As often as it is now being used, the hydrogen economy term is rarely defined.  As a result, the concept is rather vague. Currently, it essentially simply refers to the concept of using H2 as a source of low- or zero-carbon energy for meeting the clean power needs of a location such as a city, province, state, region, country, or even the world. As governments around the world increasingly implement strategies to combat climate change, this explains why the focus on a hydrogen economy – and the use of the term – have started making their way into the spotlight and news headlines fare more frequently. Many governments worldwide believe that H2 will play a core role in their efforts to decarbonize and meet their climate targets. Uses for H2 include everything from electricity generation, backup power, auxiliary power, heat, or combined power and heat, among others. It can be used to power everything from passenger vehicles to aircraft and shipping vessels, as well as industrial machinery in some of the most polluting industries in the world, such as chemical and steel making.

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