This article presents a genetic algorithm-based method to determine optimal location and size of the distributed generations to be placed in radial, as well as networked, systems with an objective to minimize the power loss. Several simulation studies have been conducted on radial feeders, as well as networked systems, considering single-distributed generation and multiple-distributed generations separately to minimize the power loss of the system subjected to no voltage violation at any of the buses. Simulation results are given, and the results are compared with the results of Wang and Hashem Nehrir [Analytical approaches for optimal placement of distributed generation sources in power systems, IEEE Trans. Power Syst., Vol. 19, No. 4, pp. 2068-2076, November 2004] and Gozel et al. [Optimal placement and sizing of distributed generation on radial feeder with different static load model, Proc. of IEEE International Conference on Future Power Systems (EPS 2005), pp. 1-6, Amsterdam, The Netherlands, 16-18 November 2005] to verify the proposed method.