A novel approach for analyzing the food-energy nexus through on-farm energy generation

To find a balance between food and energy security, this research presents the design of an energy self-sufficient farm in electricity, heat and bioethanol, which is produced by energy crops and agricultural residues. The farm proposed is evaluated by two models: Land Optimization and Cost Optimization. Due to the food–fuel debate over land and the detriment of food security, this research proposes utilizing the current abandoned land and increasing the food self-sufficiency ratio (FSSR) of the crops analyzed (rice, wheat and maize). The farm is optimized for several food and fuel demands, with a maximum farm unit size of 100 ha. The result is a myriad of farms of different sizes, each optimized for a certain demand. Subsequently, the amount and variety of such farms are optimized maximizing the food and fuel produced for each city of the case study (Miyagi Prefecture, Japan). The results suggest that the establishment of energy self-sufficient farms in the abandoned land can stimulate the biofuel industry and increase food security simultaneously. The FSSR of maize and wheat can be improved in approximately 10–25 and 7–9 %, respectively. The estimated bioethanol potential is 3.2–3.8 ML. Additionally, a surplus of electricity and heat, approximately 61–65 GWh and 60–165 MJ, respectively, is obtained. As the Land Optimization model proposed is sensitive to crop yields, a simultaneous evaluation is recommended. The results also suggest that the farms must be larger than 8 ha to achieve self-sufficiency; therefore, the policies involved need further evaluation.