In this study, a water-saturated microencapsulated phase change material (MEPCM) layer was attached to the back of a photovoltaic (PV) panel to form a MEPCM-PV module that floats on the water surface. Subsequently, numerical simulations were used to analyze the capabilities of this module for controlling the PV panel temperature and power generation efficiency during daylight according to the local summer climatic conditions (including air temperature, sky temperature, wind speed, solar irradiation, water temperature, and water flow rate). The melting point (30 and 28 degrees C) and thickness (5 and 3 cm) of the MEPCM were investigated. The power generation efficiency improved when a 5 cm water-saturated MEPCM with a melting point of 30 degrees C was attached to the back of the PV panel. (C) 2014 Elsevier Ltd. All rights reserved.