As the U.S. marine industry pushes toward decarbonization, our domestic fleet will be the first to adopt and experiment with different propulsion methods. For the majority of passenger vessel operations, the most viable and fully developed option for substantively reducing carbon emissions will be all-electric propulsion—where it can be practically implemented. However, certain vessels may not be able to accommodate marine battery systems due to weight or space constraints. For others that operate on longer routes, have highly variable operating profiles or serve rural areas where the addition of shoreside charging infrastructure is impractical, all-electric propulsion may not be achievable.…