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Brazil has an energy system with a hydrothermal characteristic that interconnects consumers and generators covering 98% of the demand for energy supplies. Most of the plants are concentrated in the southeast region, where the largest consumers and the largest population concentration are located. The expansion of this system, considering the hydroelectric contributions, will occur exploring the potentials located in the Amazon region. This analysis paper shows that the variations imposed by climate changes on some climatological variables create significant uncertainties about the power generation forecasts of the hydroelectric power plants to be installed in the Amazon, thus compromising the financial economic feasibility of these enterprises and also possibly compromising the expansion plans of the Brazilian energy system. The methodological approach uses information from various climate change scenarios and compares those with historical hydrological patterns and generation information. By exploring the characteristics of a large-scale hydrothermal system with high dependence on water resources, this paper provides valuable insights on how energy policy would address hydroelectric vulnerabilities and climate change. This analysis is focused on the Brazilian case but reveals important issues related to systems with hydro thermal characteristics. [ABSTRACT FROM AUTHOR]

Abstract The paper aims to discuss the adaptation of a brazilian social housing project to the Passive House standard, by defining the thermal envelope construction fabric for different climates of southern Brazil, from a base line according to the Brazilian performance standard. The study was developed in 4 steps, where a numerical model was set up and runned in a transient regime, using EnergyPlus® software. In the first step, the thermal and energy performance of the reference base model was assessed. In the second step, a sensitivity analysis was performed, varying the thermal envelope parameters of the building case study, in order to satisfy the minimum performance of the classification level A, according to the Brazilian Energy Efficiency Regulation (RTQ-R). In a third step, the external envelope of the building was optimised, through a multi-objective evolutionary algorithm. In a last step, the numerical model defined according to the Passive House standard was optimised, in order to obtain optimal solutions. Thermal and energy performance and economic viability of the solutions were analysed. Solutions attending to RTQ-R presented additional investment between 26% and 27% and solutions attending to Passive House standard presented additional costs of 39% and 42% for the three bioclimatic zones. Highlights • An optimisation methodology for Passive House design is presented. • An evolutionary multi-objective algorithm is used for thermal building simulation. • Different bioclimatic zones in Brazil are investigated. • Energy performance and thermal comfort of the buildings are significantly improved. • The Passive social interest housing is economically viable for bioclimatic zone 2. [ABSTRACT FROM AUTHOR]

Abstract: In several countries biodiesel blending programs have been implemented looking for reduction in fossil fuel dependence and environmental benefits, including climate change mitigation. The current global biodiesel production, from different fatty raw materials, reaches about 6 billion liters per year and represents 10% of whole biofuel production. Nevertheless, in many cases the actual advantages of biodiesel production and usage are not clearly evaluated. Essentially, the feasibility of biodiesel production can be determined by its efficiency in solar energy conversion, as indicated by agro-industrial productivity and energy balance parameters, which expresses a relative demand of natural resources (land and energy) to produce biofuel. Taking into account the Brazilian conditions, in this paper an assessment of biodiesel production is presented, comparing four different productive systems. According to this evaluation, soybean and castor are limitedly feasible, whereas tallow and palm oil represent more suitable alternatives. The selection of an efficient productive system is crucial for the rationality of biodiesel production. [Copyright &y& Elsevier]