Gen3 Solid Particle Receivers (SPR) are being designed to generate high temperature heat transfer and storage media to drive high efficiency advanced turbine cycles in order to increase overall plant efficiencies and reduce the levelized cost of electricity (LCOE) of Concentrated Solar Power (CSP) plants. Supercritical CO2 (s-CO2) advanced turbine cycles have the potential to raise CSP plant efficiencies but require high fluid temperatures (>720oC) and therefore require the use of costly high nickel alloy tubing. Conceptual design efforts have displayed a number of advantages of fluidized-bed systems for s-CO2 SPR systems including the ability to handle high temperature solid particles, maintain reliable operation and offer the means to yield much higher heat transfer coefficients over packed / moving bed designs. Higher heat transfer coefficients reduce the overall footprint of the vessel, but also minimize the amount of costly high nickel alloy surface in the construction of the vessels which ultimately factors into the capital cost. While fluidized beds have a proven track record in industrial and utility applications including gas solid combustion systems for utility boiler applications, the higher temperature of operation of the proposed design and the novel use of a sCO2 power cycle, require innovative approaches in design to meet DOE cost reduction objectives and efficiency targets. The minimization of the surface area and weight of costly high nickel alloy materials required for the high temperature operating sections is one key focus areas. Additionally, the fluidized bed needs to be designed to greatly reduce heat loss and operating costs associated with the use of a fluidization air medium. The efficiency of the sCO2 cycle is sensitive to, and inherently tied to pressure drop. Therefore, a main parameter of interest is the need to operate at much lower pressure drops than traditional heat exchanger systems. Use of fluidization gas can lead to heat loss and parasitic energy consumption due to the use of fans and blowers. Traditional boiler designs that drive steam-rankine cycles generally do not require extensive use of high nickel alloys, and weight/pressure drop are not as big of a concern. Therefore, the systems tend to use heavy rugged components e.g. large diameter thick tubes in the construction of the boiler. The sCO2 cycles present unique challenges that warrant investigation of novel approaches. The proposed pulsed fluidized bed novel design will address the shortcomings of traditional fluidized beds while harnessing its inherent benefits. The phase I design and simulation efforts will focus on the product design incorporating novel layouts and operational characteristics, feasibility assessment and testing of the hydrodynamics and heat transfer properties and a commercialization potential assessment of the technology that demonstrates the promise of the technology to meet DOE cost objectives. Future phase II and III efforts would perform additional testing and develop a prototype that would be field tested in order to work towards commercial applications of the technology.
