Reliability benefits of distributed generation as a backup source

The power system especially at the distribution level is prone to failures and disturbances due to weather related issues and human errors. Having distributed generation (DG) as a backup source ensures the reliability of electric power supply. Therefore, distributed generation is expected to play a key role in the residential, commercial and industrial sectors of the power system. In this paper, the value of DG installed as a backup generator is quantified in terms of its contribution to the reliability improvement of a residential distribution network. The reliability improvement is measured by reliability indices that include SAIDI, CAIDI and ENS. In addition, the value of placing DG at various distances from the substation, as well as the impacts of installing a large-scale DG vs. several small-scale distributed DGs, are presented. The research findings are expected to be useful to electric utility companies in evaluating the reliability benefits of DG of various sizes and penetration levels installed at various distances from a distribution substation.