Improving Energy Efficiency in Agronomical Systems

Abstract

Increasing demand for agricultural products and production of resource constraints-especially the limitation of cultivable areas -have made the highest yield per unit area the main goal of agricultural producers. Agriculture is a system exhibiting high energy consumption and production. Since energy has a direct impact on the efficiency of crop production, a sustainable agricultural system needs to be analyzed in terms of its input and output energy to determine the total consumed energy of production per unit area. The difference between input and output energy determines energy efficiency of an agronomical system. Input energy requires being well analyzed to reduce energy consumption and increase energy efficiency. This paper reviews energy efficiency indices based on energy consumption during planting and harvesting. To enhance energy efficiency of agronomical systems, some strategies are discussed in detail, including using high quality seeds, minimum tillage systems, direct seeded rice, weeds control especially in irrigation canals and plant nutrition through agronomical management. Although some agronomical strategies -like complementary irrigation in dry land farming systemsincrease input energy, they increase crop yield. However, when output energy, resulting from the rise in crop yield, is higher than input energy, the system energy efficiency improves. Still, some inputs cannot be altered according to regional conditions which are often related to harvest stages operations.

Energy Flow of Watermelon Production System for Optimizing Energy Efficiency

“…used in planting of watermelon (kW) HLI= EQHL. HL [6] in which HLI is energy consumed by human in terms of MJ.ha -1 , EQHL is human energy equivalent in terms of MJ.h -1 and HL is the time of human labor in terms of ha -1 . The efficiency of watermelon planting system was measured by three indexes according to the following equations (3):…”

“…Due to the limitation of energy supply sources, the necessity of optimal use of energy has been revealed. However, research has shown that the higher productivity of agricultural ecosystems has only been accompanied by the help and increase in energy consumption in various production sectors, such as seeds, pesticides, chemical fertilizers, and fuel (5,6). In fact, the lack of optimal use of energy in agriculture in developing countries has created major limitations for the production of agricultural products, and thus, the realization of sustainable agriculture (7).…”