double energy = 0;
Map<Double, Gear> map; /*= new HashMap<>();*/

for (Section sec : listSections) {
  for (Segment seg : sec.listSegment()) {
    map = calculateInstanceEnergy(vehicle, seg, currentSpeed, time, true, false);
    for (Map.Entry<Double, Gear> entry : map.entrySet()) {
      energy += entry.getKey();
    }
  }
}