Energy consumption and greenhouse gas emissions of biodiesel production from rapeseed in Iran

The issue of searching alternatives for diesel fuel in transport sector that is one of the largest diesel fuel consuming sectors in each country has become more attractive nowadays. In this study, the energy consumption and CO₂ emissions of biodiesel production from rapeseed as an alternative for diesel fuel in transport sector was assessed in terms of three main stages including agricultural crop production, transport, and industrial conversion. The results revealed that the total fossil energy input cost was calculated as 28 122.16 MJ ha⁻¹ and the renewable energy output content (biodiesel as the final outcome) was estimated as 31 802.06 MJ ha⁻¹. The net energy returns and the fossil energy ratio were calculated as 3679.9 MJ ha⁻¹ and 1.13, respectively. It shows rapeseed could be a suitable energy crop for biodiesel production. CO₂ emissions assessment showed that the total greenhouse gas emissions over biodiesel production life cycle were 1054.98 kg CO₂ eq ha⁻¹ and the agricultural crop production stage ranks the first. In order to establish energy crops cultivation such as rapeseed and achieve the sustainable development, meteorological and water source availability data collected and analyzed for all the 31 provinces in Iran to generate a map of regions capable of rapeseed cultivation. The results revealed that 24 provinces among 31 provinces have a great potential for rapeseed cultivation.