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Energy Efficient Glazing – FG0005
AIA CES Master – Energy Efficient Glazing FG005
PPG Industries Inc. is a Registered Provider with The
American Institute of Architects Continuing Education
Systems. Credit earned on completion of this program will be
reported to CES Records for AIA members. Certificate of
Completion for non-AIA members are available on request.
This program is registered with the AIA/CES for continuing
professional education. As such, it does not include content
that may be deemed or construed to be an approval or
endorsement by the AIA of any material construction or any
method or manner of handling, using, distributing or dealing in
any material or product. Questions related to specific
materials, methods, and services will be addressed at the
conclusion of this presentation.
Copyright Materials
This presentation is protected by US and International copyright
laws. Reproduction, distribution, display and use of the
presentation without written permission of the speaker is
prohibited.
PPG Industries Inc. 2008
Learning Objectives
By the end of this presentation, you will
understand:
• How low-e coatings work
• The differences between “passive” and “solar control”
low-e coatings
• How the energy, environmental and economic benefits
of low-e glass have been quantified
• The energy impact of various low-e coated glass
through simulation modeling
PercentTransmittance
Wavelength (NM)
0
10
20
30
40
50
60
70
80
90
100
300 500 700 900 1100 1300 1500 1700 1900 2100
UV VISIBLE IR
UV3%
Visible44%
Infrared53%
Spectral distribution of solar energy
at the surface of the Earth
Solar Energy Spectrum
Energy Efficient Glazing
Energy Efficient Glazing
Benefits: Low infrared heat gain
High visible natural light transmittance
Less artificial lighting
Reduction of long wave heat gain/loss
Increased comfort/productivity
Results: Overall reduction in
energy usage
Energy Efficient Glazing
Energy Efficient Glazing
Passive Low-E (pyrolytic, hard coat and MSVD , soft coat)
Solar Control Low-E (mostly MSVD, soft coat)
Non Low-E Glass (coated for tints or reflectivity)
Types of Coated Glass
Energy Efficient Glazing
Passive Low-E: Pyrolytic Coating Process
Energy Efficient Glazing
The Float Glass Process
Energy Efficient Glazing
Passive Low-E: Pyrolytic Coating Process
Pyrolytic Coating (Chemical Vapor Deposition)
Chemically applied or sprayed on hot glass during
manufacturing process (on-line process)
Creates strong thermal bond
Energy Efficient Glazing
Passive Low-E: Pyrolytic Coating Process
Pyrolytic Coating (Chemical Vapor Deposition)
Hard coat
Very durable
Withstands processing
Long shelf life prior to fabrication
Energy Efficient Glazing
Solar Control Low-E: MSVD Coating Process
Energy Efficient Glazing
Solar Control Low-E: MSVD Coating Process
Magnetic Sputtered Vacuum Deposition (MSVD)
Off-line coating process
Coating applied at room temperature
Most solar control low-e glasses are “soft coat”
Must be sealed in IG or laminated unit
Superior solar control performance
Low-E Coatings Role in
Energy Efficient Glazing
Visible Light Transmittance (VLT)
Low-E Coatings Role in
Energy Efficient Glazing
Solar Heat Gain Coefficient (SHGC)
Low-E Coatings Role in
Energy Efficient Glazing
Light to Solar Gain (LSG) Ratio:VLT ÷ SHGC = LSG
Low-E Coatings Role in
Energy Efficient Glazing
Winter Nighttime U-Value
Low-E Coatings Role in
Energy Efficient Glazing
Summer Daytime U-Value
Low-E Coatings Role in
Energy Efficient Glazing
DOE Funded LBNL Glazing Study On
“A well-proven window technology to reduce energy costs while
enhancing daylight and view.”
