Decarbonizing industrial heat through renewable and electrified solutions: Application to a jam waste valorization process

Industrial heat supply is a major contributor to global greenhouse gas emissions, making its decarbonization a key challenge for chemical industry. In this approach, renewable and electrified heat sources are potential alternatives to fossil-based steam generation. This work compares three approaches for supplying thermal energy to a jam waste valorization process designed with two alternative waste treatment routes, anaerobic digestion (AD) or gasification (GA): (i) steam generation using natural gas (Base Case), (ii) renewable steam generation (CSP and biomass), and (iii) direct electric heating (wind turbines, PV-panels, CSP and biomass), considering both economic and environmental performance. Competitiveness of renewable alternatives is assessed over a 15-year time horizon. The results show that CSP-based steam incurs the highest capital costs: 30-40 times higher than the Base Case for AD and 10-12 times for GA. In contrast, biomass-based steam is economically viable when low-cost feedstocks such as corn stover, switchgrass, or wood pellets are used, yielding costs comparable to or slightly below natural gas. Among these, corn stover results in the most competitive feedstock. All electrified scenarios exhibit substantially higher investment costs (500-1600 M€), preventing economic competitiveness. Environmentally, nearly all renewable alternatives achieved substantial GHG reductions: 57-74% for AD and 54-68% for GA with renewable steam, and 20-70% under electrification depending on the electricity source. AD systematically outperformed GA. Overall, renewable heating technologies provide significant environmental benefits, and with technological development, cost reductions, and resource availability, renewable heat could become both economically and environmentally sustainable, supporting industry progressive decarbonization.