What is green, blue and grey hydrogen?

As the oil and gas sector looks towards new fuels to power the future, hydrogen is often touted the ultimate future fuel. But there are many forms that hydrogen takes, especially in the context of clean energy. So how do we know what’s actually clean hydrogen? Hydrogen is the lightest and most abundant element in the universe. It can come in many forms and can be produced through many processes that are easy to incorporate at a traditional terminal: electrolysis, steam methane reformation and biomass gasification. Hydrogen is considered an attractive option for the switch to clean energy. Its combustion or use in fuel cells does not produce carbon emissions or air pollutants directly, and it can be produced cleanly via solar-powered electrolysis, for example. However, the environmental impact of hydrogen production largely depends on the method used. Green hydrogen, produced through electrolysis with renewable energy, is considered environmentally friendly, while grey hydrogen, produced from fossil fuels, has a higher carbon footprint. With the growing interest in hydrogen and how it can be produced sustainably, it is easy to misunderstand that hydrogen can take different...