Encontro de Energia no Meio Rural

Abstract

OCACIA, Gilnei Carvalho, DUARTE, Humberto Amaral, MARTINS, Franco Muller et al. Uso racional de energia em estações de bombeamento de água para irrigação de arroz. In Procedings of the 4th Encontro de Energia no Meio Rural, 2002, Campinas (SP) [online]. 2002 [cited 26 April 2024]. Available from: <http://www.proceedings.scielo.br/scielo.php?script=sci_arttext&pid=MSC0000000022002000200063&lng=en&nrm=iso> .

138 facilities pumping used for rice irrigation were analyzed in the region Fronteira Oeste of Rio Grande do Sul. The installations were classified by discharge height level: smaller than 10m; between 10 and 15m; between 15 and 20m; between 20 and 25m; and, larger than 25m. The possibility at a large energy conservation was verified. It was verified the requested net power of 4155 kW representing 47,44% of the installed power. The total power installed in the analyzed systems is 8757 kW. Losses main reasons: badly dimensioned piping; use of low efficiency pumps; maintenance lack; over dimensioned pumps; badly installed pumps; and, low power factor. The most efficient installations are those that present larger discharger height level. That is a consequence of the use of centrifugal pumps (they present better efficiency in discharger heights above to 10m) and to the fact that they present a larger demand of net power, forcing the farmer to be very careful with its installation. Where the heights of pumping are smaller, due to privileged topographical situation, there is a smaller concern with the costs. To make possible the comparison among systems with different water discharge heights, it was established a power index for unit of area and of height (W.ha^-1.m^-1). It indicates the demand for the irrigation of one hectare of farming, for one meter of water elevation. The efficient system should present values smaller than 30 W.ha^-1.m^-1. The values are between 25 W.ha-1.m-1 and 100 W.ha^-1.m^{-1 in the analyzed systems,.}

Keywords : Bombeamento; irrigação; arroz.