Spectrally Selective Glazings
Energy Efficient Glazing
“Spectrally Selective” vs. Moderate Glazing
Energy Efficient Glass Formula
“Spectrally Selective” = (LSG > 1.25) = Recommended
“Moderate” = (LSG < 1.25) = Not Recommended
Low-E Coatings Role in
Energy Efficient Glazing
“Spectrally Selective” vs. Moderate GlazingLawrence Berkeley National Laboratories (LBNL)
Glass is Spectrally Selective when: VLT SHGC = Light to Solar Gain (LSG) > 1.25
Examples (Spectrally Selective Glass)
Triple-Silver Coated MSVD Coated Glass
64% (VLT) ÷ 0.27 (SHGC) = 2.37 (LSG)
Double-Silver Coated MSVD Glass
70% (VLT) ÷ 0.38 (SHGC) = 1.84 (LSG)
Spectrally Selective Tinted Glass60% (VLT) ÷ 0.40 (SHGC) = 1.50 (LSG)
Examples (Non-Spectrally Selective Glass)
Pyrolytic Low-E (Passive Low-E) Coated Glass74% (VLT) ÷ 0.62 (SHGC) = 1.19 (LSG)
Low-E Coatings Role in
Energy Efficient Glazing
Low-E Coatings Role in
Energy Efficient Glazing
Energy Efficient Glass Formula Spectrally selective glass – VLT SHGC 1.25 LSG
Greatest amount of natural light transmission
Solar heat gain limited
Less need for daytime electrical lighting, saving energy
PercentTransmittance
Wavelength (NM)
0
10
20
30
40
50
60
70
80
90
100
300 500 700 900 1100 1300 1500 1700 1900 2100
UV VISIBLE IR
UV3%
VISIBLE44%
INFRARED53%
Spectral distribution of solar energy
at the surface of the Earth
Solar Energy
Spectrum
Wavelength (NM)
0
10
20
30
40
50
60
70
80
90
100
300 500 700 900 1100 1300 1500 1700 1900 2100
UV VISIBLE IR
PercentTransmittance
Ideal Glass
Solar Energy Transmittance
Emerald Green
Light Green
Blue/Green
Aqua Blue/Aqua Green
Spectrally Selective Tinted
Glazing
Solar Energy Transmittance
Wavelength (NM)
0
10
20
30
40
50
60
70
80
90
100
300 500 700 900 1100 1300 1500 1700 1900 2100
UV VISIBLE IR
PercentTransmittance
Medium Gray
Gray
Bronze
Dark Gray
Darker Gray
“Moderate” Bronze/Gray Glazing
Ideal
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance Criteria for Glazing
Glass Winter
U-Value
VLT SHGC LSG Ratio
Pyrolytic Low-E on Coated
Clear (Passive Low-E)
0.35 74% 0.62 1.19
MSVD Double- Silver
Coated
(Solar Control Low-E)
0.29 70% 0.38 1.84
MSVD Triple-Silver Coated
(Next-Gen Solar Control Low-E)
0.28 64% 0.27 2.37
Spectrally Selective Tinted
Glass
0.47 69% 0.49 1.41
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance Criteria
Glass Type Winter
U-Value
VLT SHGC LSG
Uncoated Glasses
Clear Glass 0.47 79% 0.70 1.13
Ultra-Clear Glass (Low-iron glass) 0.47 84% 0.82 1.02
Blue/Green (Spectrally Selective) Tinted
Glass
0.47 69% 0.49 1.41
Coated Glasses
Pyrolytic Low-E (Passive Low-E) Glass 0.35 74% 0.62 1.19
Triple Silver Solar Control Low-E 0.28 64% 0.27 2.37
Tinted Solar Control Low-E 0.29 51% 0.31 1.64
Subtly Reflective Tinted 0.47 47% 0.34 1.39
Blue/Green Reflective Tinted 0.48 27% 0.31 0.87
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance
Cradle to Cradle Certification, MBDC
The U.S. Green Building Council
Promote energy efficiency and sustainable design
LEED (Leadership in Energy and Environmental Design) program
LEED credits influenced by glass selection
Energy and Atmosphere (Energy Savings)
Materials and Resources (Recyclability)
Indoor Environmental Quality (Daylighting)
Cradle to Cradle™ Certification
In commercial buildings, up to 30% of electricity is used for interior
lighting.
Industry Background
0 5 10 15 20 25 30 35 40 45 50
Misc.
Refrigeration & Cooking
Water
Exterior Light
Office Equipment
Interior Light
HVAC
Percentage of Electricity Used
Estimated Electricity Usage in Commercial Buildings
Low-E Coatings Role in
Energy Efficient Glazing
• Most buildings in the country are not clad with the most efficient
glass available.
