berkeley National Laboratory
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