Trolleybuses and the European cityscape : energy choices under environmental pressure (London, Paris, and Rome, 1930s)

International audienceTrolleybuses and the European cityscape : energy choices under environmental pressure (London, Paris, and Rome, 1930s) Arnaud Passalacqua (Paris Diderot University) During the interwar period, the European cities faced new mobility problems. The substitution of horse power by different kinds of motors, which began before the First World War, was only completed during the 1930s. Beside the intensification of car traffic, one of the most striking changes of that time is the dismantling of tram networks, which occurred in a few cities. At least London, Paris and Rome have chosen to totally or partially dismantle their tram networks and to develop different enhancements of mobility. A new system, the trolleybus, could easily find a place on the dismantled tram lines, for energy and cityscape reasons. This was the case in London, whereas Paris only used motor buses in place of trams. Rome followed an intermediate way by developing a mix of mobility, based on trams, trolleybuses and motor buses. Our paper will address the different elements behind the decisions made in the three cities on the question of trolleybus. The hybrid nature of this system, powered by electricity supplied by overhead wires but rolling on pneumatic tires, leads to special links between energy and cityscape. We will try to understand the role of these environmental factors in the debates of the 1930s. Our hypothesis is that these environmental considerations have been partially exploited in order to hide other kinds of reasons behind the choices made in the different contexts, such as industrial interests, social fears or political choices. And this game explains the adoption or the rejection of trolleybuses. As a result, despite transfers and rivalry between cities, the 1930s built original mobility supply in these three European capital cities