Inclusion of renewable energy sources in the traditional grid encourages decarbonization and enables technology enhancement for better operation in the distribution system. Non-conventional sources penetration is increasing day by day globally to replace the fossil fuel based generation and save the environment. The solar and wind power generation share is increasing and there is need to decide their optimal placement and the sizes in the grid. In this study the main objectives are (i) Optimal capacity of renewable energy sources (RES) is obtained to minimize the power generation cost from conventional sources, (ii) optimizing the cost of RES, (iii) optimal allocation of hybrid Solar-Wind based DG. In this paper, the 24-h load demand data of IEEE 33 bus is considered with residential, commercial, and industrial load demand. The hybrid Solar-Wind based DG sources are integrated in IEEE 33 RDS and optimization is carried out using GAMS. The optimal location and sizes of renewable energy sources are obtained by minimizing the generation cost of the conventional and non-conventional energy source.