Receiver Design and On-Sun Testing for G3P3-USA

This paper summarizes the evolution of the Gen 3 Particle Pilot Plant (G3P3) receiver design with the goal of reducing heat losses and increasing thermal efficiencies. New features that were investigated included aperture covers and shrouds, active airflow, multistage catch-and-release devices (stairs), and optimization of receiver cavity geometry. Simulations and ground-based testing showed that a reduced receiver volume and aperture shroud could reduce advective heat losses by ~40 – 50%, and stairs could increase opacity and reduce backwall temperatures. The reduced vo lume receiver and stairs were selected for on-sun testing, and receiver efficiencies up to 80 – 90% were achieved in the current test campaign. The receiver thermal efficiency generally increased as a function of incident power and particle mass flow rates. In addition, particle outlet temperatures were maintained to within ±10 °C of a prescribed setpoint temperature up to ~700 °C using a PID controller that adjusted the particle mass flow rate into the receiver in response to the measured particle outlet temperatures.