Project Name: Gen3 Gas-Phase System Development and Demonstration
Funding Opportunity: Generation 3 Concentrating Solar Power Systems
SETO Subprogram: Concentrating Solar Power
Location: Hampton, NH
SETO Award Amount: $7,570,647
Awardee Cost Share:  $1,899,003
Principal Investigator: Shaun Sullivan

Download the Executive Summary for this project.

This project will develop a megawatt-scale concentrating solar-thermal power (CSP) system using a gaseous or supercritical heat-transfer fluid and low-cost solid particle thermal energy storage. An array of newly designed heliostats will be used to heat a novel receiver that can deliver thermal energy to a storage system using flowing solid particles. The particles will be capable of storing at least 9 megawatt-hours of energy at 750° Celsius. The stored energy can then be delivered on demand to a high-efficiency supercritical carbon dioxide power block, which converts thermal energy into electricity, creating low-cost, dispatchable power. This project is a Topic 1 award under this funding program, conceptualizing a fully integrated gas CSP thermal transport system. If selected for the third phase of this award, the system will be developed into a test facility.

Gen3 CSP energy storage system

Energy from the sun is reflected by the solar field (A) and absorbed by the solar receiver (B). The captured energy can be used to power a high-efficiency engine (C) or delivered to the thermal energy storage system (D). Image courtesy of Wagner/NREL.


To build a CSP system with optimal operability and performance, the project team will integrate an advanced solar receiver, heat exchanger, and thermal energy storage system, using a test solar collector field, for future integration with a high-efficiency power block. The team will also develop new methods and tools for system analysis, operations optimization, laboratory testing and performance characterization, and energy storage. If selected to move on to the third phase, the team will validate the operation of the system and its next-generation components so that utilities can confidently adopt the system.


Brayton Energy aims to create a CSP system that will be cost-effective, reliable, and transferrable to the commercial space. All components and subsystems developed in this program will be designed for production-level manufacturability, helping to minimize capital costs. If successful, this project would show the reliable integrated operation of all components relevant to thermal transport and thermal storage for a high-temperature CSP system. It would prove the ability of a receiver to work with a low-thermal-conductivity fluid, demonstrate the viability of an indirect storage system that must be accessed through a heat exchanger, and show the manageable energy loss related to moving a high-temperature gaseous fluid throughout the system.