The reliability and security of an electric power supply have become pivotal to the proper functioning of modern society. Traditionally, the electric power supply system has been designed with the objective of being able to adequately meet present and future demand, with efforts to maintain supply reliability being focused primarily on the supply side. Over the decades, however, the value of demand-side management—efforts focused on enhancing the efficient and effective use of electricity in support of the power system and customer needs—has been widely acknowledged as being able to play a greater role in ensuring that the key objectives of power system operation are satisfied. This article presents a study of demand-side management and opportunities for incorporating it into network planning as an effective means of addressing supply capacity constraints in the South African electric grid. The main drivers, benefits and potential barriers to the effective implementation of demand-side management are examined, along with the main enabling technologies. The key finding of the study is that the effective integration of demand-side management into network planning requires a shift from the traditional network planning approach to one that is more suited to fully exploiting the flexibility resources available on the demand side of the network.

Electric power distribution systems have been undergoing a transformation that can be attributed to factors such as the deregulation of the electric power supply industry, growing public concern over energy security and the environmental impact of energy generation and utilization, and technological advancements that have given impetus to concerted efforts to modernize the power grid in the framework of smart grid initiatives. The traditionally passive distribution network is increasingly becoming active due to the steady increase in the amount of distributed energy resources being integrated into the network. This has, in turn, given rise to a higher need for flexibility resources that can be used to handle the increased uncertainty caused by stochastic and intermittent distributed resources, such as variable renewable power generation. The provision of demand-side flexibility has largely been the purview of large industrial and commercial energy consumers. This article discusses the role that the aggregator can play in facilitating the provision of flexibility resources by small-scale consumers and prosumers and presents a case study on small-scale renewable generation and residential demand forecasting, which form an integral part of demand flexibility aggregation.