Net energy gain efficiency, a new indicator to analyze energy systems, case study: Comparing wheat production systems

Abstract

Energy indicators are used to assess energy status in production systems via studding the energy consumption and efficiency and also to compare the production systems with each other. Common energy indicators cannot comprehensively compare different energy systems. The goal of the present study was to introduce a new indicator namely net energy gain efficiency to provide a comprehensive indicator for comparing the energy systems. After gathering the required information about the inputs and outputs of 70 dryland and 30 irrigated wheat production systems using the questioner method in Ilam, Iran, the values of the indicator were calculated by developing a new formula. Also, energy contents, forms, and other indicators were calculated for both systems using custom formula. The value of the net energy gain index of irrigated and dryland wheat farms were 111.68 and 49.83 GJ ha−1, respectively, while the value of the net energy gain efficiency of the irrigated and dryland wheat production systems were 5.37 and 4.12, respectively. The net energy gain efficiency indicator allows a comprehensive comparison of different systems compared to the common net energy gain index. The net energy gain efficiency is recommended to be applied for comparing different production systems in the future.