Integrating Solar Heat for Industrial Processes (SHIP) into the Circular Economy: A Pathway to Sustainable Industry

This study explores the technical, economic, and environmental feasibility of integrating Solar Heat for Industrial Processes (SHIP) into a circular-economy designed factory for acorn flour and granulate. Using the Greenius simulation tool, the performance of a field of 200 m $$^{2}$$ flat-plate solar collectors was evaluated across eight Mediterranean and North African sites: Portugal, Spain, Italy, Croatia, Turkey, Morocco, Tunisia, and Algeria. Three configurations were analysed: a solar-only system, integration of solar energy into an existing industrial plant, and the design of a new plant incorporating solar energy with storage and an auxiliary boiler. The simulations showed that thermal energy requirements reached 1498 MJ/t, with a peak demand of 8.96 kW. Annual solar thermal output ranged from 118.1 MWh to 187.1 MWh, with solar fractions of 48.9% to 84.5%. The LCOH varied by configuration, with the solar-only option reaching as low as 0.076€/kWh, while complete systems ranged from 0.089 €/kWh to 0.145 €/kWh. CO2 emission reductions reached up to 49.4 t per year depending on system setup and location. The results show that, in solar-rich regions, SHIP can reduce fossil fuel dependency and enhance energy stability. North African locations such as Larache and Tunis were the most suitable, offering higher solar shares and lower LCOH values due to favourable irradiance conditions. However, economic viability is influenced by local factors, including gas subsidies, infrastructure development, and the cost of thermal storage. These regional variables add trade-offs that must be accounted for in feasibility assessments. Integrating SHIP into agri-food sectors, such as acorn-flour processing, offers a scalable, low-emission solution that aligns with broader sustainability and circular-economy goals.