Sustainability of Brazilian energy tariff model under a high penetration scenario of distributed photovoltaic microgeneration

摘要

In Brazil, low voltage consumers are charged by the Use of the Distribution System the Energy Tariff and the sector charges, composing the monomial residential tariff. The Tariff for the Use of the Distribution System includes the values referring to the costs with the Transportation of Energy from the generation to the distribution. In this work, the variable Cost of Transmission was defined, which covers costs related to the Transmission Use Tariff and the Transmission Usage Amount. However, when considering that part of the consumers becomes a microgenerator in a distributed microgeneration scenario, part of this Transmission Cost estimated as receivable by the distributor is not realized, therefore, during some hours of the day in which the consumer is able to generate electric energy through solar irradiation, the consumer stop to pay for the electricity, and therefore, for that cost of energy transmission that the distributor planned to receive. The results of this work show that maintaining the current tariff model, as there is greater penetration of distributed generation among residential consumers, the greater the difference between the Transmission Cost values planned and paid by consumers to the distribution network operator. In this way, it can be concluded that the tariff system in force in Brazil creates a situation of economic imbalance for the distribution network operator as the penetration of distributed generation increases. It is estimated that, probably, all consumers would have extra tariff adjustments to maintain the balance between tariff modality and the remuneration of Transmission Costs.