• There are approximately 77.2 billion square feet of built environment in the U.S.
• This figure is expected to climb by another 7 billion square feet (an additional 536,000 buildings) in the next five years.
• If this new development incorporates the most efficient glass technology available, significant upfront and long-term savings will result.
Low-E Coatings Role in
Energy Efficient Glazing
• If all existing buildings and new construction were to use the latest
glazing advancement – triple-silver Low-E glass – 2,134 trillion
BTU’s would be saved annually.
– This is 2% of the total US energy consumption
per year.
– This would save $38 Billion (gas and electric)
per year.
– CO2 emissions would be reduced by 123
million tons/year.
While that is the best-case scenario, the impact triple-silver Low-E
glass can have on energy consumption, economic savings and the
environment is vast.
Low-E Coatings Role in
Energy Efficient Glazing
Low-E Coatings Role in
Energy Efficient Glazing
Performance glazings can significantly affect the
heating, lighting, and cooling costs of a building
Daylighting and Energy Savings
Average savings 44%
$200 per employee
Average savings 52%
$68 per employee
Low-E Coatings Role in
Energy Efficient Glazing
Natural light has been shown to be psychologically beneficial, the
more light, the better
Recent studies link natural light with improved work environments
and increased productivity
Average savings 5.5%
$2,475 per employee
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance
Energy Modeling Real World Energy Savings
Real World Equipment Savings
Real World CO2 Emissions
Energy Simulations DOE 2.2 Building Energy Analysis Simulation
Developed by Lawrence Berkeley and Los Alamos National Labs
Hour-by-Hour Energy Consumption for One Year (8,760 hours)
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance
Energy Modeling
Two Major Building Types
Single-Story Middle School
Eight-Story Office Building
12 North American Cities
Five High-Performance Glazing Types
Window Walls or Punch Windows
Six Glazing Types
New, Triple-Silver MSVD Solar Control Low-E
Two, Double-Silver MSVD Solar Control Low-E
One, Pyrolytic Passive Low-E
One, (standard) Dual-Pane, Spectrally Selective Tint
Low-E Coatings Role in
Energy Efficient Glazing
Low-E Coatings Role in
Energy Efficient Glazing
270,000 square-foot, eight-story
office building
Punched window
Total window area: 33,418 ft2
Total wall area: 56,640 ft2
Window to wall ratio: 59% glass
Window wall
Total window area: 50,976 ft2
Total wall area: 56,640 ft2
Window to wall ratio: 90% glass
200,000 square-foot, one-story
school
Punched window
Total window area:18,863 ft2
Total wall area: 63,520 ft2
Window to wall ratio: 30% glass
Window wall
Total window area: 45,027 ft2
Total wall area: 63,520 ft2
Window to wall ratio: 71% glass
Low-E Coatings Role in
Energy Efficient Glazing
Office HVAC equipment
• VAV
• Centrifugal chiller
• Hot water boilers
School HVAC equipment
• Packaged VAV
• DX coils
• Hot water heating
• Gas water heater
Low-E Coatings Role in
Energy Efficient Glazing
Office internal peak loads
• Square ft/occupant: 448
• Lighting: W/sq.ft.: 1.3
• Equipment: W/sq.ft: 0.75
School internal peak loads
• Square ft/occupant: 123
• Lighting: W/sq.ft.: 1.1
• Equipment: W/sq.ft: 0.45
• Total Electric Consumption (kWh)
• Total Natural Gas Consumption (therms)
• Peak Cooling Load (tons)
• Peak Heating Loads (kBtu/hr)
• Total Supply Airflow (cfm)
• Total Electric Cost ($)
• Total Natural Gas Cost ($)
• Total Building Energy Consumption Cost ($)
• Cooling Equipment Capital Cost ($)
• HVAC Equipment Capital Cost ($)
• Total Cooling HVAC Capital Cost ($)
Low-E Coatings Role in
Energy Efficient Glazing
The Variables
• Atlanta
• Boston
• Chicago
• Denver
Low-E Coatings Role in
Energy Efficient Glazing
Mexico City
Ottawa
Philadelphia
Phoenix
Houston
Los Angeles
St. Louis
Seattle
• DOE 2.2
– Calculates hour-by-hour energy consumption of the prototype facility
over an entire year (8,760 hours)
– Uses hourly climate data for any location
– Detailed input provides accurate simulation of building features such as
shading, fenestration, interior building mass, envelope building mass,
and dynamic response of heating and air conditioning systems.
