Growth in energy demand is more than the energy production due to various reasons like industrial growth, rapid urbanization, increasing affordability of electric gadgets, etc. The integration of existing grids with renewable energy sources provides economical, sustainable and efficient power distribution, and this allows to control the greenhouse effect. The reduction in power loss and voltage profile improves the distribution system, which can be done by using some techniques, such as feeder or network reconfiguration, VAR compensation with capacitor banks, and Distributed Generation (DG). DG is a localized small scale generation installed in the distribution network capable of injecting active power and providing limited reactive power support, reduced distribution losses, improved voltage profile in the system, hence, improving the quality of the power. The significant process is to improve the power quality of the system and this system is used to find the size of the DG unit and their suitable locations of the system. In this paper, IPSO and a new gradient free, meta-heuristic, population based algorithm called BAT Inspired Algorithm, are used to evaluate the optimal size and location of DG units. Distributed load flow is carried out for 33-bus and 69-bus systems to obtain power losses and voltage at each bus. Optimization techniques like IPSO and BAT algorithms are considered for the optimal placement and optimal sizing of Distributed Generators in radial distribution system by multi-objective optimization approach has been discussed. The practical application and efficiency of this method is determined by using two test systems (33 and 69-bus). The proposed methods are carried out using MATLAB.