I hold a firm belief in the indispensability of green hydrogen for the planet's future, serving as a crucial decarbonization vector. As an expert in hydrogen technologies at ESE Engineering Services for Energy, I am privileged to delve into the study and optimization of green hydrogen production and utilization systems.Being an integral part of the STREAM consortium, ESE stands ready to assist clients in harnessing a diverse array of renewable energy sources. These include photovoltaic, concentrated solar, onshore and offshore wind, as well as various biomass and organic fractions of municipal solid waste. Leveraging these energy sources, my role as a hydrogen expert involves sizing green hydrogen production facilities to optimize the Levelized Cost of Hydrogen (LCOH). Tailoring the system according to end-user requirements, we ensure characteristics such as purity, pressure, and availability are finely tuned.A significant aspect of my work at ESE involves guiding end-users in adapting existing systems to accommodate increasing percentages of hydrogen. This not only fosters sustainability but also aligns with our collective commitment to a greener, more resilient future.