Owens Corning has developed new fiberglass products called WindStrand for use in wind turbine blades to meet increasing demands of the wind energy market. WindStrand fibers have higher modulus than traditional E-glass, allowing for designs with increased blade length and strength. Test results show WindStrand composites have improved mechanical properties including higher tensile strength and longer fatigue life compared to E-glass. Case studies demonstrate how WindStrand fabrics can enable larger blade designs with benefits like reduced structural loads and costs. Owens Corning will continue innovating fiberglass to provide a competitive solution as blade designs pursue greater efficiency.

1. Advances in Fiberglass Properties for Wind Turbine Blades
Tom DeMint
Marcus Liu
Dave Hartman
Georg Adolphs
Richard Veit
Technical Marketing
Composite Solutions Business
Owens Corning
Engineered Solutions
Copyright ® 2014 Owens Corning All Rights Reserved

2. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSOwens Corning is the leading producer of fiberglass
1938 1952 1970s 1980 1987 1996 2007
• Sales of $5.2 billion in 2013.
• 15,000 employees in 28 countries.
• FORTUNE 500 company for 59 consecutive years.
Owens Corning
listed on NYSE
Owens Corning
Fiberglas launched.
$2.5M sales
600 people
$2 Bn sales $3Bn sales
18,000 people
globally
Owens Corning purchases
Saint Gobain becomes
largest glass fiber producer

3. 37 plants in 15 countries
Inventor of all major glass types (E,ECR,S,R,H)
OC Reinforcements
OC Engineered Solutions
Composite Solutions Business ($2.5Bn)

4. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSLeading Innovation
Large capacity
furnaces provide
industrial supply
of high
performance
glass fibers
Evolution of glass fiber innovation…
• 1939: E-glass
– Boron added to glass for electrical properties
• 1965: R-glass (Higher performance)
• 1968: S and S-2 Glass®
– High strength and modulus (high melting power needed)
• 1974: AR-glass Alkali resistant
• 1978: E-CR Glass Corrosion resistant
• 1996: Advantex® ECR Glass and melting technology
– Boron free E-glass, ECR-glass (superior corrosion resistance to traditional E-glass)
– Breakthrough in melting technology for large capacity furnaces
• 2006: R and H-glass melting technology
– Combines High modulus glass and Advantex®-scale melting technology
• 2009: S-glass direct melt large capacity technology
– Production in large capacity furnaces with higher fiber homogeneity
• 2014: Windstrand® product line Superior sizing chemistry

5. How OC Helps the Wind Energy Market
Working side-by-side with customers
to develop new solutions
Leveraging our expertise for future growth
Fundamental product and process innovation
to engineer advanced composites

6. 6
Turbine Performance Trends in the Wind Energy Market

7. Market Evolution
Better reliability
• 25 year blade life
• 107 fatigue load cycles
ON-SHORE (LOW WIND)
Longer blades to harvest energy in low wind speed regions
and cold climates
ON-SHORE (HIGH WIND)
Continued pressure to reduce capital/operating costs
Requires cost effective solutions
Reduce manufacturing and operating costs
OFF-SHORE
Large turbines (8MW)
larger blades (75m - 80m, glass, carbon)
extreme environments

8. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSThe Scaling Problem
• Aerodynamic loads scale up linearly with blade length, which
of itself might not require an increase in material properties.
• However blade mass, gravitational loads, and fatigue loads
scale up exponentially with blade length.
Blade length
Weight
Material requirements are increasing with increasing blade length and mass.
Market needs higher Modulus/$, Strength/$

9. Material Data and Advances in Properties
New Products for Wind Turbine Blades:
WS2000: Advantex® E/ECR-glass with advanced sizing for epoxy
WS3000: High Modulus H-glass with advanced sizing for epoxy
Ultrablade G3: WS3000 UD fabric (epoxy)

10. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Unidirectional Fiberglass Fabric/Epoxy Laminate Modulus Trend
Source: External test lab results 2009-2014 (IMA Dresden, WMC, TPI Composites); Momentive
Epoxy resin L135/H137
Linear trend of increasing UD glass fabric modulus with
increasing FVF approaching 50 Gpa using high modulus glass
Tweek 0.600.580.560.540.520.50
50
48
46
44
42
40
Fiber Volume Fraction
UDLaminateEx,GPa,Tensile
Advantex™ E
Windstrand™ H
Fiberglass type
UD/Epoxy Laminate Ex, GPa, Tensile vs Fiber Volume Fraction
800750700650600
1200
1100
1000
900
800
700
Compression Strength, MPa, 95/5% CI
TensileStrength,MPa,95/5%CI
Advantex® E
Windstrand® H
Fiberglass type

11. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Longitudinal Modulus Ex, Measured vs. Theoretical
43210-1-2-3-4
99
95
90
80
70
60
50
40
30
20
10
5
1
Difference Measured-Theoretical Modulus E1 [GPa]
Percent
-0.2642 0.8623 9 0.427 0,241
0.04723 1.016 9 0.347 0,393
Mean StDev N AD P
ADV 78GPa
H 85GPa
Fiber
Normal - 95% CI
Source: IMA Dresden test results 2009-2014 on UD Fabrics, Momentive Epoxy resin L135/H137
210-1-2
5
4
3
2
1
0
Difference measured-theoretical
Frequency
Mean -0.08867
StDev 1.004
N 22
Ex Measured- Ex Theoretical
Glass Bulk Modulus used for theoretical calculations
 Ebulk Advantex : 78 GPa
 Ebulk H-glass: 85 GPa
We observe good agreement between measured and theoretical longitudinal laminate modulus Ex

12. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
UD/Epoxy Static Strength Properties, Characteristic Values (95%/5% Confidence Interval)
Source: IMA Dresden test results 2009-2014 on UD Fabrics, Momentive Epoxy resin L135/H137
We see a correlation between UD/epoxy tensile and compressive strength
800750700650600
1200
1100
1000
900
800
700
Compression Strength, MPa, 95/5% CI
TensileStrength,MPa,95/5%CI
Advantex™ E
Windstrand™ H
Fiberglass type
800750700650600
1200
1100
1000
900
800
700
Compression Strength, MPa, 95/5% CI
TensileStrength,MPa,95/5%CI
Advantex® E
Windstrand® H
Fiberglass type

13. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Laminate Behavior Transverse to the Longitudinal Fibers under Tension
Natural transverse contraction can be
constrained by adjacent plies (often 90o plies)
compared to a pure UD lamina.
This constraint may lead to limited
transverse cracking, which may be
acceptable in some rotor blades.
However the average Inter Fiber
Fracture strength (IFF) is measured
and used for blade designs.
IFF cracks

14. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSTensile Load Bearing Capability
Source: IMA Dresden test results 2009-2014 on UD Fabrics, Momentive Epoxy resin L135/H137
WS3000 “IFF Safety Factor” = 1.5
E-glass UD H-glass EPW17 WS3000
Lowerisbetter

15. 15
Acoustical and Fracture Surface Analysis of Transverse 45deg Tension in
Advantex/epoxy lamina panels
Source: OC WindStrand® fibers and data. Panels dry-wound roving and infused using Momentive epoxy L135/H137
E-glass UD/epoxy WindStrand UD/epoxy
Better fiber matrix adhesion leads to higher transverse strength

16. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Static Longitudinal Tensile Failure Modes, UD1800 SE1500 vs WS2000/epoxy
Source: OC test data UD1800 Fabrics, Momentive epoxy resin L035/038
UD WS2000/epoxy
UD E-glass/epoxy

17. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSUltrablade® G3 vs G2 Fatigue Performance (Stress Amplitude)
Higher Initial Static Tensile Strength Leads to Longer Life

18. 0
500
1000
1500
2000
2500
3000
3500
4000
4500
0 1 2 3 4 5 6
TensileStrength(MPa)
TensileStrain(%)
VintageE-Glass
State-of-ArtE-Glass
S-Glass
WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Strength Knockdown from Fiber to Laminate Damage Accumulation
Source: OC data on WS2000 UD Fabrics, Momentive epoxy R135/H137
0
200
400
600
800
1000
1200
1400
WS2000
Coupon
Mean
UD1200
Coupon
Mean
UD1200
Coupon
R(95%)
UD1200
Spar Cap
Mean
Fatigue
R=0.1
10^6 cycles
00 Tensile Strength 55%Vf (MPa) Knockdown
Better fatigue performance leads to longer life and lower design knockdowns
from damage accumulation
Vintage E-glass
Advantex®
S-glass
Advantex®

19. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDS
Fatigue Performance, Advantex® vs Ultrablade® UD Fabric/epoxy
6,05,55,04,54,0
700
650
600
550
500
450
400
350
LOG (N)
PeakStress[MPa]
ADV
H
Fiber
Source: Risoe / DTU tests 2013 on UD laminates, Momentive Epoxy resin L135/H137
Higher Initial Static Strength Leads to Longer Life
800750700650600
1200
1100
1000
900
800
700
Advantex™ E
Windstrand™ H
Fiberglass type
Advantex® E
Windstrand® H
Fiberglass type

20. Fabric
Handling
Molding
Performance
Mechanical
Performance
Blade Designer and Manufacturer Fitness-for-Use
• Increased longitudinal content
• “Steerable” UD fabric
• Unrolling characteristic SPC
• Short layup cycle time
• Smooth and aligned layup
• Suitable ply termination
• Efficient Infusion process
• Process Consistency
• Part Quality Consistency
Fitness-for-Use Characteristics Product Development Trend
• Reliable cycle time
• Reliable glass content
• Reliable part thickness
• 0o Tensile Modulus & Strength
• 90o Tensile IFF (Inter-fiber Fracture)
• Reliable Fatigue performance
• Polyester blades
• 50 GPa Longitudinal Modulus
•1200 MPa 0o static tensile strength
• Target IFF >90% matrix strength
• Fatigue target > 50% static @106 cycles
Many elements to the blade fabric FFU

21. 21
Case Study of High Modulus Glass Fabric

22. Case Study: Application of Ultrablade® TRIAX G3 to Root Section
 Ultrablade® TRIAX G3 fabric construction and modulus
 Effect of fabric modulus on the blade root design
 Infusion behavior

23. Wind Turbine Blade Root Connection Model (Samtech)
Single bolt and root laminate and bearing load modeled.

24. Root Connection Simulation Results
High Modulus Ultrablade® TRIAX reduces axial bold load by 17%
which can increase bold fatigue life
E-glass fabric A E-glass Fabric B Ultrablade® TRIAX A Ultrablade® TRIAX B
Ex = 28 GPa Ex = 30 Gpa Ex = 38GPa Ex = 42 GPa

25. Epoxy Resin Infusion Behavior
Area 9layers 19layers 29layers 39layers 49layers 59layers
Sample1-FWF 72.30% 72.20% 72.70% 72.80% 73.15% 73.38%
Sample2-FWF 72.35% 72.48% 72.52% 72.84% 72.98% 73.46%
Average FWF 0.72325 0.7234 0.7261 0.7282 0.73065 0.7342
Thickness 1.0998 1.0893 1.088 1.0882 1.0717 1.0716mm
mm

26. Ultrablade® TRIAX Commercialization
• Received first commercial order. 350 root sections.
• Published GL-certified independent testing reports

27. WINDSTRAND®
REDEFINING OUR PLATFORM TO MEET EMERGING INDUSTRY NEEDSSummary
• External laboratories confirm consistent and reliable results for main
design parameter (E, S, fatigue life) of current glass reinforcements and
new products like WS3000 and Ultrablade® G3 fabrics.
– Similar linear best-fit slopes at higher initial static strength lead to longer life
• Glass reinforcements continue to offer a cost effective design solutions
enabling longer and more efficient blades.
– We are pushing the UD glass/epoxy envelope, but we have not hit the upper
limit of glass blade length.
– Ultrablade™ G3 fabrics offer a cost-effective alternative to carbon
• Since 2004, over 60 epoxy and polyester blades designs have been
commercialized around the world using H-glass and Ultrablade®.
• We expect design values of 50+GPa for High Modulus UD glass/epoxy

28. Thank You
Innovation
Quality
Global Supply