Figure 2: Global Energy Production from Petroleum and Food Products. The conversion of crop biomass to energy dense oils or fuels results in a loss of ≥ 50% of embodied energy. Food crops cannot therefore replace a globally significant proportion of energy as oil, without dramatically increasing pressure upon food security. The data presented for oil is sourced from BP Statistical Review of World Energy 2012 [1] and for food data is sourced from FAOSTAT [8], with general food calorific values calculated as previously by Stephens et al. [43].