Marine propulsion systems and control methods

A propulsion system for a marine vessel, the propulsion system comprising:

• a marine drive configured to propel the marine vessel;
• a control system operatively coupled to the marine drive and configured to control operation thereof, wherein the control system is configured to:
• receive a destination for the marine vessel;
• receive a demand request for operating the marine drive and to operate the marine drive at an actual demand corresponding to the demand request;
• determine a required energy for the marine drive to propel the marine vessel to the destination at the actual demand;
• determine a remaining energy of an energy source available for operating the marine drive;
• and
• compare the required energy to the remaining energy and, when the remaining energy is less than the required energy, automatically iteratively reduce the actual demand of the marine drive until the remaining energy equals or exceeds the required energy determined for the marine vessel to reach the destination.