This paper presents a comparative analysis of electric, hydrogen and biofuel transitional pathways to a future sustainable road transport in Iceland, a country with a renewable-based energy system. The analysis is based on a system-dynamics model of Icelandic energy and transport systems (UniSyD_IS). The model is divided into four main modules: fuel supply, fuel prices, refueling stations, and fuel demand. It simulates the long-term evolutions of light and heavy-duty vehicles, taking into account the supply and utilization stages of alternative fuels. Three scenarios are defined to promote the fuel supply infrastructure for three cases of hydrogen, biofuel and electric vehicles. The simulation results for these scenarios are compared in terms of different energy, economic, and environmental indicators. The findings indicate that the electricity pathway has advantages over others in reduction of total fuel demand, mitigation cost, and profitability of fuel supply. The biofuel pathway would be the most attractive alternative in terms of emissions reduction, share of alternative fuels, and consumer economic benefits. The analysis shows that the hydrogen scenario could be advantageous in reducing fuel import and consumer fuel costs, although it has the highest cost of vehicle ownership and infrastructure development. (C) 2015 Elsevier Ltd. All rights reserved.