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Sammanfattning: By initiative from Sweco Rail, we have made a comparison between fixed and automatic tensioning devices for tramways to determine when there is an advantage to choosing an automatic device instead of a fixed solution. Main focus has been tramways in city environment, with extra focus on Gothenburg. The report attempts to answer the following questions: • When should the choice be an automatic tensioning device, and when should it be fixed? • What types of issues may be encountered when changing a fixed system into a system with automatic tensioning? • Will an automatic tensioning device improve the possibilities for maintenance and dependability compared to a fixed solution? To be able to draw conclusions from our results, a null hypothesis (H0) has been formulated: H0: There is no difference between an automatic tensioning device and a fixed tensioning with respect to: • Maintenance • Installation costs • Dependability The report is produced with a combination of literature studies, interviews and an international outlook towards other tramway systems using Google Maps Street View. Results show that there are savings to be had transitioning a fixed system into an automatically tensioned, although the profit will be small due to the fact that only about a hundred man hours are spent each year tensioning the system by hand. We can also see that it is important to ensure that all other necessary changes to the system are made before exchanging the tensioning solution. Otherwise there will be little effect. Most problems arise when there are two or more tramway lines crossing each other. We find no clear general solution to how to solve the tensioning issue in these situations, but we note that most newly built modern tramways solve the problem by removing the catenary completely from crossings and utilizing battery power instead.