Electricity generated using photovoltaic system can only be commercial if the photovoltaic modules operate reliably for 20-25 years under field conditions. Understanding the performance degradation of photovoltaic modules is critical for optimizing its financial viability. Performance degradation of photovoltaic modules is due to multiple factors such as installation site and module technologies. In order to gain insight on performance degradation of crystalline silicon PV technology in harsh environment, a degradation effects study of c-Si photovoltaic modules in desert environment was carried. The main contribution of this paper is focused on the evaluation of c-Si PV modules performance that operated in extreme environmental conditions. This evaluation usually consists of I-V curve field measurements and visual inspections. (C) 2017 Elsevier Ltd. All rights reserved.