Reliability analysis of temperature step-stress tests on III–V high concentrator solar cells

III–V high concentrator solar cells are promising candidates for reducing the cost of photovoltaic electricity in terrestrial applications. However, the knowledge on the reliability of these devices is still scarce. Solar panels based on III–V high concentrator solar cells are about to be commercially available, and must compete with conventional systems based on silicon which have guarantees of approximately 25 years. This paper presents results of step-stress accelerated ageing tests carried out on these solar cells. Data have been analyzed according to Weibull reliability function. This analysis yields a lower value of the MTTF of 2.02 × 105 h (i.e. about 69.2 years assuming 8 h of average operation per day in a year) for a confidence interval of 90%.