ANÁLISE TÉCNICA E ECONÔMICA DE COLETORES SOLARES DE BAIXO CUSTO E CONVENCIONAIS UTILIZADOS PARA AQUECIMENTO DE ÁGUA DE BANHO

Abstract

Solar collectors named “non- conventional” use cheap material, generally plastic material or similar, that makes possible the cost reduction. These collectors have been offered in the market for domestic hot water application such as showers. However, these collectors show as disadvantage the fact that they heave lower thermal efficiency and lower life time compared to conventional collectors. The solar collectors used for domestic hot water and swimming pool water heating are generally evaluated by their thermal efficiency that is converted in specific monthly energy production, not considering an economical analysis that take in account th e initial investment necessary for the equipment acquisition as well as its life time. This work presents thermal and economical analyses for two non conventional plastic solar collectors and four conventional (ranked “A” and “B”) solar collectors. Data of these collectors were obtained from their manufacturers and used in our thermal and economical analyses. Having as the goal to verify better the performance of one plastic collector, we have manufactured one prototype for testing in our laboratory. Also it was constructed a ring test for collectors testing. Economical analyses have been conducted considering different sceneries related to the life time of the collectors in order to obtain different economical indexes. One of the plastic collectors showed economical indexes comparable to those of the conventional collector ranked as “A”. The collectors ranked as “B” showed higher indexes than those collectors ranked as “A” An economical index named “Index of Merit” has been proposed for comparative analyses of collectors taking in account three variables: the collectors specific energy production, the life time and the initial cost.