Modelling and Sensitivity Analysis of Energy Inputs for Rice Production in Nigeria

The influence of energy inputs and form of energy on the output level for rice production in Nigeria was investigated. The sensitivity of energy inputs was estimated using the marginal physical productivity (MPP) method and partial regression coefficients on rice yield. Energy related data for two (2) growing seasons were collected in nine (9) rice farms. The farms consist of three (3) small, medium and large farms, respectively. Data were obtained through field surveys, direct measurements, interviews with farmers and structured questionnaires. Standard equations were used to evaluate the energy requirement for each defined unit operations. Econometric model evaluation showed that nitrogen and phosphorus fertilizer and biological (seed) energy were the most important energy input that influences energy output. The elasticity of nitrogen, phosphorus fertiliser and biological energy on the output were 0.86, 0.44 and 0.13, respectively. While, mechanical, thermal and manual energy were 0.08, 0.050 and 0.026, respectively. The coefficient of indirect energy and direct energy were 0.90 and 0.05, respectively. Sensitivity analysis results indicate that additional use of 1 MJ of phosphorus fertiliser, manual, biological (seeds) and machinery energy would increase rice yield of 6.36, 1.08, 1.05 and 0.82kg, respectively. Energy inputs and patterns of energy consumption in rice production was modelled. The models adequately predicted the energy inputs and output for rice production.