The Simulation Model
Low-E Coatings Role in
Energy Efficient Glazing
• DOE 2.2 energy simulations were developed for each glazing scenario
according to their unique characteristics
• The model ran a simulation for both building types, in all 12 locations, and
for both architectural scenarios (punched windows and window walls)
• The model calculated the effect of each glazing based on the following:
– Building loads
– Cooling equipment size
– Building energy costs
– HVAC Cooling costs
• based on cooling size in tons and total air supply flow into the
building
The Simulation Model
Low-E Coatings Role in
Energy Efficient Glazing
• Calculating HVAC capital cooling costs
– Calculations were based on peak cooling loads, in tons, for total air
supply into the building.
– Cooling costs were estimated at $1,200 per ton.
– HVAC equipment costs were estimated at $3.50 per cfm airflow.
• Utility rate calculations
– Utility companies for each of the 12 cities provided the latest rate tariffs
for electricity and natural gas.
The Simulation Model
Low-E Coatings Role in
Energy Efficient Glazing
• Calculating carbon emissions
– Derived using Carbon Dioxide Emissions for the Generation of Electric
Power in the United States, a report published in 2000 by the U.S.
Department of Energy.
*Estimates were used to simplify the model and meta calculations.
The Simulation Model
Low-E Coatings Role in
Energy Efficient Glazing
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance
Triple-Silver Coated MSVD vs. Dual Pane-Tinted Glass
City Annual HVAC Operating
Expenses
Annual
Savings
Total HVAC Equipment Costs Immediate
Equipment
Savings
1st Year
Savings
Dual-Pane
Tinted
Triple Silver Dual-Pane
Tinted
Triple Silver
Atlanta $680,456 $597,772 $82,684 $2,115,464 $1,697,686 $417,597 $500,281
Boston $853,450 $756,001 $97,539 $2,326,967 $1,928,086 $398,881 $496,420
Based on eight-story glass-walled office building
Total Glass Area: 50,967 ft2
Total Floor Area: 270,000 ft2
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance
Double-Silver Coated Tinted MSVD vs. Dual Pane-Tinted
GlassCity Annual HVAC Operating
Expenses
Annual
Savings
Total HVAC Equipment Costs Immediate
Equipment
Savings
1st Year
Savings
Dual-Pane
Tinted
Triple
Silver
Dual-Pane
Tinted
Triple Silver
Atlanta $681,456 $610,900 $70,556 $2,115,464 $1,772,350 $343,114 $413,680
Boston $853,540 $770,241 $83,299 $2,326,967 $2,003,328 $323,639 $406,938
Based on eight-story glass-walled office building
Total Glass Area: 50,967 ft2
Total Floor Area: 270,000 ft2
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance: CO2 reductions
Triple-Silver Coated MSVD vs. Dual Pane-Tinted Glass
Based on eight-story glass-walled office building
Total Glass Area: 50,967 ft2
Total Floor Area: 270,000 ft2
City Electricity
(KwH Savings)
Gas
(Therm
Savings)
Annual CO2
Reductions
(Tons)
40-Year CO2
Reductions
(Tons)
Acres of Pine
Forest Preserved
Atlanta 455,841 18,829 417 16,699 124
Boston 432,301 26,618 354 14,163 105
Chicago 434,777 29,644 502 20,087 149
Houston 473,971 14,199 422 16,889 126
Phoenix 469,246 6,170 411 16,451 122
Seattle 328,567 29,588 250 10,018 74
Low-E Coatings Role in
Energy Efficient Glazing
Energy and Environmental Performance: CO2 reductions
Double-Silver Tinted MSVD vs. Dual Pane-Tinted Glass
Based on eight-story glass-walled office building
Total Glass Area: 50,967 ft2
Total Floor Area: 270,000 ft2
City Electricity
(KwH Savings)
Gas
(Therm
Savings)
Annual CO2
Reductions
(Tons)
40-Year CO2
Reductions
(Tons)
Acres of Pine
Forest Preserved
Atlanta 377,043 17,176 353 14,138 105
Boston 356,143 24,455 306 12,220 91
Chicago 360,903 27,073 431 17,227 128
Houston 390,425 12,516 352 14,093 105
Phoenix 387,284 5,708 343 13,713 102
Seattle 271,799 26,627 219 8,670 64
Low-E Coatings Role in
Energy Efficient Glazing2nd vs. 3rd Surface
“The general recommendation from the glass industry for commercial buildings is to leave the choice (coating on either #2 or #3 surface) to the glass manufacturer.”(Source: MasterSpec Evaluation Section, Coated Glass.)
