Can agriculture provide us with both food and fuel?

The objective of this study was to answer the question: "Can agriculture provide us with both food and fuel?"

To do this, a database of the global agricultural primary production and its energy content was constructed. The database was further used to estimate losses within the agricultural system, as well as possible biofuel production. Moreover, the basic conditions for agriculture and plant growth were studied in order to assure sustainable scenarios of biofuel production. The future expansion potential of agriculture is discussed.

The energy available for food was found to be 9370 TWh if rest products from processing are considered edible and 7320 TWh if they are considered inedible. Assuming a food demand of 2500 kcal per day and person for the 6.7 billion world population gives a global food demand of 7092 TWh.

To be able to estimate the potential of biofuel production using feedstock from agriculture, the energy exchange was calculated for different crops and biofuels. It was concluded that, if all wasted organic matter and all residues was used as feedstock in biogas production, the biogas produced would be able to replace one fourth of the consumption of fossil fuels, which was 25 000 TWh in year 2006, in terms of energy.

The expansion potential for global agriculture is limited by availability of land, water and energy input. A future decrease in supply of fossil energy and ongoing land degradation in combination with a growing world population further enforces that the energy potential lies in using inedible organic waste and residues.
 
Available from:
Global Energy Systems