This thesis aims to determine whether a battery pack, hydrogen or methanol is the most suitable climate-neutral energy carrier for the next generation of Rijkswaterstaat patrol vessels. The highest plausible required energy storage capacity in three distinct operating region types was estimated. Through iteration of the ship resistance and the power plant weight, the technical feasibility of each carrier was tested in all three region types. It was found that the implementation of alternative energy carriers will require an increase in vessel size and weight if the current operational autonomy is to be maintained. For relatively small operating regions with strict speed limitations, batteries are the most suited carrier, while methanol is best suited for large patrol regions where patrol vessels operate at higher speeds.