Wind to Diesel : A conceptual design study of farm-based electrodiesel production

Sammanfattning

The objective of this master thesis was to design a small-scale conceptual production facility for electrodiesel placed on a farm. Powering the facility with wind power was also investigated. Furthermore the solution was compared to a case farm to explore the suitability for electrodiesel production in an agricultural environment. This was assumed to be 100 ha, require 80 l/ha of diesel and located in Östergötland County. The execution of the thesis was done at Energifabriken, Linköping in collaboration with RISE aswell as Agtech Sweden who provided the original idea. The study concluded that the system should consist of a Polymer Electrode Membrane type electrolyzer, a Reverse Water Gas Shift reactor, Fischer-Tropsch Synthesis and finally a H2 storage. The estimated cost of the facility came out to 51.5 MSEK. The H2 storage was required to couple the production with the wind power production. More over regarding the power source, the wind power was deemed a suitable choice as it provides revenue from it is grid interaction. However, it is required to be over dimensioned to provide a continuous production of electrodiesel. Lastly the production facility was not a profitable investment and required external funding to be feasible for application on a farm. Electrofuels have the potential to lower the climate impact from combustion engines without requiring new engine technology. By producing diesel fuel from only CO2, water and electricity there is potential to reduce further emissions from combustion engines. This is especially relevant within agriculture as the rate of upgrading vehicles is very low. Research and projects within on the subject are many, showing the topicality of the area. However they are all conducted on large-scale facility, leaving a gap of small-scale solutions. The method used was inspired by the five-step method for concept generation, but adjusted to consist of four. The first step was to clarify the problem to identify necessary components. A case farm was also created as part of the clarification, to provide an agricultural frame of reference. Construction criteria for the facility was also established. The following step was to conduct a search to understand what components are available, interviewing manufacturers and researchers, and to identify possible solutions. More than 40 companies and researchers were contacted. From this a selection from the solutions found was made, using Kriterieviktsmetoden. To analyze the system a Python-model was created. As part of the model wind power production and interaction with the grid was simulated. This allowed for an iterative process to create a reference system, suitable for the case farm. A sensitivity analysis was then conducted on the system where the rated power and reliance of wind power production was varied.