A comprehensive review on renewable power-to-green hydrogen-to-power systems: Green hydrogen production, transportation, storage, re-electrification and safety

Green hydrogen, produced from renewable energy sources, facilitates zero-emission electricity generation and supports self-peaking and cross-regional renewable energy dispatch, thereby promoting a virtuous cycle for SDG7 attainment. Despite its potential, there has been limited discussion on how green hydrogen can provide affordable, reliable, and sustainable energy for the world's poorest, particularly from the stakeholder perspective. This work provides a holistic review on renewable power-to-green hydrogen-to-power (RP2GH2P) systems, encompassing green hydrogen production, storage, transport, re-electrification, and safety, assessing technological characteristics and implementation challenges, with emphasis on stakeholders' concerns. Key challenges to developing the potential of RP2GH2P include: current efficiencies and costs are unappealing to governments and investors; the absence of comprehensive and effective tools for accurately assessing security risks perpetuates public concern; and the mechanisms and business models for RP2GH2P to provide grid peaking and frequency regulation are still undeveloped. Finally, conclusions show that continuous efforts on technological advancement and political support are required to enable a rapid development of RP2GH2P.