Method for determining at least one region of a road network reachable by a vehicle being driven within said road network, carrying out the following steps: a) the position of said vehicle and the amount (Es) of energy stored in said vehicle are identified; b) a dynamic model of said vehicle, which relates the energy consumed by said vehicle to the speed and acceleration of said vehicle, and to the slope profile of the road, is constructed; c) a line graph of said road network around said identified position of said vehicle is constructed by implementing the following steps: i) a direct graph of said road network is constructed with nodes and arcs, said nodes of said direct graph corresponding to the intersections of said road network, and said arcs of said direct graph corresponding to the roads connecting said intersections; and ii) said line graph is constructed from said road network with nodes and arcs, said nodes of said line graph corresponding to the arcs of said direct graph and said arcs of said line graph corresponding to the adjacency of said arcs of said direct graph; d) the energy consumed by said vehicle for each arc of said line graph is determined by means of said dynamic model of the vehicle and of an average speed of said vehicle on said arc in question, of the slope profile on said arc in question and of an acceleration of said vehicle to reach said average speed on said arc in question; and e) at least one region of said road network reachable by said vehicle with said amount (Es) of energy stored in said vehicle is determined by means of a shortest-path algorithm that minimizes, on said line graph, said energy consumed, said shortest-path algorithm being constrained by said amount (Es) of energy stored in said vehicle. a) the position of said vehicle and the amount (Es) of energy stored in said vehicle are identified; b) a dynamic model of said vehicle, which relates the energy consumed by said vehicle to the speed and acceleration of said vehicle, and to the slope profile of the road, is constructed; c) a line graph of said road network around said identified position of said vehicle is constructed by implementing the following steps: i) a direct graph of said road network is constructed with nodes and arcs, said nodes of said direct graph corresponding to the intersections of said road network, and said arcs of said direct graph corresponding to the roads connecting said intersections; and ii) said line graph is constructed from said road network with nodes and arcs, said nodes of said line graph corresponding to the arcs of said direct graph and said arcs of said line graph corresponding to the adjacency of said arcs of said direct graph; i) a direct graph of said road network is constructed with nodes and arcs, said nodes of said direct graph corresponding to the intersections of said road network, and said arcs of said direct graph corresponding to the roads connecting said intersections; and ii) said line graph is constructed from said road network with nodes and arcs, said nodes of said line graph corresponding to the arcs of said direct graph and said arcs of said line graph corresponding to the adjacency of said arcs of said direct graph; d) the energy consumed by said vehicle for each arc of said line graph is determined by means of said dynamic model of the vehicle and of an average speed of said vehicle on said arc in question, of the slope profile on said arc in question and of an acceleration of said vehicle to reach said average speed on said arc in question; and e) at least one region of said road network reachable by said vehicle with said amount (Es) of energy stored in said vehicle is determined by means of a shortest-path algorithm that minimizes, on said line graph, said energy consumed, said shortest-path algorithm being constrained by said amount (Es) of energy stored in said vehicle.