This thesis aims to investigate the environmental impacts associated with the entire life cycle of key components within a Hydrogen Valley, where multiple end-users are fed by green hydrogen. To comprehensively understand the hydrogen valley concept, eight comparative case studies were conducted to investigate different technological pathways, including hydrogen production through electrolysis and steam methane reforming, transportation via pipeline and tube trailers, storage options, and end-use applications such as fuel cell electric vehicles, heavy-duty trucks, steelmaking, and ammonia production. The results reveal that producing hydrogen through electrolysis powered by renewable electricity can reduce greenhouse gas emissions by more than 70% compared to conventional, fossil-based pathways.