Zero-energy hydrogen economy (ZEH₂E) for buildings and communities including personal mobility

Hydrogen economy has become topical due to the rapid development of hydrogen vehicles and national hydrogen roadmaps. The zero-energy concept has been developed to support energy policy making with an aim at designing and building sustainable buildings and communities. In this article we define the concept ‘zero-energy hydrogen economy’ (ZEH₂E) as such a zero-energy system, where hydrogen is one of the key energy carriers. We review recent research on the integration of zero-energy hydrogen economies at the level of single buildings and communities. We conclude that the energy use of transportation, hydrogen supply from other than renewable energy resources (e.g. as a by-product of industrial processes), and supporting metrics including the grid interactions, energy matching and reliability should be included in the zero-energy definition. We deduce that the research should focus on finding solutions that facilitate the parallel operation of conventional centralized systems and decentralized hydrogen economies. More research is needed to understand the impacts of the exchange of various energy types between vehicles, buildings and/or communities and hybrid smart grids. Innovative sharing economy models, incentives and energy policies are required. The awareness and acceptance of hydrogen technology among occupants and home owners should be surveyed and promoted.