Solar energy is one of the most commonly exploited renewable resource globally. Integration of power from solar to the main grid can either bring positive or negative impact which normally depends on their size and location. The size and location is very crucial if they will have to solve any problem because not all parts of the system needs more power. In this paper the most appropriate size and location of the solar photovaltaic (SPV) was obtained using Particle swarm optimization (PSO) technique. The IEEE 9 bus system was used and the main objective of this optimization problem was reducing active power losses. The algorithm was applied in a number of cases each with different number of locations of the SPVs. Two different locations proved to be a good option and bus 9 the most optimal.