An Overview of the Green Hydrogen Value Chain Technologies and Their Challenges for a Net-Zero Future

As hydrogen emerges as a pivotal energy carrier in the global transition towards net-zero emissions, addressing its technological and regulatory challenges is essential for large-scale deployment. The widespread adoption of hydrogen technologies requires extensive research, technical advancements, validation, testing, and certification to en-sure their efficiency, reliability, and safety across various applications, including indus-trial processes, power generation, and transportation. This study provides an overview of key enabling technologies for green hydrogen production and distribution, high-lighting the critical challenges that must be overcome to facilitate their widespread adoption. It examines key hydrogen use cases across multiple sectors, analysing their associated technical and infrastructural challenges. Technological advancements re-quired to improve hydrogen production, storage, transportation, and end-use applica-tions are discussed. The development of state-of-the-art testing and validation facilities is also assessed, as these are vital for ensuring safety, performance, and regulatory compliance. This work also reviews ongoing academic and industrial initiatives in the UK, aimed at promoting technological innovation, advancing hydrogen expertise, and developing world-class testing infrastructures. This study emphasises the need for stronger, more integrated collaboration between universities, industries, and certifying bodies. Building a strong network that promotes knowledge sharing, standardisation, and innovation for expanding hydrogen solutions and creating a sustainable hydrogen economy.