External costs of the Dieselgate - Peccadillo or substantial consequences?

摘要

The Dieselgate has changed the public view of diesel powertrains and local authorities have issued first driving bans on diesel cars in Germany. Nevertheless, a systematic calculation of the external costs of the Dieselgate considering different car models and a variety of emissions has not yet been conducted. We compare the results, which reflect emissions under test bench conditions, with those of diesel cars under the assumption that NOX emissions reflect realistic driving behavior. We find that diesel cars with idealized emissions are superior to petrol cars with regard to external costs and that electric cars have only partially lower external costs than diesel cars. However, when realistic driving behaviors are considered, diesel engines constitute the worst powertrain in all cases. Our results show that the Dieselgate has led to substantially higher external costs than cars which would comply with environmental regulations under realistic driving conditions.