AVALIAÇÃO DE ECONOMIA PARA DIFERENTES CAPACIDADE DE CISTERNA PARA UMA ESCOLA TÉCNICA DA REDE FEDERAL

The use of rainwater brings several advantages from an environmental and economic point of view. In the design of the technical project we can highlight the capacity of the reservation tanks. This should have an efficiency (volume able to meet demand over time) to an initial investment and operating costs compatible with the generated economy. In this sense, the present article aims to present the results of the monitoring, in a year, of the drinking water and rainwater consumption of a technical school of the Brazilian federal network, located in the city of Sapiranga (south of Brazil), after the implementation of improvements in the existing system (cistern with capacity of 10 m). A comparative simulation (consumption and economy) for different tank volumes is also presented, considering: (a) the situation before the implementation of the improvements (half the capacity 5 m), and (b) an ideal volume obtained by different methodologies 20 m). As a result, there was a real economy around one third (32.06% in terms of consumption and 30.23% in financial terms) and a real efficiency of 79.2%. In the simulations, a consumption savings of 20 m and 5 m, of 38.90% and 25.79% respectively would be obtained; a financial savings of 36.47% and 24.77%; and an efficiency of 100% and 61.2%, respectively.