This study examines the operational dynamics of a Photovoltaic/Thermal (PV/T) system, focused on simultaneous thermal and electrical energy generation under various conditions. The study covers PV/T system details, numerical modelling analysis and evaluates thermal and electrical output using Cellulose Nanocrystal (CNC) Nano-fluid. The main goal is to enhance PV system performance and reduce electricity generation costs. As the electrical output of the system is profoundly influenced by the operating temperature of PV cells, the integration CNC Nano-fluid is tested as a coolant to enhance PV cells’ temperature control and system efficiency. The distinctive feature of this system lies in its capacity to augment electrical energy production while ameliorating solar radiation exposure, effecting PV module cooling, and engendering recoverable thermal energy for residential applications. Through the examination of the proposed system, it is ascertained that the zenith of energy output, encompassing both electrical and thermal facets, is achieved at a solar radiation intensity of 1000 W/m2 and a cooling fluid flow rate of 1.3 kg/min, yielding 155 W and 448 W, respectively, with an attendant electrical efficiency of 17.1%. In contrast, an uncooled PV module registers an electrical power generation of 142 W, accompanied by an efficiency of 15.75%.