As part of the decarbonisation efforts in high-temperature industries, hydrogen is emerging as a key alternative fuel to reduce overall CO₂ emissions. In Europe, natural gas—composed of more than 90% methane—is currently the predominant fuel for glass industrial furnaces. Integrating hydrogen into this context requires the development of an industrial microgrid for on-site hydrogen production and storage. In this system, electricity is supplied by both the power grid and Renewable Energy Sources (RESs), serving the demands of a PEM electrolyser (ELY) and the electrical load of the furnace. The remaining thermal demand of the furnace is met by a combination of natural gas and hydrogen. The optimisation presented in this study foresees the Energy Management System (EMS) approach: for this industrial microgrid layout, the minimisation of operational costs of all the components is performed on an hourly time step, based on glass production, RES generation forecasts and gas and electricity price projections for the following 24 hours. The effectiveness of the system is proven by means of the microgrid simulation over a time period of 20 days, using real data from the industry. The optimisation model accounts for low-emission targets and furnace load constraints. The purpose of this paper is to investigate the flexibility and feasibility of hydrogen integration in a glass industrial setting.