Reliability measures assessment of solar water heating system under copula and general repair facilities

As a result of the increased danger involved with other energy sources like fossil fuels, thermoelectric, nuclear, hydropower, gas thermal, etc., there is a strong increase in the demand for renewable energy on a global scale. Consequently, this paper considers a solar water heating system that consists of four subsystems: j panels that work under the b-out-of-j scheme, a controller, a tank, and a heat exchanger that all combine together in a series-parallel configuration. Unit/subsystem failure is constant and tally with exponential distribution, two repairs are involved: the general repair to resolve the partially failed state and the copula repair to fix the system failure. The intent of this study is to examine the system for various reliability measures, including availability, reliability, mean time to failure (MTTF), sensitivity, and cost, as well as to determine how the results of the study will be impacted by repairs. The model's transition diagram was used to generate the partial differential equations of order one, which are solved using supplementary variables and Laplace transformation techniques. Particular examples are given to justify the obtained results, and a conclusion was drawn from the findings that copula repairs produce higher outcomes than general repairs, therefore declaring repair for optimal performance of the system.