© 2011 Underwriters Laboratories Inc.
Quality and Reliability ofPV Power Plants
Peeyush GuptaDirector – Sales & MarketingUL India Pvt Ltd
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SPV – heralding a new future in Sustainability• With abundant solar cover in India, the potential
of Energy Self-reliance is immense• SPV is roughly 1% of India’s Installed energy
capacity of 200GW – but the potential is much higher.
• Phase – 2 of JNNSM vital to meet RE targets• With 16-18% T&D losses, insufficient Grid
connectivity and high cost of land acquisition, Off Grid PV could be the answer to the energy deficit – but poses fresh challenges in safety and reliability.
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Trends and studies in the PV industry• Policy incentives fuelled 33GW of
capacity expansion in 2012.• Cost of power fast approaching Grid-
parity levels.• Module prices dropped by over 56%
since 2011, drop continues.• Maximizing cell efficiency and system
yield are priority areas of technology. • Safety, Quality and reliability concerns
rising: Fire and Electrical shock concerns,
particularly in Roof-Top systems Overall efficiency of PV systems. Module performance and degradation Bankability of PV systems : guaranteed
returns over the entire lifetime of the system.
• Cables, connectors, and Junction Boxes highly prone to failure.
• Urgent need to create confidence in market on long-term viability of the technology.
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Performance of PV Power Plants
Factors Contributing to Performance Site Selection Choice of Technology Plant Design Quality of Equipment Installation Practices Operation and Maintenance
CUF based on plant data from Gujarat (January to April 2012)
JNNSM – Phase1 Batch 1 – 20 X 5 MW = 100 MW
Highest CUF – 26.67%Highest Net Exported Power – 987,731 KWh
Lowest CUF – 17.88%Lowest Net Exported Power – 659,600 KWh
US study on average Module degradation per year
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PV System Value Chain
Project Proposal
Financing / Equity
Design of System
Engineering Procurement
and Construction
Final Inspection, Commissio
ning
Operation and
Maintenance• Detailed Project Report• Site assessment and
Yield
• Modules• Inverters• BoS (Cables,
structures etc..)
• Site Lease / purchase• Financial Assessment
of DPR. • Return on Capital
Investment• Lower P&M costs
• System design• Sourcing of
components• Installation and
commissioning
• Quality checks on installation.
• Grid connectivity
• Distribution, storage• Condition Monitoring• Ensuring plant
performance at optimum levels
Quality through Design
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Planning and Engineering Site Assessment Assessment of Environmental Conditions PV plant layout and calculation of shade Assessment of module technology options Review of Technology Selection Criteria Electrical cabling Civil structures Control and instrumentation Power evacuation Review of conceptual plant design(s) and
technical description / specification of components
Energy yield estimate Monitoring & Control Project financial model appraisal ‘IEC62446 : Requirements for system
documentation, Commissioning Tests and Inspections’ can be used as a guideline
Modeling techniques used to predict plant performance
Quality & Monitoring Vs. Failure Rate
Quality of System Components
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PV Module – Fire safety and performance Intended performance of cells and PV
panels, Hot spot, performance in harsh environment conditions.
Module tests as per IEC61215, IEC 61730, UL1703, IEC61646, IEC61701,
PV Inverter – Performance Issues Efficiency, Failure of Components Central Inverter Vs String Inverters Inverter tests as per IEC61683, UL1741,
IEC60068, IEC 62109 and EN 50178.
BoS – Quality and Reliability Flammability, corrosion and ingress protection, prevention of electrical shock and
protection of faults Combiner box as per UL 50, UL50E, IEC62208. Circuit Breakers type tests as per UL/IEC 60947, EN50521 Cables as per IEC60189, UL 4703. Counterfeit products – how do we safeguard ourselves?
Commissioning and Post Commissioning Checks
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Reliability of PV modules Accelerated stress tests to determine MTTF
in actual use. Performance of PV modules at High
Temperatures and low irradiance as per IEC61853-1.
Potential Induced Degradation (PID tests) Reliability vs. Durability vs. Failure
Commissioning Checks As per IEC62446 for Grid Connected systems IEC62124 for Design verification of stand-
alone PV power plants. Installation checks as per local electricity
codes; training of installers.
Post Commissioning Periodic Verification of Power Plant
Performance Ratio (PR). Condition Monitoring and System Checks. On-Site PIV measurements
Performance of PV Installations
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Major Safety Issues
• A robust mechanism of component type testing and installer training is required to ensure operator and consumer safety
• Roof top systems pose an immense challenge in terms of consumer safety – primarily fire and shock.
Ensuring Quality and Reliability of PV systemsVerification of Design, Sourcing Detailed Project Report
Bid Evaluation
Review of Vendor drawing- post E P C Award
Monitoring & Supervision of activities during Erection & Commissioning
Quality Inspections
Verification of Solar Installation and Performance Energy Yield Estimation and
comparison with that of E P C
Design Specification and documentation Vetting
Installation Process
Post Installation process
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An Independent verification by a 3rd party provides higher confidence to the project developers and financial community that the PV Power Plant is designed, built and
commissioned according to internationally accepted standards and meet the requirement of local electric codes.
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Summary and Next steps• The importance of Solar Energy to meet the
energy needs of India is unquestionable.
• The PV eco-system is a complex one with several stakeholders – its critical to involve all stakeholders to ensure Quality.
• At the policy level, standards / regulations are necessary to ensure Quality and Reliability and to bring confidence into this technology.
• Independent verification of contracts and installations can ensure quality.
• Failure Analysis including maintaining a central database.
• Adapting standards to real-time field conditions.
• Development of a ‘Reliability Scorecard’ for the PV systems installed.
High Quality, Safe and Reliable Solar Systems… Need of the Hour