Transition towards carbon-neutral districts based on storage techniques and spatiotemporal energy sharing with electrification and hydrogenation

Electrification and hydrogenation in buildings and transportations are estimated to reduce around 30% carbon emission in 2060, whereas the current literature provides few state-of-the-art reviews on advanced materials and approaches on electrochemical battery and hydrogen (H 2 ) for the transition towards carbon-neutral districts. In this study, a systematic and comprehensive review on the transition towards carbon-neutral districts was conducted with energy storage techniques, spatiotemporal energy sharing, electrification and hydrogenation. Cutting-edge technologies on electrochemical battery and hydrogen storage are reported, in terms of advanced materials, prioritized storage approaches, and bottleneck technical challenges. Principal roles and underlying mechanisms on electrochemical battery and hydrogen storages were demonstrated, together with application prospects, such as decentralised and centralized battery sharing strategies, and the transfer from building-integrated micro-H 2 systems to H 2 stations. Afterwards, feasibility and possibility of mobility integration in a district energy community have been demonstrated, in terms of current status and public infrastructures (like electric vehicle and hydrogen refueling station), opportunities for electrification and hydrogenation in transportations, economic analysis on interactive energy sharing frameworks, and synergistic function with mutual benefits. In order to improve the efficiency of H 2 systems with idling constraints, social acceptance among building owners on high-pressure H 2 storage, and to provide frontier guidelines on mobility integration in within-city and inter-city energy systems, novel energy frameworks have been proposed, for district energy sharing and inter-city energy migration. Research results can provide optimal planning on national energy strategies, flexible integration, technical guidelines and economic incentives, to make preparations for the carbon neutrality transition.