This document discusses optimal placement of distributed generation in distribution networks. It introduces different types of distributed generation and outlines the advantages of distributed generation integration. It then discusses various approaches for optimally placing type 1 distributed generation, which can only inject real power, to minimize power losses and improve voltage profiles. Particle swarm optimization is applied to determine the optimal size and location of type 1 distributed generation in 33-bus and 69-bus test systems. The document also considers optimal placement of type 1 distributed generation and capacitors together in order to compensate for reactive power losses.