Nowadays, maritime transport sustains worldwide trade and fosters economic development. Global maritime trade continues to grow annually and the number of seaborne passengers increases commensurately, as giant cruise ships become ever more popular. This continued growth poses a number of challenges which the shipping industry must address in order to continue competing with other forms of transport. New technologies are being investigated or used to help shipping meet these challenges. Most of them are dependent on electricity which is a green and particularly versatile form of energy.