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The consequences of failure for balance-of-systems components (such as photovoltaic (PV) cable connectors) include offline module string(s); low system voltage; arc, ground, insulation, and overtemperature faults; triggered fuse(s); system shutdown; and fire. The degradation modes for connectors are studied here through an industry survey and its subsequent examination, which are compared with field-degraded specimens. A total of 117 specimens were obtained from a variety of locations and climates or accelerated tests. A failure analysis for connectors from PV installations was developed (and applied to 54 specimens), including nondestructive examinations (photography, a custom resistance–current scan, and X-ray computed tomography) and destructive examinations (featuring milling of the external plastic, extraction of the internal convolute spring, and potting and polishing in cross section). Surface and through-thickness composition of the metal pins and springs was quantified using scanning electron microscopy with energy-dispersive X-ray spectroscopy. Fourier transform infrared spectroscopy was used to verify the base polymer materials and compare the chemical structure of the connector body, bushing, end nut, and o-ring. Thermogravimetric analysis and differential scanning calorimetry were used to further verify the degradation of the same polymeric components.

A forward-looking research opportunity number (RON) is defined for photovoltaic reliability researchers. The RON enables researchers to prioritize their efforts toward the highest impact. For a given degradation mode, the RON is based on three factors: the effect on levelized cost of electricity, the susceptibility of future module products, and the maturity of accelerated tests that can detect and quantify the mode. Reporting bias is avoided because the RON does not rely on polls. The RON is derived for three example cases: light and elevated temperature degradation, backsheet cracking, and antireflective coating abrasion. These examples demonstrate that targeted research has reduced the risk for these modes over the last several years.

The current study explores the experiences of nonresidential fathers and the potential barriers to engagement with their children. Using a phenomenological approach, we explored issues of perceived parenting supports, co-parenting, and self-efficacy, and how these might impact fathering behaviors and attitudes. We conducted semi-structured interviews and focus groups with 12 self-identified Black fathers in Fulton County Georgia. The results indicate that co-parenting issues and lack of community support were viewed as barriers. Despite the challenges they faced as fathers, men often demonstrated resilience and persistence in being a positive presence to their children. This study highlights the need for social service organizations to increase services they offer to fathers paying close attention to nonresidential fathers.