A revision of the tarification in the Brazilian electrical system based on the application of the network data envolpment analysis model.
Data envelopment analysis. Brazilian electric sector. Tariff. Efficiency.
Tariff Adjustments. Supply Chain.
The Brazilian electricity sector has shown different changes, since unbundling of
companies to the creation of the regulatory agency (Aneel - National Electric Energy
Agency), responsible for the economic regulation of the transmission and distribution
segments. However, Aneel apply charging policies separately between the segments that
make up the electrical system, not considering the relationship in the supply chain. In
this context, this paper aims to propose a new model of the Brazilian electric system
efficiency analysis in order to make the best-adjusted tariff review with the system
reality. The segments of the industry (generation, transmission and distribution) were
founded through a set of recurring variables in the literature to portray the processes
carried out in the electrical system at the national and international levels. The
conceptual model includes initially 12 variables divided into three dimensions: cost,
productivity and quality. The sample includes 94 companies, that consists in 16
generation companies, 28 electricity transmission companies and 50 distribution
companies. The Decision Making Units (DMU) were considered the paths starting in
generation to distribution, so that the sample totaled in 362 DMU's. In conducting the
research analysis, was developed a model to evaluate the electrical system using the
data envelopment analysis (DEA) to quantitatively identify the network efficiency level.
To be able to represent the complexity of the electrical system, a unique grouping model
was proposed and analyzed by Network DEA's model (NDEA) in three stages, each
simulating segments of the industry, for identifying the impacts between the processes
and causes of inefficiency. These stages of the network were evaluated for verify the
performance of the companies in each segment and validate the model of constant
returns to scale, through the classic models CCR compared to the NDRS used by Aneel.
From this comparison between the classic models, it has validated the use of constant
returns to scale model for sector analysis. The results of the NDEA model point to the
adequacy of the proposed method by performing the electrical system aggregate
analysis, by presenting more discriminatory results than classic models. Furthermore,
obtained that no path of the network has the three constituent companies efficient in its
entirety. However, it was possible to identify which links those companies should focus
their investments to achieve better performance and which networks are its benchmarks,
contributing to the management decision-making and the efficient planning of
companies. Finally, we identified the exogenous factors that influence efficiency, such
as geography and size, and then it is possible to obtain a more appropriate tariffing as
the reality of the sector, both benefiting consumers, as companies and government.