Advanced Glazing and Window Technologies

Brandon Tinianov, Ph.D., P.E., LEED AP

Chief Technology Off icerSerious Materials

Our Mission: to reduce carbon dioxide emissions by one billion tons annually

• Building Energy Consumption• 62% goes to light ing, plugs, equipment• 38% goes to goes to condit ioning (heating and

cooling)

• Residential heating: 6.2 Q BTU• Residential cooling: 2.5 Q BTU

• Commercial heating: 2.1 Q BTU• Commercial cooling: 1.6 Q BTU

Breakdow n of the Opportunity

• Much of the condit ioning consumption is due to loss through the building envelope.

• More heat is lost is lost through the building envelope than is generated by the heating systems, • Solar heat gain and internal loads from equipment add up to

50%

• Reducing the envelope heat loss by 29% can save 30% heating energy

• Up to 80% of res. and 40% of comm. loads are due to solar heat gain via roof and w indows

Breakdow n of the Opportunity

Alaska Pipeline Energy Goes “Out the Window”

Comparison courtesy Amory Lovins

The vast majority of energy loss is through the windows

Residential Examples

Envelope performance – IR Images

Envelope performance – IR Images

Envelope performance – IR Images

Envelope performance – IR Images

Envelope performance – IR Images

Superwindows’ ten hidden benefits

1. Saved heating energy (4–7x double glazing’s insulating value)—* the only benefit normally counted *

2. Save cooling energy, + fan/pump energy is proportional to flow3

3. Radiant comfort (half of comfort sensation) 4. Downsize/eliminate space-conditioning capacity5. Lower construction cost (avoids ducts, etc.)6. No perimeter zone heating7. Reduced fading from ~20less UV <380 nm8. Reduced noise9. Less/no condensation and sash rot10. Improved daylighting11. Human productivity

Benefits courtesy Amory Lovins

• High Thermal insulat ion – Advanced w indows and glazingsneed to move beyond the norm to deliver full frame thermal performance that is 2-10X better

• Dynamic glazings – These include both dynamic vision and dynamic thermal control. Viable technology w ill be in the market in 1-5 years.

• Building Integrated Photovoltaics (BIPV) – The f inal advancement for w indow technology. Viability and benefit is TBD.

Three Generations of Window s

Courtesy Amory Lovins ref. NYT 2008

Double Glaze: U = 0.5

+ Gain

- Loss

1973 1980 2010 2020

Single Glaze: U = 1

1990

Low “e” U = .35 (Energy Star)

2000

R6 Window U = 0.17(Dynamic Niche)R10 Window U = 0.10(Dynamic Wide Spread)

Three Generations of Window s

Source: Marc LeFrance, DOE

High Thermal Performance Glazing

DOUBLE GLASS PATENT, Thomas Stetson – 1865

Key elements to thermal performance

Image courtesy Serious Materials

Triple pane (SCF) thermal performance

Center of glass performance for one current IGU/w indow manufacturer

Image courtesy Serious Materials

Triple pane (SCF) thermal performance

Center of glass performance for one current IGU/w indow manufacturer

Image courtesy Serious Materials

Triple pane (SCF) thermal performance

SCF Technology

Incorporating high performance frames

Typical Aluminum, Dual Pane Low-E

FG insulated frame ,Triple pane

Note: Modeled via THERM 6.1 Simulation software, Lawrence Berkeley National Labs

Models of window cross sections – aluminum vs fiberglass

• U factor (FF) = 0.151• U-factor (COG) = 0.14• SHGC = 0.27• Tvis = 0.49

• U factor (FF) = 0.399• U-factor (COG) = 0.24• SHGC = 0.45• Tvis = 0.64

Image courtesy Serious Materials

Air infiltration as the final piece

• Air inf ilt rat ion is a topic of grow ing focus.

• Minimally tested – AAMA only requires a pass / no pass level of performance at this t ime.

• Passive House more thoroughly addresses this w ith a limits. This theme may gain tract ion in the future.

Dynamic glazing

• A dynamic glazing is one that can act ively change its physical propert ies of either:• Visual Transmission (Tvis)• Thermal/Infrared transmission (SHGC)• Or both

• A dynamic glazing is one that can act ively change its physical propert ies via:• Electrical/user control - actively• Environmental condit ions - passively• Or both

Active dynamic glazing - electrochromics

• Sage page

•Selkowitz study

Images courtesy SAGE Electrochromics

Typical embodiment with visible light transmission (Tvis) switching between 5 and 65% (LBNL)

Benefits:• Dynamic daylight control• Reduced HVAC loads

Concerns:• High cost (> $80/sf)• “ Clear” mode still somew hat

hazy w ith some electrochromic technologies

Active dynamic glazing - electrochromics

Images courtesy SAGE Electrochromics

Passive dynamic glazing

Benefits:• Dynamic daylight control• Reduced HVAC loads• Low er installed cost (~

$20/sf)• Possible as a retrofit

Concerns:• Availability• Unw anted activation • Service life

Images courtesy RavenBrick LLC

Passive dynamic glazing

Benefits:• Dynamic daylight control• Reduced HVAC loads• Low er installed cost (~ $20/sf)• Possible as a retrof it

Concerns:• Availability• Unw anted activation • Service life• Spotty visual f ield

Images courtesy RavenBrick LLC

Other dynamic glazing

• Hybrid dynamic glazing - Sw itches on per environmental condit ions, off w ith voltage:• Similar cost to tradit ional EC systems• Wiring and controls are required• Better tuned to energy savings than pure active types

• ‘ IR specif ic’ passive glazing:• Extremely low cost compared to other technologies• Pure passive, no controls • No change to Tvis• Available as a retrofit solution

Dynamic glazing - $ benefits

• A 2003 ASHRAE study found that buildings with low-E glass saved an average of 8-15% total annual energy (heating, cooling, and ventilation) costs,

• Addition of dynamic glazing (where SHGC varied from 0.26 and 0.40) saved an additional 6-19%.

