Proven Power and Lasting Value DuPont Photovoltaic Solutions Materials Matter™ for PV Module Quality and Effective Risk Management 5th EQ Solar & Wind Power Investment and Tech Summit 22 February 2017, Mumbai Rahul Khatri Technical Manager, India DuPont Photovoltaic Solutions Photovoltaic Solutions

Current Risk Mitigation Methods Are Not Effective Will Your Modules Perform for 25 Years in the Field? Assumptions Annual Power Degradation: 0.7% / year Risk Mitigation Methods Warranties IEC Certification Tier 1 Module manufacturer insolvency Claim settlement can take 4 – 6 months Not a lifetime test Many instances of failures of IEC tested modules Ranking is not based on module quality Current Risk Mitigation Methods Are Not Effective 2

Materials Impact Module Performance in the Field 3rd Party Studies: An Increasing Trend in Module Defects PV module defects increased from 19% in 2013 to 48% in 2015, according to research conducted by TUV1 In addition to potential induced degradation (PID) and glass breakage, defective backsheets are contributing to serious defects of solar modules Materials Impact Module Performance in the Field . 1 TUV Rheinland Intersolar 2015, Roundtable Solarpraxis 3

Consequences of Compromising on Module Quality… Early Signs of Backsheet Failure Backsheet Type: PET Based 4 years old plant in North China Significant yellowing of backsheet (b* = 8-10) Bubbling and Delamination Yellowing is a Visible Sign of Material Degradation (Brittleness) and Can Lead to Cracking

Backsheet Degradation Can Lead to Catastrophic Failures Backsheet Type: PET 5 years old installation in Spain Yellowing and Cracking 32% power loss over 5 years (6.4%/year) Some modules failed wet leakage test – Safety Risks Backsheet Type: PVDF 4 years old installation in North America Severe cracking and delamination of PVDF film 57% of the installed modules impacted Backsheet Type: PET 9 years old installation in West China Severe cracking, peeling and yellowing Backsheet Type: Polyamide (PA) 5 years old installation in Italy Severe cracking and delamination of PA film Inverter tripped due to current leakage

Unproven Materials Increases Risk of Module Failure Case Study: Polyamide Based Back-sheets History Introduced about 6 years ago as a low cost alternative Passed all IEC and internal tests Many manufacturers started using it due to lower cost Current Scenario Multiple cases of backsheet cracking after 3-4 years in the field Generation losses due to inverter tripping in some cases 5-7 GW of currently installed systems with Polyamide based backsheets are at significant risk Spain - 4 years old, 2.3 MW field, based on 2 module types China - 4 years old, large cracks Italy – large crack tripped inverter Root Cause Unproven materials increases risk of module failure Existing tests standards are ineffective to predict field performance Unproven Materials Increases Risk of Module Failure 6

Alleviating Module Risks Requires Focus on: Use Proven Bill of Material Adopt Test Methods That Better Simulates Field Ageing Mechanisms Crystalline Silicone PV Module Structure Damp Heat UV Thermal Cycling 7

Specify Use of Proven BoM for PV Modules Proven Bill of Materials 11 – 27 years old installation in China <0.8% power annual power loss All modules have Tedlar® PVF film-based backsheets Specify Use of Proven BoM for PV Modules 8

Key Learning Focus on quality for healthy financial returns Module Bill of Materials (BoM) is extremely critical for module reliability and durability Focus on using proven BoM to mitigate failure risks Share to help industry learn & grow

When Materials Matter™, go with the proven leader When Materials Matter™, go with the proven leader. What you’ll get is proven power and lasting value you can count on for the long term, for greater peace of mind. DuPont Photovoltaic Solutions Day After Day Since presenting our first technical paper on the use of Tedlar® PVF film in PV applications nearly 50 years ago, we have become the leading PV material expert. Today, our capabilities extend from materials to modules, including fundamental PV materials science and cell and module processing, architecture and testing. We are also a PV system owner and PV electricity user, with PV systems at DuPont sites around the world. As we look to the future, our commitment only grows.   You can count on our materials to deliver proven power and lasting value because of our deep commitment to four areas:  LIFETIME PERFORMANCE DuPontTM Tedlar® is the long-standing benchmark for the industry. Newer materials have since emerged, but none demonstrate the durability and longevity Tedlar® has over its more-than-30-year history in the field. As the industry seeks to maximize returns by extending system lifetimes, Tedlar® continues to be the clear choice for backsheets. LIFETIME EFFICIENCY DuPontTM Solamet® continues to set new standards for efficiency. Solamet® is the first choice for customers who seek to continually improve solar cell and panel efficiencies, to ultimately reduce LCOE. FINANCIAL RETURNS We focus on not only delivering higher power output over the course of a lifetime, but also greater safety, peace-of-mind and lower risk, which add up to lifetime returns that are both higher and more predictable. FIELD-TESTING Recent history has shown there is no substitute for field-testing, and no one else even comes close to us in this area. We have vigorously evaluated our field-proven materials in extreme environments for over 30 years, and we continue to do so today. photovoltaics.dupont.com Copyright © 2016 DuPont. All rights reserved. The DuPont Oval Logo, DuPont™, and all products denoted with a ™ or ® are trademarks or registered trademarks of E. I. du Pont de Nemours and Company or its affiliates.

+ + Financial Returns Depend on Multiple Factors Financial Performance [Return on Investment] Energy Produced Output & Safety Performance (kWh) Cost of Capital External Factors + + Reliable PPA Module Reliability Module System Uptime Inverters & BoS Risks Operation & Maintenance Finance Insurance A mature market would improve financial performance by optimizing energy generation and reducing risks (cost of finance and insurance) through use of high quality modules and incorporating robust installation and maintenance practices. In India, the focus is more on reducing the cost of capital primarily by using cheap modules which increases risks on module performance and thus attracts higher finance and insurance cost. Moreover, this puts India’s solar mission in danger as a few large scale failures would be sufficient to dampen the interests of financers without whom the industry cannot progress Weather Focus on Optimizing Energy Generation for Better Returns