Abstract
Current global climate mitigation efforts are considered insufficient to meet international carbon emission targets. Modeled scenarios showing how these targets can be reached are underpinned by further renewable energy development. Offshore renewable energy has been shown to have energy potentials that are more than double the global electricity demand. Previous assessments investigating Offshore renewable energy potentials typically focused on a single resource type and use a wide range of units. However, these assessments have not been compared on a global scale and therefore it is largely unknown which resource types have the largest energy potentials at any given location. This study undertakes a global cross-resource assessment of marine renewable energy potentials, collecting previous marine renewable energy resource assessments in a single database with standardized energy potentials. The assessments collected are compared to the theoretical energy potential of other resource types at each location. Tidal and ocean currents and offshore solar are found to have consistently higher energy potentials than the other resource types. An expanded feasible global energy potential for tidal currents and offshore solar is found. Results show if only 2 % of this potential is harnessed from future turbine development, CO2 emissions could be significantly reduced helping meet international emission targets and United Nations Sustainable Development Goals.