Renewable hydrogen, often synonymous with green hydrogen, is hydrogen produced exclusively using electricity from renewable energy sources through water electrolysis. This ensures its production cycle is carbon-free, distinguishing it from hydrogen derived from fossil fuels (gray hydrogen) or fossil fuels with carbon capture (blue hydrogen). Renewable hydrogen leverages the abundance of renewable resources like solar, wind, and hydro, converting their intermittent power into a storable, transportable energy carrier. It plays a dual role: as a clean fuel for transportation, industry, and power generation, and as a means to store excess renewable energy, smoothing out supply fluctuations. Technologies enabling its production include advanced electrolyzers (PEM, AEM) that efficiently utilize variable renewable electricity, while storage solutions like metal hydrides and high-pressure tanks ensure its practical deployment. As a linchpin of the energy transition, renewable hydrogen supports global efforts to reduce carbon emissions and achieve energy independence.