Avaliação por simulação computacional de Sistemas de Aquecimento Solar para uso em chuveiros em Habitações de Interesse Social no extremo sul do Brasil.

Abstract

With the oil crisis in the 70’s and discussion of topics on environmental degradation and climate change on the planet, renewable energy came to be seen as solutions to supply the needs of domestic and industrial energy consumption. Solar energy is presented as a clean and inexhaustible source that could provide an alternative to reduce the use of non-renewable energy. In Brazil, the energy crisis peaked with the 2001 blackout. The shower, because its concentration of use in the late afternoon and early evening, was identified as one of the villains in the contribution of increased the peak in the demand curve, resulting in violations in the pattern of distribution of electricity. The shower is also present in 98.6 % of households in southern Brazil and is responsible for 25 % of residential electricity consumption in this region, burdening families with low incomes. Previous studies have demonstrated the effectiveness of the combined use of Solar Heating Systems (SHS) and electric showers with adjustable power for all regions of the country. Surveys show that only 6.1 % of the population of southern Brazil would be predisposed to replace electric heating systems for solar. This rejection can be attributed to low solar radiation and low temperatures in the cold periods of the year, in addition to high investment amount for acquisition of the systems. In this work, two compact SHS were modeled in the computer simulation program TRNSYS. Using climate data of Pelotas/RS (Latitude 31° 46' South), were simulated different profiles of shower using and different models of supply water temperature of SHS. By determining the Solar Fraction obtained by SHS, was possible to know the Electricity Saving for the users and make the financial analysis of return on investment for the acquisition of systems. Through a scenario of 420 residential units, the impact on reducing peak of the demand curve was evaluated. When determining the energy consumption taken from this period, was possible to quantify how the adoption of SAS could improve quality in power distribution and postponing investments in increased the capacity by the concessionaire. (State Electricity Company) On average, the solar fraction obtained in the simulations was 73.1%, resulting in an average annual savings of R$ 568.58 for users. This economy showed that the average return on investment occurs in the 4th year of use, on o 100 units scale. The average removal of consumption in the peak of the demand curve of 0.294 MWh, all results can be considered satisfactory.