From 2020, International Maritime Organisation (IMO) rules have banned ships from using fuels with a sulphur content above 0.5 percent, compared with 3.5 percent before, unless they are equipped to clean up sulphur emissions. This will be enforced by fines levied by the IMO’s member states. One of the attempts being made by the shipping industry to reduce its environmental impact is to use Fuel Cell Technology to deliver power to the vessels. Fuel cells as clean power sources are very attractive for the maritime sector, which is committed to sustainability and reducing greenhouse gas and also atmospheric pollutant emissions from ships. Fuel cells operating on hydrogen fuel are an efficient, environmentally-friendly, zero emission, direct current (DC) power source already applied to heavy duty bus, truck, and train applications, and are now under development for marine applications. The only emissions from a fuel cell are water vapour and some heat [1].Renewable hydrogen, generated from solar, wind, hydroelectric, and geothermal sources is considered an ideal fuel for decarbonising society. It can be used for industrial purposes, power generation, heating, and as a transportation fuel. This paper aims to show how the Hydrogen fuel cell systems are one of the best options for ships to meet the future and present IMO environment requirements, along with the challenges and conveniences of using renewable hydrogen compared to traditional marine fuels including a feasibility study of a Hydrogen fuel cell powered ferry. Keywords: IMO (International Maritime Organisation), sulphur emission, Fuel cells, sustainability, Greenhouse Gas, Hydrogen.