In this paper, a multi-objective analytical method to evaluate the impacts of optimal location and sizing
of distributed generation is presented. This method is based on an analysis of the exact loss formula and
continuous power flow in a radial distribution system. Based on two methods of analysis, power loss
and weakest voltage buses and lines are calculated and then the optimal size of distributed generation
is determined. After that, by considering the minimum power losses and the maximisation of voltage
stability, the proposed index determines and ranks positions to decide the optimal distributed generation
location in the system. This method allows us to find the best places and size to connect a number of
distributed generation units by optimising the objective functions. The simulation results were obtained
using a 33-bus radial distribution system to determine the location and size of the distributed generation
units. The results show the effectiveness of voltage profile improvement, loading factor improvement
and power loss reduction. Further, the problems of a single objective function and the placement of the
distributed generation unit using analytical methods are solved by the proposed approach.