Use of solar energy for electric power generation and water heating in sustainable buildings in the state of Parana-Brazil considering future scenarios of global climate change

Abstract

The Sun is the primordial and indispensable component for the maintenance of life on Earth because it is the main source of energy of the planet. Considering the geographical position of Brazil and its mainland, Brazilian cities present great potential for the use of solar energy as a source of renewable energy, which provides a reduction of impacts to the environment caused by the exploitation of natural resources. Buildings are responsible for half of the country's electricity consumption and in addition, regional changes caused by climate change can also influence the generation and final energy consumption, since most of the risks and consequences of these changes are concentrated in urban areas. With this prelude as a motivation, this research aimed to estimate the potential of photovoltaic solar energy and solar energy for heating water in buildings in the State of Paraná, considering scenarios of climate change. Thus, four empirical models of solar radiation estimation were evaluated from air temperature data. Since the performance of the models was evaluated through the appropriate statistical indices, two of these presented the best results for localities in Paraná. In order to estimate the electric energy produced by the photovoltaic system, as well as by the solar heating system for a hypothetical single family dwelling in present and future conditions, impacted by climatic changes, daily climatological data of global solar radiation and air temperature were used, as well as modeling for systems. For the simulation of future climate scenarios, the model PGECLIMA_R was used, which is a computational tool for stochastic generation of daily climate data. In the evaluation of the results, statistical methods such as Analysis of Variance (ANOVA) were used, with comparison of means (Tukey test) and Kruskal-Wallis test, multiple comparison by Dunn method. The results pointed to annual indices of 98% service of the photovoltaic system scaled in all the analyzed locations. In the evaluation of the performance of the solar heating system, which estimates by the F-Chart method the annual solar fraction or percentage of energy demand that is covered by the system, based on the monthly average solar radiation incidence, it was verified that all localities present annual values of solar fraction between 82.4% and 129.8%, values considered very good for this purpose. Therefore, in view of the results found, it was concluded that the State of Paraná has favorable climatic conditions for the installation of solar energy systems, both photovoltaic and solar water heating, even taking into account possible changes in the the end of the 21st century.