The recent discussions about emissions in a number of cities in Austria, Europe and Asia have also brought up the question of the performance of gondolas in this field. A study conducted at the Vienna University for Economics has calculated the emissions of several mass transportation system. Gondolas have shown to have the lowest number of emissions behind metro or tram systems and commuter trains. Very badly perform busses in comparison. Gondolas are environmental friendly in a number of aspects, with low emissions being one of the strengths of the system.