Sahr Marvin Bockari-Gevao, Wan Ishak bin Wan Ismail, Azmi Yahya, and Chan Chee Wan

pp. 819 - 826

Abstract

Sufficient energy is needed in the right form and at the right time for adequate crop production. One
way to optimize energy consumption in agriculture is to determine the efficiency of methods and techniques
used. With the current increase in world population, energy consumption needs effective planning. That is,
the input elements need to be identified in order to prescribe the most efficient methods for controlling them.
This study was undertaken in order to determine the direct and indirect energy consumption of field operations in a lowland rice production system of Malaysia. Field time, fuel and other energy requirements were
measured for the tillage, planting, fertilizing, spraying and harvesting operations performed. Energy analysis
carried out revealed the highest average operational energy consumption was for tillage (1747.33 MJ ha^-1)
which accounted for about 48.6% of the total operational energy consumption (3595.87 MJ ha^-1), followed by harvesting (1171.44 MJ ha^-1, 32.6%) and planting (562.91 MJ ha^-1, 15.7%). Fertilizing and pesticide
spraying did not make any significant contributions to the operational energy consumption. Based on energy
sources, fuel was the main consumer of direct energy with 2717.82 MJha^-1 (22.2%), and fertilizer recording
the highest indirect energy consumption of 7721.03 MJha^-1 (63.2%). Human labour, pesticides, seeds and
indirect energy for machinery use had marginal importance, contributing only 0.2%, 0.6%, 6.8% and 6.9%,
respectively to the total energy consumption (12225.97 MJha^-1). Average grain yield was 6470.8 kg ha^-1,
representing energy output of 108321.75 MJha^-1, that is, 96095.78 MJ net energy gain or 8.86 MJ output per
MJ input. Energy input per kilogram grain yield was 1.89 MJkg^-1. The results of the study indicate energy
gain in the lowland rice production system of Malaysia.