Electrolysers and fuel cells play a pivotal role in the production and utilization of hydrogen, with a focus on transitioning towards green hydrogen production using renewable energy sources. Currently, more than 95% of hydrogen is derived from fossil fuels like coal and natural gas due to cost considerations. However, with the shift towards green hydrogen facilitated by government policies and incentives, there are significant business opportunities emerging. Electrolysers function by splitting water into hydrogen and oxygen through electrolysis, with the key distinction being the utilization of renewable or nuclear energy sources for 'green' hydrogen production. Fuel cells then use the generated hydrogen to produce electricity, heat, and water, particularly in sectors like power generation, steel manufacturing, and transportation. The importance of electrolysers and fuel cells in climate mitigation is underscored by their ability to reduce carbon emissions in various industries. For instance, blending green hydrogen with natural gas in power plants can lower carbon intensity, while hydrogen is increasingly being used in steel production and transportation to promote low-carbon processes. The evolution of electrolysers has seen the development of alkaline and PEM technologies, with PEM electrolysis offering advantages like adaptability to rapid power level changes, making it well-suited for renewable energy integration. This progress highlights the pivotal role of these technologies in advancing the adoption of green hydrogen globally, essential for achieving decarbonization objectives and sustainable energy transition.