This paper focuses on railway speed profiles and energy efficiency. It examines the train motion equations and proposes a novel procedure to determine a feasible eco-driving technique. The approach proposes to optimize the energy consumption in a railway route by maximizing the coasting phases. The method is applied by a series of successive steps. It finds the sections where coasting driving is applicable and classifies them in terms of energy efficiency, verifying if the coasting is applicable in the respect of the assigned regulation margin time. The procedure is tested on a real railway route. The aim of the paper is double: i) to focus on the feasibility of the proposal in terms of reduction of energy consumption; ii) to give evidence to numerical results obtained for a real railway route.