“For most commercial buildings, regardless of climate, in which the primary concern is reducing the solar heat gain, the location (coated surface) is of less concern, and placing it on either the second or third surface should remain an option.”
Low-E Coatings Role in
Energy Efficient Glazing
2nd vs. 3rd Surface
Coatings can be applied to the #2 or #3 surface of an insulating glass unit (IGU)
Having the flexibility to coat either the #2 or # 3 surface of an IGU allows for more competitive pricing without dramatically impacting its solar control performance
In some cases, (such as a tinted outdoor lite and a clear indoor lite) applying coatings to the #3 surface instead of the #2 surface permits accelerated product delivery
Learning ObjectivesThis concludes the continuing education portion of the course.
Here is a quick review of the learning objectives.
• How low-e coatings work
• The differences between “passive” and “solar control” low-e coatings
• How the energy, environmental and economic benefits of low-e glass
are quantified
• The energy impact of various low-e coated glass through simulation
modeling
PPG is an industry leader in manufacturing architectural glass, metal coatings
and paint and was the first to provide triple-silver MSVD solar-control Low-E
glass. For more information on the study and its results you can contact PPG
by visiting www.ppgideascapes.com or by calling 1-888-ppg-idea (774-4332).
Thank You
Close/Conclusion
This concludes The American Institute of Architects Continuing
Education Systems Program
Questions?
Thank you for your time.
PPG Industries
• PPG is a global supplier of paints, coatings, optical products, specialty materials, glass and fiber glass
• PPG has manufacturing facilities in 23 countries. The company has operations and equity affiliates in more than 60 countries
• PPG generated revenues of $11.2 billion and invested more than $330 million in research & development
Australia • Argentina • Belgium •
Brazil • Canada • China • England
• France • Germany
Ireland • Italy • Japan • Mexico •
Netherlands • Philippines • South
Korea • Spain
Taiwan • Thailand • Turkey •
United States • Venezuela
Glass
– Worlds Leader in Production of Commercial, Military and General Aviation Glass
Fiberglass
– Electronic Circuit Boards, Recreational Boat Hulls, Tub and Shower Units.
Chemicals
– Pharmaceutical, Agricultural, Plastics, Water Purification, Pulp/paper Manufacturing, Oil Drilling, Aluminum Production
Plastic Photo Chromic Lenses – Transitions
Transportation Coatings
– World’s Number 1 Producer of Transportation Coatings.
– Two of Every Three New Cars on the Road Today in North America Contain PPG Coatings
Industrial Coatings
– Agricultural and Construction Equipment, Automotive Parts and Accessories, Appliance, Coil, Aluminum Extrusion, Wood Flooring, Recreation and Others
Packaging Coatings
– Beverage Can Linings, Packaging Inks
Products
PPG Low-E and
Solar Control Low-E Glasses
Triple-Silver MSVD Coated Solarban® 70XL Solar Control Low-E Glass
Next-generation Solar Control Low-E Glass
Clear glass appearance
Can be combined with tints for enhanced performance
2006 Architectural Record “Green Product of the Year”
Shades of Green Award, Green Building Alliance
LSG of 2.37, highest in the industry
All PPG glasses are Cradle to Cradle Certified
PPG Low-E and
Solar Control Low-E Glasses
Double-Silver MSVD Coated Solarban® 60 Solar Control Low-E Glasses
Clear glass appearance
Can be combined with tints for enhanced performance
LSG ratio of 1.84 combined with clear glass in a 1” IGU
All PPG glasses are Cradle to Cradle Certified
PPG Low-E and
Solar Control Low-E Glasses
Double-Silver MSVD Coated Solarban® 80 Solar Control Low-E Glasses
Steel jade exterior appearance
LSG ratio of 1.96 combined with clear glass in a 1” IGU
Can be combined with Optiblue glass
Solarban® z50 Solar Control Low-E Glasses
Variety of tints: steel blue-gray to aqua blue
LSG ratios of up to 1.64
30% better performance than competitive products
Low interior reflectance
Clear, natural outdoor views
Optiblue glass is available only with select Solarban
products through PPG Certified Fabricators.
