Studies on Energy Input in System of Rice Intensification Method of Rice Cultivation

System of Rice Intensification (SRI) is a rice cultivation method that intensively control and manage macro and micro nutrients as well as irrigation. This paper quantifies and compares the energy uses of SRI and conventional rice cultivation systems. The study was conducted at some SRI's experimental plots in the districts of Sleman, Kulonprogo, and Bantul, the province of Yogyakarta. The calculation of the energy was based on the farmers' work schedule, the time required for each operation, the number of laborers, machines, tools, fuel, and all materials and inputs used. The result shows that SRI method consumed 35% less energy to conventional rice cultivation. Energy inputs from seed, water, fertilizer and pesticide were significantly reduces. However, there was higher input of human energy due to composting, land preparation and weeding operations. The specific energy of SRI method was 1.96 MJ ha(-1) lower than conventional method of 4.43 MJ ha(-1). In the SRI method, 56.2 % of energy consumed was classified as direct energy and 43.8 % was indirect energy. The SRI method used 61.9 % of renewable energy and 38.1 % of non-renewable energy. The working efficiency in composting and weeding operations should be improved in perspective of machine and tools to reduce the use of human energy.