Energy balance and energy economic analyses of rice production systems in Ayeyarwaddy Region of Myanmar

The status of energy balance and energy economics of irrigated and rain-fed rice production systems is studied and compared for highlighting the effect of farm size. Primary data were collected from 51 irrigated and 54 rain-fed rice farms in Northern Ayeyarwaddy Region, Myanmar. Farm classes were identified as small (< 2.5 ha) and large (2.5-25 ha). Energy estimates were calculated from actual amount of inputs and outputs and corresponding conversion factors. Results showed that the total energy inputs were 19,170.5 and 11,031.1 MJ/ha, respectively, in irrigated and rain-fed rice systems, while the total energy outputs were 104,162.7 and 65,033.5 MJ/ha in the two systems, respectively. Energy efficiency ratios, defined as output-to-input energy values, were 5.6 and 5.9 in irrigated and rain-fed rice production systems. Interestingly, the two systems were not statistically different for their energy efficiencies. Similarly, the energy efficiency ratios for different farm classes under both rice production systems were also not statistically different. Energy productivity and specific energy were 0.27 and 3.8 kg/MJ; 0.29 and 3.9 MJ/kg in irrigated and rain-fed systems, respectively. The energy benefit-cost ratio was higher in rain-fed rice (1.1) than in irrigated rice (0.9) system. Rain-fed system seems to have potential of further increasing yield through the increased yet appropriate use of energy inputs.