The presentation provides an overview of PVQAT: International PV Quality Assurance Task Force - historical perspective, projects, climate - specific (use - environment -specific) durability testing, consistency of manufacturing, system verification, IECRE vs PVQAT, how to become involved, current status and multiyear targets, goals for today.

The performance of photovoltaic (PV) modules and their component materials under the stresses in the outdoor environment is the most important indicator of reliability, durability, and safety of PV modules throughout their service life. Tedlar polyvinyl fluoride films have been a key component in backsheet component structures and used in PV modules that have been in the service environment for over 25 years. The performance of fielded modules and components can be compared with the performance in durability tests using other backsheet materials including polyethylene terephthalate. Accelerated testing protocols are described including UV exposure based on solar irradiance in different climates and relevant albedo levels for exposure of the back of PV modules. The change in critical performance properties in durability tests including damp heat and UV is compared with backsheets that are extracted from fielded modules. Analysis of mechanical and chemical properties of the inner and outer layers of backsheets that are removed from fielded modules is examined. Area-specific coring techniques that are followed by layer composition analysis were also used to understand fielded module failure mechanisms/defects. The impact of extended damp heat and UV on backsheet properties and module performance that is observed in the field is further quantified through measurement of mechanical, optical, electrical, and permeability properties of the backsheet and power, electrical insulation, and physical properties of the modules. Correlations between field performance and accelerated testing are demonstrated. The first results for sequential and combined stress testing are described and compared with the field performance. A comparison of two large and diverse sets of modules from two different locations (EU and Japan) is discussed, and the power loss with field exposure period and the impact of backsheet is described.

This presentation gives the historical background of the creation of the International PV QA Task Force as an introduction to the PV Module Reliability Workshop.

Photovoltaic (PV) customers need to have confidence in the PV modules they purchase. Currently, no test can quantify a module's lifetime with confidence, but stress tests are routinely used to differentiate PV product designs. We suggest that the industry would be strengthened by using the wisdom of the community to develop a single set of tests that will help customers quantify confidence in PV products. This paper evaluates the need for quality assurance (QA) standards and suggests a path for creating these. Two types of standards are needed: 1) QA of the module design and 2) QA of the manufacturing process.

This presentation outlines review requirements for quality assurance (QA) rating systems, logical design of QA systems, and specific tasks for break-out session 1 of the 2011 International PV Module Quality Assurance Forum.

This paper presents statistical analysis of the behaviour of the electrical performance of commercial crystalline silicon photovoltaic (PV) modules tested in the Solar Test Installation of the European Commission's Joint Research Centre from 1990 up to 2006 to the IEC Standard 61215 and its direct predecessor CEC Specification 503. A strong correlation between different test results was not observed, indicating that the standard is a set of different, generally independent stress factors. The results confirm the appropriateness of the testing scheme to reveal different module design problems related rather to the production quality control than material weakness in commercial PV modules.

Qualification tests of terrestrial photovoltaic (PV) modules have been carried out at the European solar test installation of the European Commission's Joint research centre, Ispra from 1981. Since 1990, all tests have been based on the IEC 61215 Standard, or its direct predecessor, Specification 503 [1] The performance measurements on all of these modules now form an extensive database of results for electric performance degradation, after applied qualification tests. Many of the stress tests results obtained by the ESTI Laboratory have already been published and presented [2] [3].This paper presents statistical analysis of selected results of the behavior of crystalline silicon modules from the data base of modules tested from 1990 up to 2006

Since 1981 the European Solar Test Installation of the European Commission's Joint Research Centre id performing qualification tests on terrestrial photovoltaic (PV) modules. Since 1990, the test standard applied is IEC 61215, or it's direct predecessor, Specification 503. The paper describes the results of more than 125 module types tested, focusing on the reliability and lifetime.

This paper discusses the characterisation of different CdTe modules and the main issues raised by such technology compared to conventional Si devices, from indoor STC (1000 W/m2, AM1.5G spectrum, 25°C) performance to the actual outdoor field data. The choice of the reference detector, indoor to outdoor calibration, hysteresis, transient effects and stability are variables that make the intercomparison of data difficult, and this work aimed to contribute to their classification and systematisation. Indoor calibration values reasonably agree with outdoor performance when a spectral mismatch factor correction is applied to short circuit current. However, the fill factor is underestimated. Temperature coefficients show different trends and classic approaches to translation equation for temperature and irradiance fail. Finally, the importance of STC performance with respect to actual field performance was analysed over a period covering 3 months of outdoor testing.

