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Natural fluctuations in renewable energy sources demand for effective large-scale energy storage solutions to manage the possible time mismatch between energy production and consumption. Among the most popular high-temperature thermal energy storage (TES) systems, molten salts filled tanks proved as one of the most attractive and environmentally friendly solutions due to their high boiling points, low viscosity, low vapor pressure and high volumetric heat capacities, along with their low cost and market readiness. Concentrated Solar Power (CSP) plants are among the main applications benefiting of the molten salts as heat transfer fluids (HTF) to store thermal energy providing a potentially constant on-demand supply of solar power without the need for fossil fuel backup systems. However, the low thermal conductivity of conventional solar salts limits the resulting energy storage density and leads to large stored volumes, translating in a relatively high cost. Differently, metallic Phase-Change Materials (mPCM) can provide higher thermal conductivities and energy storage densities due to the much higher operating temperature range (up to 1400°C), which enable to achieve performances comparable with other benchmark storage technologies. Nevertheless, the demanding operating conditions of these materials require the use of compatible refractory materials for the production of their containers. Chemical Vapor Infiltrated (CVI) SiC/SiC composites, where the silicon carbide (SiC) based matrix is deposited from gaseous reactants on to a heated substrate of SiC fiber preforms, excel for their high temperature and corrosion properties along with a high fracture toughness and low density, making them ideal candidates for the replacement of metals and ceramics for applications in aggressive environments. However, the long manufacturing times (of the order of several weeks) and the run-to-run reproducibility severely limit the broad usage of this technology. In this framework, Microwave-assisted CVI (MW-CVI) shows several advantages in the infiltration of SiC/SiC composites, mainly thanks to its ability to induce an inside-out densification pattern, thus reducing the processing times of about one order of magnitude. The relevance of SiC/SiC composites can be still more strengthened developing easier and more rapid techniques for the joining among CMCs, which would open the use of these materials to several strategic applications. The MicrowavE-assisted manufacturinG of cerAmic composites for improved thermal energy STORAGE systems (MEGASTORAGE) project will address these challenges by proposing innovative MW-assisted heating technologies to abate production costs and develop joining technologies to enable the utilization of SiC/SiC components within CSP applications and beyond. MEGASTORAGE RTD activities involve some of the principal Italian experts and research institutes in the field and results strategic from the industrial and economic point of view as a part of the challenges addressed within the M2C2 section of the PNRR.