THE MAIN OBJECTIVE OF THIS R&D IS TO DESIGN, MANUFACTURE AND HYDRO TEST A LOW-COST AND HIGH-PERFORMANCE, PARTICLE–TO–SCO2 DOUBLE HELIX HEAT EXCHANGER (HX) FOR CONCENTRATED SOLAR POWER (CSP) USING HIGH-SPEED ADDITIVE MANUFACTURING (AM) AND A COST-EFFECTIVE YET HIGH-PERFORMANCE ALLOY, AIMING AT HELPING REDUCE THE OVERALL COST OF LEVELIZED COST OF ELECTRICITY (LCOE) OF CSP.