This paper describes the results of in-situ hydrogen permeation measurements of aluminised martensitic steels (F82H-mod. and MANET) under gaseous hydrogen and liquid Pb–17Li/hydrogen while being subjected to a cyclic tensile load. The results are presented in terms of the permeation reduction factor (PRF) of the coating. The vacuum plasma sprayed (VPS) coated specimens exhibited only a moderate PRF when tested under gaseous hydrogen (in comparison to previously reported data) but an even lower PRF when tested under liquid Pb–17Li/hydrogen. In particular, the coated MANET tube exhibited an increasing permeation rate with time for sequential measurements carried out at 830 K, which was attributed to the effect of wetting of the surface by the Pb–17Li. Although thermodynamic calculations have indicated that the aluminide coating should form alumina down to very low aluminium contents (xAl=0.0133 in oxygen-saturated Pb–17Li at 773 K), they also show that the thermodynamically favoured product is LiAlO2.

This paper describes the results of uniaxial tensile tests on two low activation steels F82H-mod. and OPTIFER IVb. The tests were performed under vacuum and in liquid Pb–17Li at temperatures of 250°C and 400°C at a constant displacement rate of 0.1 mm min−1, which corresponded to an initial strain rate of 1.1×10−4 s−1. Neither F82H-mod. nor OPTIFER IVb exhibited a liquid metal embrittlement (LME) susceptibility in the tempered fully martensitic state. However, tests of the heat affected zone (HAZ) specimens indicated an LME susceptibility for both steels tested at 250°C in Pb–17Li, while increasing the test temperature to 400°C led to the recovery in ductility. The effect of post-weld heat-treatment (PWHT) of the HAZ specimens of 750°C/1 h for F82H-mod. and 730°C/3 h for OPTIFER IVb was sufficient to regain the majority of their original mechanical properties.

EXECUTIVE SUMMARY TABLE OF CONTENTS 1 OBJECTIVES OF THE PROJECT 2 PROJECT OVERVIEW 3 IMMUNITY TESTS OF AC-MODULE INVERTERS 3.

The thermodynamic stabilities (ΔriG) of various ceramics towards PbLi alloys have been evaluated as a function of temperature, lithium composition and, for lithium, non-metal solute concentration. For non-metal saturated alloys, both increasing temperature and decreasing lithium composition (from lithium to Pb-17Li) lead to increased stability (more positive ΔrG values). Reducing non-metal solute concentration in lithium by cold trapping leads to decreased stability. Of the ceramics presently being assessed as coating materials, AlN, TiN, TiC, Y2O3 and CaO are stable in reactor grade Pb17Li and reactor grade lithium, β-SiC, Al2O3, SiO2 and MgO are stable in Pb17Li but not lithium and Cr2O3 is unstable in both breeders.

In a previous work, it has been shown that lower aluminium content aluminide, having the same permeation rate reduction as the higher aluminium content, exhibited a lower hardness and greater ductility and therefore greater crack resistance than the higher aluminium content. In this work we combine this characteristic with a post-oxidation to obtain a further deuterium permeation reduction. The post-oxidation was performed in air at 1023 K for 15 h and at 1223 K for 10 h and 1 h. The maximum deuterium permeation rate reduction obtained is very moderate (maximum of a factor 500 for 1 h at 1223 K) as compared to that of the non-oxidised aluminide specimen (two orders of magnitude) and is constant in the temperature range studied (573–800 K). This method has the technological appeal of using air rather than the controlled environment used by other authors.

TIG welding of 12 mm thick plates of MANET II steel was accomplished using filler material of the same composition. Tensile tests, at a constant displacement rate of 0.1 mm min−1 (corresponding to an initial strain rate of 1.1 × 10−4 s−1), were carried out on specimens consisting solely of the weld, HAZ and bulk material under vacuum and liquid Pb17Li at 250 and 400°C. The post-weld heat treatment (750°C/4 h air cooled) which was given to the welded plates was sufficient to prevent any liquid metal embrittlement. The presence of oxide inclusions and pores in the weld reduced the extent of plastic strain at rupture exhibited by some of the welds.

This paper describes the production and permeation measurements of three different aluminide coatings on the surface of MANET II stainless steel. The coatings were produced by vacuum plasma spraying pure aluminium (approximate to 100 mu m) on to the steel, which was subsequently heat treated to produce an aluminide layer on the MANET. The relationship between the aluminum content of the coatings and their effectiveness as permeation barriers, due to the greater or lower resistance to crack formation was manifest. The coatings with a lower aluminum content presented the largest permeation reduction (2 orders of magnitude).

The thermodynamic stabilities of various barrier materials and the self-healing of aluminide coatings in oxygen saturated Pb-17Li have been evaluated.Binary nitrides and carbides are stable, but binary oxides display diverse behaviour; Al2O3 and MgO are stable, Cr2O3 is unstable to reduction to chromium metal and SiO2 exhibits intermediate properties. Ternary oxides behave similarly, but are intrinsically more stable, their stabilities increasing with Li2O content.Self-healing of aluminide barriers should occur to form either Al2O3 or LiAlO2. the latter being favoured. For Fe-rich Fe-Al solid solutions, self-healing is dependent on their aluminium content; at 723 K, Al2O3 or LiAlO2 formation only occurs for x(Al)greater than or equal to 1.69 mol% Al or x(Al)greater than or equal to 0.20 mol% Al, respectively.