Energy Efficiency of Intensive Rice Production in Japan: An Application of Data Envelopment Analysis

Kiyotaka Masuda

doi:10.3390/su10010120

Abstract

Intensive rice production has contributed to feeding the world’s growing world population, but it has also increased fossil energy consumption. This paper examines the effect of increasing the scale of rice farming on the energy efficiency of intensive rice production in Japan. A data envelopment analysis (DEA) approach is used to calculate energy efficiency scores and identify operational targets. A window analysis technique is applied to the 2005–2011 statistical data, with nine scales of rice farming, ranging from <0.5 ha to ≥15 ha. Six energy inputs (fossil fuels, electricity, chemical fertilizers, pesticides, agricultural services, and agricultural machinery) and the weight-based rice yield are selected as the DEA inputs and the DEA output, respectively. The results show that the energy efficiency scores range from 0.732 for farms of 1 ha to <2 ha, to 0.988 for farms ≥15 ha. Overall, increasing the scale of rice farming in Japan improves energy efficiency because of a great reduction in the energy consumed per unit area by agricultural machinery and agricultural services. These findings suggest that increasing the scale of farming is an effective way to enhance the energy efficiency of highly mechanized rice production in developed countries, such as Japan.

Highlights

Fossil fuels, which are nonrenewable resources, are indispensable to modern agriculture, contributing to impressive yields in crop production [1]
data envelopment analysis (DEA)-based energy efficiency indicators for intensive rice production in Japan were evaluated in accordance with the scale of rice farming
DEA window analysis was applied to panel data based on scale observations of rice farming that were collected from MAFF data for 2005–2011

Summary

Introduction

Fossil fuels, which are nonrenewable resources, are indispensable to modern agriculture, contributing to impressive yields in crop production [1]. They are primarily consumed in the manufacture and operation of agricultural machinery and the production and application of chemical fertilizer [2]. Rice is a staple food for more than half the world’s population, with Asian regions accounting for the bulk of its production [3]. In Japan, where rice has long been the traditional staple food [4], rice production is highly mechanized compared with production in developing countries and it depends greatly on inputs produced using fossil fuels, such as chemical fertilizers [5]. Japanese rice farms have traditionally been small (the average size is 1.9–2.4 ha according to the Ministry of Agriculture, Forestry and Fisheries of Japan (MAFF) [7]), they are steadily growing in size as a result of agricultural policy reforms, including the relaxation of farmland regulations [4]

Methods

Results

Discussion

Conclusion