Rapeseed plantation biodiesel production systems require the transportation of goods, like raw materials, machines and tools, and products between various conversion stages of agricultural as well as industrial subsystems. Each transportation step requires the consumption of some energy. This consumption decreases the net amount of energy delivered out of the biofuel production system, and consequently decreases the energetic efficiency of the system. The majority of studies on biofuel sustainability are done by means of the LCA method with the use of a data average for some region and period of time. Such analyses do not reveal the possible causes of the conclusions determined. The present work deals with computer modelling of the influence of the energy consumed on those transport routes on the energetic efficiency of the production system. The model enables determination of the effects caused by changes introduced to technological parameters. The effects caused by variation of fuel consumption, the load capacity of transportation means, size of plantation, distribution and sizes of individual fields, distances between fields, plantation yield, and finally the distance between the plantation and the industrial facility are studied using the numerical model developed earlier. This approach is aimed towards identifying the reasons for the behavior of a system controlled by many somewhat coupled variables.
Synergies between industry and nature – An emergy evaluation of a biodiesel production system integrated with ecological systems