Sobradinho (BA) Floating Photovoltaic Platform - Challenges and Implementation Strategies

J. Bione Melo Filho, P. Sinval
Companhia Hidro Elétrica do São Francisco - Chesf,
Brazil

Keywords: floating photovoltaic plant, solar energy, hydroelectric power plant

Summary:

This paper aims to present an analysis of the methodology used to implement the floating photovoltaic system (step 1 MW) in the Sobradinho Hydroelectric Power Plant lake, as a result of the P&D+I project entitled "Solar Energy Exploration in Lagos of the Hydroelectric Power Plants". This study aims to evaluate the complementarity of photovoltaic solar generation with hydroelectric power, through the installation of floating photovoltaic solar power plants in the Sobradinho / BA (Chesf) and Balbina / AM (Eletronorte) hydroelectric lakes, focusing on factors such as: power generation capacity; economic gains; gain in reservoir water storage; social and environmental impacts; and opportunities for cost reduction. Both floating photovoltaic systems will take advantage of existing assets in the hydroelectric complexes (especially the reservoir and the electricity connection and transmission system), with the benefit of better use of these systems and a reduction in the costs of implementing the transmission of energy. In addition, an application of floating photovoltaic systems allows a better use of the available space in the reservoirs of hydroelectric plants, thus allowing the deployment of these systems on usable land. Application of this technology can also lead to a reduction in the level of water evaporation at the installation site and an increase in photovoltaic productivity due to the natural cooling of the system by the water surface. The benefits associated with the use of floating photovoltaic systems operating on water surfaces are verified by comparing these systems with equivalent systems in smallest scale installed on land near the floating system installation site. This allows the comparison of the behavior of photovoltaic modules operating under different conditions, with emphasis on the evaluation of the effect of working temperature. For several decades, hydroelectricity has been prominent in the Brazilian electric scenario and has been consolidated as the main source of generation in the country, being responsible for most of the service to the national energy market. However, the increasing environmental restrictions that have been unfavorably manifested to hydroelectric plants, are contributing to the reduction of their generation potential and, consequently, to an increase of the vulnerability of the Brazilian electric system. An example of this is climatic variations that, during prolonged periods of low rainfall, directly affect the generation capacity of these plants due to the reduction in the level of their reservoirs, which in turn leads to deficits in their energy production. To compensate for this reduction, there is the activation of thermal plants that, due to their high cost of operation and production, end up making the value of energy bills more expensive and also contributes to the increase of the greenhouse effect by releasing large amounts of polluting gases in the atmosphere. In this context, it is important and necessary to search for alternatives and measures that are able to mitigate the effects of these restrictions and, thus, contribute to the increase of the country's energy security and to minimize the environmental impacts caused by the emission of polluting gases.