The maritime transport industry significantly contributes to global greenhouse gas emissions, creating an urgent need for a transition to sustainable practices within the sector. This paper explores various forms of renewable energy that can be applied in shipping, including solar energy, wind energy, hydrogen energy, biomass energy, as well as water and geothermal energy. The advantages and challenges of each of these sources are analyzed, along with their ability to support the sustainability goals of the maritime industry. Examples of innovative vessels utilizing renewable energy, such as MS Tûranor PlanetSolar, the first solar-powered ship to circumnavigate the globe, and MV Canopée, a hybrid cargo ship integrating wind energy, are also presented. These examples illustrate the practical applications of renewable energy sources and their potential to reduce emissions in shipping. In light of international regulations, such as FuelEU Maritime, the paper emphasizes the necessity for collaboration between the industry and regulatory bodies to ensure the successful transition to low-carbon technologies.