Impacto de centrais eólicas no mercado de energia elétrica

Abstract

The significant growth of electricity load mainly at developing countries demands investments in generation, transmission and distribution. The recent reorganization of the electrical sector promoted in diverse countries had as main landmark the introduction of the competition and in parallel the attraction of private capital to foment the necessary investments. In the Brazilian case, it has a trend to expand more the hydro potential because of the inherent costs, leaving for a second moment other power plants including the thermal generation. Despite this trend, an opportunity was open for alternative sources through the creation of the PROINFA (Program of Incentive to Alternative Sources of Electric Energy), instituted by the Law n.º 10,438, of April, 26 of 2002 and revised by the Law n.º 10,762, of November, 11 of 2003, stimulating the installation amongst others, of wind generation, that are well developed in many countries.

Given the evaluated wind potential in the Brazilian northeastern region and the incentives created by the PROINFA program, it is foreseeing a rapid growth of wind power generation in the Brazilian electrical system. As the hydraulic generation represents the predominant power source in the Brazilian electrical system and the operation of them is performed by a centralized optimum dispatch, this work presents a methodology to incorporate these wind farms in the existing optimization computational programs. Moreover, given that, in the Brazilian energy market, the "spot" price is defined as the marginal cost of operation and it is obtained by such programs, this work also analyze the impact of such farms on the electricity market prices. An analysis of the correlations between the hydrological series and wind series is developed and applied to optimization software using of Benders’ decomposition technique for the definition of the hydrothermal dispatch. In this software, developed in Matlab, an insertion of wind power generation is considered in optimization process and the "spot" prices are calculated for the northeastern region electricity market. The results show that the insertion of the wind generation for this region presents considerable energy payoffs which influence the energy prices. Still, in this software, "cluster" techniques are used for the hydrological series in order to group and to analyze different hydrological behaviors.