Comparison of energy consumption in agricultural cultivation and hydropower generation from irrigation reservoirs.

Abstract

The introduction of small-scale hydropower generation in irrigation reservoirs is being promoted in order to realise a sustainable society. When irrigation reservoirs are used for purposes other than agriculture, it is necessary to evaluate the effects and impacts of other uses. The amount of hydropower generated by irrigation reservoirs across Japan remains unknown because it is difficult to observe and estimate the flow conditions over large areas and large numbers of irrigation reservoirs. This study aimed to assess the potential use of hydropower from irrigation reservoirs from an agricultural perspective by estimating the amount of hydropower generated by irrigation reservoirs across Japan and comparing the amount of hydropower with the energy consumed by paddy rice cultivation. The top five prefectures with the highest proportion are Kochi (92.1%), Hyogo (60.8%), Kagoshima (22.6%), Wakayama (21.9%) and Miyazaki (21.3%) prefectures, where hydropower can provide the energy needed for agricultural activities other than drying, harvesting, ploughing and soil preparation. In prefectures with high hydropower generation, hydropower from irrigation reservoirs can provide energy for all agricultural activities, contributing to sustainable energy supply and agriculture.