Hybrid Concentrated Solar Thermal and Wind Resistive Heating Systems as Key for Competitive Low Emission Industrial Process Heat Generation

Abstract

Concentrated Solar Thermal (CST) has been addressed as a promising technology for industrial heat decarbonization; however, its use is still limited to low-medium temperature processes (50-250°C). The following analysis explores its feasibility at high temperature employing a parabolic trough solar field with a direct two-tank storage configuration using molten salts both as heat transfer fluid and storage medium, to provide a constant 10 MW_TH power to heat up a process fluid to 500°C. Through an economic optimization, various levels of process decarbonization are examined, also including CST hybridization with resistive electric heating powered by photovoltaic and wind energy generation and computing CO₂ emissions on a life cycle assessment (LCA) basis. The results indicate that CST is a viable alternative to direct electrification up to 30-50% process decarbonization, while hybrid systems show potential to reduce costs up to 40% at high decarbonization levels. Moreover, although achieving 100% process decarbonization remains still unfeasible, decarbonization levels up to 80-95% appear economically viable when considering up-to-date costs and the forecasted carbon tax.