Renewable energy systems implementation in road transport: prospects and impediments

The transport sector accounts for about one quarter of the global carbon dioxide emissions. It is dominated by fossil fuels, leading to different negative impacts on humans and the environment. Over the last years, interest in alternative automotive powertrains such as different types of electric vehicles as well as low-carbon fuels has been increasing. The main objective of this paper is to provide review of the current state of the major renewable energy systems in road transport focusing on the EU. Based on a detailed literature review, the major prospects and impediments for the future use of biofuels, renewable electricity and green hydrogen in road transport are discussed considering policies implemented, as well as emission reduction targets set for the future with a special focus on passenger car transport. The major conclusions are: (i) The prospects of biofuels depend on their future economic and environmental performance as well as on land availability and the food versus tank discussion. (ii) The high investment costs of battery- and fuel cell electric vehicles are still a major barrier for their faster market penetration but they could be reduced in future due to technological learning. In addition, their contribution to the reduction of global greenhouse gas emissions is achievable only in combination with the increasing use of renewable energy sources in electricity generation