Fuel Switching Strategies for Decarbonising the Glass Industry Using Renewable Energy and Hydrogen-Based Solutions

This study addresses the decarbonisation of the glass industry from an integrated energy system perspective, analysing the role of renewable electricity, furnace electrification, and hydrogen in meeting the high and continuous thermal demands of glass melting. While direct electrification represents the most energy-efficient option, its implementation is challenged by the intermittent nature and limited operating hours of renewable generation, scale constraints, and technological limitations in replacing fossil-based processes, highlighting a potential complementary role for hydrogen. A general methodological framework is first developed and then applied to a representative oxyfuel glass furnace using mixed-integer linear programming (MILP) optimisation that minimises melting costs while accounting for variable solar and wind generation, battery storage, and hydrogen production and storage. The results show that high levels of furnace electrification combined with wind-dominated renewable supply yield the lowest decarbonisation costs, which can become negative at moderate decarbonisation levels. Under the current solar–wind capacity expansion mix, the integration of battery and hydrogen storage extends achievable emission reductions from around 50% to 80%, with hydrogen acting as a complementary solution to electrification. Sensitivity analysis of energy and carbon prices, as well as technology investment costs, identifies the economic conditions in which storage-based solutions become cost-effective, highlighting the strategic role of hydrogen under conditions of low electricity prices and high fuel prices. The findings demonstrate viable pathways for deep decarbonisation of the glass sector and provide a transferable methodological framework for optimal renewable energy integration in other hard-to-abate industrial sectors facing similar constraints.