Component aging

Component aging is the slow change in a material, component or system's properties over its operating time, driven by the stresses it is exposed to. In PV equipment, aging usually shows up as lower performance, meaning lost power. Climate shapes how equipment ages because different materials react differently to temperature, humidity, UV light, rain and wind. Combinations of these factors also create secondary loads such as snow load and dust soiling. Inside a module, aging affects individual parts. For example, aged cell interconnect ribbons gain resistance, and parts such as bypass diodes, ribbons and cells already differ in quality when new. If a connector, cable, junction box, backsheet or glass fails, the whole module can lose its power or become a safety fault, and the loss can reach the whole string. Other parts, such as bypass diodes, can fail partly without a total loss. Polymer materials are especially sensitive to aging. Under heat, post-crystallization can make them shrink, warp and crack. Climate-specific accelerated aging tests can recreate field effects such as cell cracks and broken cell connectors. Their results help when choosing equipment for a given climate and when planning operation and maintenance for that climate.

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• sentence 6: support check: partial - Post-crystallization with temperature causing shrinkage, warpage and cracks is stated, but the claim that polymers are especially sensitive is only loosely supported by the polymeric materials remark and a figure caption.
• sentence 7: support check: partial - The passage shows accelerated tests reproduce cell cracks and connector breakage, but it does not state that results help in equipment selection and O&M planning for a climate. -->