All PPG glasses are Cradle to Cradle Certified
PPG Low-E and
Solar Control Low-E Glasses
Pyrolitic Low-E Glass (Passive Low-E) Sungate® 500 Passive Low-E Glass
Clear glass appearance
Almost two decades of proven performance
More than 200 million square feet shipped in last decade
LSG of 1.19 with clear glass in a 1” IGU*
Can be combined with tints for LSG ratios of up to 1.66
* Without tints, this glass does not meet the U.S. DOE criteria for spectrally selectivity
All PPG glasses are Cradle to Cradle Certified
PPG Low-E and
Solar Control Low-E Glasses
Spectrally Selective Tinted Glasses Oceans of Color™ Spectrally Selective Glass
Atlantica™ Glass (1.50 LSG ratio)
Azuria™ Glass (1.56 LSG ratio)
Caribia® Glass (1.55 LSG ratio)
Solexia™ Glass (1.41 LSG ratio)
Vistacool® Subtly Reflective, Color-Enriched Glasses
Vistacool Azuria (1.61 LSG ratio)
Vistacool Caribia (1.66 LSG ratio)
Vistacool Solargray (1.13 LSG ratio)*
* This glass does not meet the U.S. DOE criteria for spectrally selectivity
All PPG glasses are Cradle to Cradle Certified
PPG Low-E and
Solar Control Low-E Glasses
PPG High-Performance Tinted Glass PPG Performance Tinted
Optigray® 23 Glass
Graylite® Glass
Solarbronze® Glass
Solargray ® Glass
Solarcool ® Reflective Tinted Glasses
All PPG glasses are Cradle to Cradle Certified
• Technical & Product Hotline: 888-PPG-IDEA (774-4332)
• Direct technical support
• Sourcing Assistance
PPG’s reliable network of applicators, contractors and
certified fabricators
The Right Information, Right Away
• All PPG architectural products
• MSDS sheets and technical data
• Download product literature
• Order samples 24/7
• Order literature 24/7
• Read case studies
• Visit photo galleries
The Right Information, Right Away
• Solarban® Solar Control Low-E Glasses
• Sungate® Passive Low-E Glass
• Starphire® Highly-Transmittive Glass
• Oceans of Color™ Spectrally Selective Tinted Glasses
• Vistacool® Subtly Reflective Color Enriched Glass
• Duranar® Fluoropolymer Coatings
• Duranar® ULTRA-Cool® Fluoropolymer Coatings
• Duranar® VARI-CoolTM Fluoropolymer Coatings
• Superl® II ULTRA-Cool® Siliconized Polyester Coatings
• Pittsburgh® Paints Zero-VOC Pure Performance Paint
• Speedhide®, Manor Hall® & Porter® Paints
• MegaSeal® Flooring Systems
A portfolio of proven products to help architects achieve sustainable design
goals.
Environmental LeadershipPPG is committed to environmental sustainability
Our glass and coatings are used in the production of wind and solar power,
and we do extensive research and development to make these technologies
more commercially viable
PPG helped automakers eliminate lead from primer coatings, purge chrome
from rinses, cut VOC emissions, stifle the corrosion of metal, and save energy
by lowering curing temperatures for automotive paints and coatings.
We actively manage our own manufacturing processes to improve air
quality, and reduce water and energy consumption
Corporate Goals:
Reduce energy use by 25% by 2016
Reduce green house gas emissions by 10%