Photovoltaic system reliability and durability

Having evolved from a niche source to a leading source of electricity, solar power has seen a significant and steady decline in production costs over the past two decades, making it one of the cheapest power generation solutions in the world. Many countries are seeing their share of electricity generated by photovoltaics increase, with it now accounting for a few percent—or even more—of their electricity mix. Its success is partly due to its simplicity and robustness: optically and electrically optimized semiconductors are exposed to sunlight and produce electricity that is virtually proportional to the amount of light received. This apparent simplicity and existing feedback show that the lifespan can exceed 25–30 years in most cases; this figure is also included by photovoltaic module manufacturers in their production warranties, making them everyday items with one of the longest warranties available.

By 2026, solar power is therefore seen as a low-carbon, inexpensive, variable yet reliable source of electricity, with a limited risk of failure. These factors explain the rapid spread of this energy source around the world, with annual growth rates often exceeding 20% since the 2000s. However, this growth rate also means that this energy source is still in its infancy, with half of the world’s installed capacity being less than three years old. Feedback on systems from the last century is generally positive, but the technical and economic context is putting pressure on the industry, which regularly faces overcapacity and is forced to lower manufacturing costs to survive while continuing to improve performance (i.e., increasing conversion efficiency). These constraints allow the photovoltaic industry to achieve extraordinarily low costs, but also increase the risk of reliability failures due to certain manufacturing shortcuts, poor mastery of new technologies, or the choice of materials that are certainly low-cost but unable to withstand environmental stresses over several decades.

While such "accidents" remain rare, the diversification of processes and materials used to continuously improve conversion efficiency at ever-lower costs remains a pressing issue. To minimize these accidents, we cannot wait decades to confirm that everything will be fine! Several steps can be taken to ensure the safety of the best components. First, one must have a clear understanding of the composition of a solar power plant, particularly the photovoltaic modules, and then fully grasp the potential sources of degradation that could affect the components of a solar power plant. Finally, once these concepts are understood, it becomes possible to consider several solutions to limit future risks of failure: on-site quality controls at the time of installation, as well as inspections directly...