Incorporating large-scale renewable to the transmission grid: Technical and regulatory issues

Brazil presents a remarkable potential for the development of renewable energies. Besides large-scale hydro plants, the wind power plants, small hydros and cogeneration from sugarcane bagasse are the mainstream options. These sources have increased their participation in the country´s energy matrix due to their attractive characteristic such as smaller environmental impact and lower construction periods (in general less than 3 years), which is suitable in a context of an uncertain load growth, since it offers an attractive option and mitigates the associated risks. The development of these resources requires the availability of a transmission system sufficiently robust in order to allow the flow of the electricity produced by these resources. Because these plants are distributed geographically over a large (dispersed) area, their connection to the transmission grid is complex. In order to turn feasible the connection of these plants, a complex and integrated technical and regulatory scheme of planning and pricing of transmission-distribution networks was developed. The objective of this work is to present and discuss the technical and regulatory questions associated to the connection of renewables in the Brazilian power system and what has been proposed to address these issues.