Reduction of emissions at Scania Engine Assembly

Abstract: This master thesis is carried out in collaboration with the company Scania which is a provider of transport solutions. The thesis is carried out at Scania’s production unit Engine Assembly where engines are assembled, tested and painted. All engines proceed through a standard test procedure while some of the engines also proceed through special test procedures carried out in the ”Audit Area”. The special test procedures are the focus of this report. The special test procedures are called Conformity of Production-tests (COP) and Quality Assurance-tests (QA). COP-tests are needed to show that the products are in conformance with relevant administrative provisions and technical requirements that are regulated by law. QA-tests are needed in order for Scania to know that their products have the right quality and characteristics. These tests are currently carried out with mainly fossil diesel. The possibility to use alternative fuel during the tests and thus reduce the emissions from the Audit Area is analyzed in the report. The thesis project is divided into four parts. The first part includes investigation regarding what alternative fuel that is technically possible to use. This is done by gaining information regarding engines and fuels and by performing three experiments on one engine type. The second part includes deriving the yearly emission reductions of tailpipe CO2 and life cycle CO2e related to changing the fuel-use. This is done by estimating the fuel consumption of the relevant tests over one year as well as finding the emission factors for the fuels that are currently used as well as for the alternative fuel. The third part includes evaluating the availability of the alternative fuel by performing a literature study. The last part includes finding the physical modifications needed to change the fuel-use, this is done by observations and communication with relevant Scania employee. It is concluded that the fuel that is technically possible to use in as many engine as possible is the renewable diesel Hydrotreated Vegetable Oil, HVO. However, the COP- and QA-tests consist of different parts and not all of the parts are legally or technically possible to run with HVO. The experiments give varying results and show that it is important to further evaluate the technical possibility of running parts of the tests with HVO. The results show that the yearly fossil tailpipe CO2 -emission reductions could be almost 75 % when changing the fuel-use. The LCA CO2e-emissions could be reduced by 47-64 % when changing the fuel-use. However, these emission reductions are based on a best-case scenario which might be somewhat optimistic considering the number of parts of the test that can be run with HVO. For that scenario to be possible it might require changes to test-layouts, further experimenting and further studies. Regarding the availability of HVO the literature study shows that the future availability of HVO is somewhat unclear and needs to be further looked into if this change in fuel-use is implemented. Lastly, the modi cations needed for changing the fuel-use are mainly related to fuel storage and fuel supply-system.