• Low-E glass reduced peak cooling loads by 2-14%, and dynamic glazing an additional 5-38% reduction in peak cooling load, allowing downsizing of the building’s AC system.

• The report concluded that dynamic glazings “offer the potential for significantly greater HVAC savings than can be achieved with currently available high-performance windows”

• For large buildings across multiple climate zones, the pay-back is about 5-8 years (@ $25/sf).

Source: Energy Savings of EC Windows in the US Commercial Buildings Sector, LBNL, 2004

Source: Performance Criteria for Residential Zero Energy Windows, 2007

• A residential study w ith two teachings:

• Dynamic glazing can have a signif icant posit ive energy impact

• Effective dynamic w indows require a low u-factor to work

Dynamic glazing - research

BIPV glazing

courtesy SunTech Corp.,

Building integrated photovoltaics represent the third generat ion of high performance glazings

• Depending on the format, BIPV provides moderate power generation (avg. 45W - 100W/m² )

• May be integrated into required structures such as atria, shades, aw nings

• In some cases, can be used for view ing surfaces

• Is not f inancially viable at this t ime

BIPV glazing – light transmitting

Images courtesy SunTech Corp.,

Light transmitt ing surfaces w ith energy output of approximately 100 W / m²

Current state-of-the-art PV generates approx 1000 W / m²

•Crystal ball multiple technologies

•$/$ has to work out

10% light transmission44 W /m²

BIPV glazing – viewable

•Crystal ball multiple technologies

•$/$ has to work out

5% light transmission50 W /m²

BIPV glazing – viewable

•Crystal ball multiple technologies

•$/$ has to work out

Images courtesy SunTech Corp.,

1% light transmission55 W /m²

BIPV glazing – viewable

BIPV glazing – viewable

Image courtesy SunTech Corp.,

Advanced Glazing Case study - Retro

• SG 8 3/16_SB60• R-value: 7.7, SHGC: 0.34, VT: 0.63• Interior Glazing retrofit, $4/sqft labor• Product cost in volume, $7.21/sqft

The Situation The Solution

• Circa 1962 windows, 6 inches deep• R-value: 1.75, SHGC: 0.50, VT: 0.47• 1662 windows, 60,000 sqft total

SCF IGU Package

Image courtesy Serious Materials

Two energy model results

Base case

Modeled improvements

Advanced Glazing Case study - Retro

Advanced Glazing Case study- Retro

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

Post Energy Efficiency Retrofit with Current

Windows

Serious Windows Retrofit, R7.7

Gas Consumption / Year(BTU x000,000,000)

33% Reduction

0.00

500,000.00

1,000,000.00

1,500,000.00

2,000,000.00

2,500,000.00

Energy Savings (NPV) Investment in Serious Windows

SCF Cost-Effectiveness

SCF Retrofit R 7.7

SCF Retrofit R 7.7

Case study – New hi-rise office

• 20 story structure

• 400,000 ft2. total area

• Window-Wall-Ratio is 50%

while the

• Lighting density is 0.8 W/ft2

• Equipment power density is

0.5 W/ft2

Image source: http://www.mysketchuprenderings.com/riverpointe-office-building

Case study – New hi-rise office

Office Energy Cost Savings (compared to PPG SB60)

0%

2%

4%

6%

8%

10%

12%

14%

16%

P1-

AT

L

P3-

AT

L

P4-

AT

L

P5-

AT

L

P1-

MIN

P3-

MIN

P4-

MIN

P5-

MIN

P1-

PH

X

P3-

PH

X

P4-

PH

X

P5-

PH

X

P1-

SE

A

P3-

SE

A

P4-

SE

A

P5-

SE

A

En

erg

y C

ost

Sav

ing

s [%

]

Source: Architectural Energy Corporation, 2009.

Case study – Example hi-rise office

25-year Life Cycle Savings(over single clear glazing, 7% fuel escalation rate)

$9

$10

$11

$12

$13

$14

$15

$16

ATL

- SB6

0

ATL

-SB

70XL

ATL

- SG

-6

ATL

- SG

-8&

9

ATL

- SG

-20

MIN

- SB

60

MIN

-SB

70XL

MIN

- SG

-6

MIN

- SG

-8&

9

MIN

- SG

-20

Life

Cyc

le S

avin

gs [m

illio

ns o

f $]

Source: Architectural Energy Corporation, 2009.

25-year Rate of Return (over single clear glazing)

0%

5%

10%

15%

20%

25%

ATL - SB70XL ATL - SG-6 MIN - SB70XL MIN - SB-6

Rat

e of

Ret

urn

[%]

3% escalation

5% escalation

7% escalation

Source: Architectural Energy Corporation, 2009.

Case study – Example hi-rise office

A last glazing case study - sound the alarms

Source: McGraw-Hill, Green Building Retrofit and Renovation: SmartMarket Report, 2009.

A last glazing case study - sound the alarms

Source: McGraw-Hill, Green Building Retrofit and Renovation: SmartMarket Report, 2009.

Summary

Source: Mike Noble, BKL Consultants, Ltd.

• Glazing is a classic design problem that requires balance of– Thermal comfort, energy efficiency, light quality– View, daylight, connectivity with the outdoors

• First priority to building envelope performance, national energy efficiency

• 50% by 2030 would have– Saved 3 Q BTUs– Reduced GHG equal to 150 M metric tons of CO2 (28M cars)

• 50% by 2050 would – Saved 100 Quad BTUs– Reduced GHG equal to 6 B metric tons of CO2