Energy supply security for the Aegean islands: A routing model with risk and environmental considerations

Energy security is important for islands not connected to mainland electricity grids. The Aegean archipelago comprises scattered islands, whose electricity supply relies on oil-based thermal power plants. These islands attract large numbers of tourists, while the archipelago is an environmentally sensitive area. Efficient maritime transportation of crude oil is critical for maintaining adequate power supply in the Aegean islands, especially during tourist seasons. Tanker closed-sea shipping operations in the Aegean Sea raise considerations on carbon footprint impacts. Also, despite potential impacts to local economies and the environment, the case of a maritime accident leading to an oil spill is largely overlooked. We investigate the possible integration of environmental and accident related objectives, in the decision-making process of planning an efficient oil maritime transportation service for the Aegean archipelago. We showcase a risk mitigation strategy for oil transport route planning considering spill-related impacts to local, tourism dependent economies under a more socially and environmentally conscious policy framework. We model the problem as a multi-objective capacitated vehicle routing problem and solve it using an alternating objective genetic algorithm. Results show that certain routes are considered optimal for both objectives, while risk reduction may be achieved at small operational cost increase.