Geração hidrelétrica, termelétrica e nuclear

Abstract

The electric energy problem T he debate on energy in the beginning of President Lula's second term in office became more intense, involving the Growth Acceleration Plan (GAP) itself, which was announced with great expectation to overcome the apathy in which the Brazilian economy had fallen more than a decade ago. Therefore, the success of GAP is important. Energy must not be a bottleneck.The first sign of the problems that are in the root of the current debate was given in the beginning of the president's first term by the so-called Study Group for the New Structure of the Electric Sector (Genese), created in 2003 to aid the Superior Council of the Eletrobrás System (Consise), made up by the presidents of the federal generation companies. At that time Consise was assigned an important strategic role within Eletrobrás, defining lines of action of its companies, which unpleased many people.The emergency problems that were indicated included the market decline after the 2001 electricity rationalization, which produced an energy surplus in the short term and pulled the price down at the spot market, where the generation companies sold that surplus. By order of the regulation applied by the government, from 2003 on the federal generation companies (that belong to Eletrobrás), such as Furnas, had their contracts with the distribution companies, such as Light and Eletropaulo, progressively cancelled. Therefore, they had to sell their energy at the spot losing revenues and reducing their investment capacity. To give an idea of what that meant, Furnas sold hydroelectric power to the distribution companies according to a contract at R$ 80/MWh, while at the spot it only reached R$ 18/MWh. Some of that energy at the spot served to substitute contracted energy from thermal power plants, that remained turned off, since the National System Operator wouldn't dispatch them if there was an adequate level of water in the hydroelectric power plants' reservoirs. However, those thermal power plants that were turned off received as much as R$ 130/MWh according to the contracts that they had with the distribution companies. Furnas continued to produce energy with almost 100% of its capacity, with half of it being paid by contracts for approximately R$ 80/MWh, and half at the spot market for R$ 18/MWh, which resulted in an average of R$ 49/MWh. At the time I voiced my dissatisfaction with that situation which gave Eletrobrás a huge loss.

Effects of Brazil's Political Crisis on the Science Needed for Biodiversity Conservation

“…Conservation of native vegetation around watercourses is known to be one of the most effective means of avoiding erosion and maintaining stream flows during drought periods, and to provide corridors and connectivity for the terrestrial fauna (e.g., Sekercioglu et al, 2015). The major urban centers of Brazil, where most of the GNP is generated, have suffered from a lack of water in the catchments of the major dams (Nobre et al, 2016) and the cost of energy to consumers is regularly increased because expensive, highly-polluting, thermoelectric plants have to be used to complement hydro-electric power provided by the dams (Rosa, 2007). Additionally, the losses of native vegetation in the Cerrado savanna region in Central Brazil are altering the water balance through increased evapotranspiration and diminishing the capacity for water storage (Oliveira et al, 2013).…”

A construção de uma usina hidrelétrica e a reconfiguração das identidades dos ribeirinhos: um estudo em Salto Caxias, Paraná

“…According to Rosa (2007) the building of a hydroelectric plant initially requires a confluence of rivers and a geographical relief which allows for the existence of waterfalls to produce electricity. In order for this to occur, a dam or a reservoir must be built to contain the water.…”

Modelagem Computacional de uma Blindagem de Nêutrons Utilizando Métodos Determinísticos

“…destaca-se a produção da energia elétrica a partir de reatores nucleares, tema bastante relevante na Engenharia Nuclear [3]. Nesse trabalho propõe-se a utilização da equação de transporte linearizada de Boltzmann como modelo matemático para descrever os problemas de blindagem de nêutrons, resolvendo-se, então, um problema aproximado de blindagem.…”