Impact of Economic Regulation on Distributed Generation Integration in in Electricity Distribution Grids

Abstract

Energy policies in favor of a larger adoption of renewable energy sources for electricity production purposes and the significant progress of several renewable technologies are among the main drivers behind an increasing integration of distributed generation (DG) in distribution networks. DG affects distribution network planning and operation and, consequently, higher or lower network costs than in a traditional passive network scenario arise. Two main complementary tools for an efficient integration of DG have been identified in this thesis: (i) a sound economic regulation of Distribution System Operators (DSOs) for taking into account DG-driven potential costs and accordingly remunerating DSOs, and (ii) network tariff design, in order to allocate network costs and re-distribute potential benefits to different grid users. Distribution economic regulations vary from country to country with grid characteristics and regulatory customs. In order for Regulators to promote the integration of DG units according to policy objectives, the potential impact of DG on the different distribution costs needs to be analyzed and quantitatively assessed: in this thesis, these objectives are achieved by using a novel model that combines the technical characteristics of distribution grids with the regulatory details specific of each regulation. Once computed, DSOs' total allowed revenue is allocated to different users' categories according to the adopted tariff structures. This thesis focuses on the challenges arising within the traditional paradigm of distribution tariff design when an increasing amount of DG is connected to the grids. In particular, the consequences of DG exemption from distribution tariffs and the application of load-tailored tariff schemes to DG are investigated, both from a qualitative and quantitative point of view; cross subsidies between consumers and DG owners are computed by applying a cost causality principle.