This paper proposes a renewable energy resource (photovoltaic) to generate green and halal energy for household and feeding the excess energy into the Nigeria National Grid Network. The energy demand in third world nation like Nigeria will increase in nearest future. The renewable energy is one of the alternative energy sources that could satisfy the increasing energy demands. Nigerians depends heavily on fossil fuel to generate its electricity needs. Fossil fuels are depleted and the main source of pollution. Photovoltaic (PV) systems generate electricity directly from the sunlight without any emission of global warming gases, and the fuel is free. In order to optimize the performance of PV systems their operation should be well understood. In this paper, we present the modelling of a real 1.2 MWp photovoltaic system. The PV power plant is tied to the grid. The PV array, the DC/DC converter and the DC/AC inverter are modelled and implemented in Matlab/Simulink. The controller of the grid-connected inverter is modelled to achieve constant voltage, constant frequency and to be synchronized with the grid. The system is simulated under Nigeria weather conditions and the results are acceptable.