Hydrogen is a clean gas that produces only water as an emission when used as fuel for cars, heavy transport, power generation and industry. Hydrogen is versatile and can be used in a broad range of applications. Hydrogen can be used, like natural gas, to heat homes and industry, and for cooking. Hydrogen can power fuel cell electric cars, trucks, buses and trains. It can also be used to generate electricity (through fuel cells). Finally, hydrogen can be exported, either as an energy carrier or for use as a chemical feedstock – hydrogen‘s most common use today is as a chemical ingredient. Combined across these use cases, hydrogen could account for almost one-fifth of total final energy consumed by 2050. This would reduce annual CO2 emissions by roughly 6 giga tonnes compared to today’s technologies.