Analysis of solar photovoltaic energy potential in Brazilian hydroelectric reservoirs through floating panels

Abstract Sustainability, a concept used to exploit natural resources without harming future generations, is being applied to power generation. In Brazil, the main source of electric energy comes from hydroelectric plants, due to abundant water resources. However, the implementation of these plants causes irreversible impacts on the environment and society. On the other hand, the impacts caused by photovoltaic panels are considerably smaller in the construction phase and zero in the operation phase. This article describes the impacts generated by hydroelectric power plants and gives an overview of the power generated by floating photovoltaic panels using 10% of the area of the reservoirs of the largest hydroelectric power plants in Brazil. The results demonstrate a better efficiency of the photovoltaic panels in the water, which cools them, increasing their efficiency. Furthermore, photovoltaic panel power generation amount is higher than compared the annual power generation of three out of four hydroelectric plants analyzed. In addition, adding solar energy to the reservoirs would save infrastructure costs, considering that energy can be made available through substation infrastructure and existing power transmission systems.

Richness and structure of ant assemblies (Hymenoptera: Formicidae) in Atlantic forest in southern Brazil

ABSTRACT Ant diversity is influenced by the structural complexity of the environment. Ants are thus an ecologically important group due to their potential to serve as indicators of environmental quality. The objective of this study was to evaluate ant diversity in areas with different land use histories and thus, within different stages of regeneration in the Permanent Preservation Area of the Foz do Chapecó Hydroelectric Plant reservoir. Ant assemblies among sample sites were compared using rarefaction analysis, and estimated richness, frequency of occurrence, and relative abundance were calculated. Associations between species and sample sites were evaluated using Principal Component Analysis (PCA). We identified 55 species in total from 24 genera, distributed among seven subfamilies. Eight species had positive associations with sample sites. Estimates indicated that ant richness may be up to 21.4% greater than that observed. This study presents an inventory of species capable of colonizing environments undergoing natural regeneration processes, and aids our understanding of ecological recovery dynamics in protected areas near hydroelectric plant reservoirs southern Brazil.

Environmental impact and seroepidemiology of HTLV in two communities in the eastern Brazilian amazon.

The objective of this study was to detect antibodies for human T lymphotropic virus (HTLV) in subjects residing in two communities located in the eastern Brazilian Amazon and on the shores of the Tucuruí hydroelectric power plant. A total of 657 serum samples were analysed using an enzyme-linked immunosorbent assay with an anti-HTLV antibody (Symbiosis™, São Paulo, Brazil), demonstrating a virus prevalence of 4.7%. Most individuals with HTLV were aged over 30 years (P = 0.013), were unmarried (P = 0.019), resided in the area for more than 10 years (P = 0.001), had a low level of education (P = 0.015), and had a family income of up to $305 (100%). In contrast, there was no significant association between infection and sex, city of birth, haemotransfusion, or previous surgery. The prevalence observed in these communities suggests that the residents should be concerned about HTLV infection, and that some areas may become endemic for HTLV.