Session: 07-04: Modeling of Thermal Energy Storage and Receiver Systems

Paper Number: 166045

166045 - Thermal Energy Storage and Exchange With Integrated Rotating Media Transport (Sandewirm): An Overview 

Abstract: 

Solid particles are an attractive media option for Thermal Energy Storage (TES) systems; most candidate materials being considered are robust, inert, non-toxic, and capable of operation over a wide range of temperatures, from very low (cryogenic) to very high (1,500 C or more). Media costs can be very low (less than $100 per ton for silica sand), and heat exchangers specifically designed for particle-to-gas operation have undergone extensive development in recent years, further improving the viability of these systems. Lastly, these materials flow freely … but only in the direction of gravity, which necessitates additional particle handling to enable fully cyclic operation. Emerging solid particle TES systems typically leverage conventional mining and materials-handling technologies, but integrating them with high temperature particles for use in scenarios that require high reliability, low capital cost, and low operating power has proven challenging.

A novel solid-particle-based thermal energy storage system that consolidates storage, heat exchange, and media transport into a single moving part is being developed through funding by the US Department of Energy. Within this 3-year program detailed engineering analyses – including analytical, FEA and CFD models, as well as Discrete Element Modeling – are being coupled with rapid hardware demonstrations of the technology through 3D-printed visualization prototypes, a 0.5 MWht lab-scale test unit, and a deployable 5.0 MWht pilot-scale system. A methodology developed under the DoE’s Gen3 CSP program will be leveraged to optimize approximately two dozen highly-interdependent design variables, thereby generating the lowest cost-of-storage configurations for multiple applications – including several benchmark full-scale systems as well as the Pilot-Scale system.

This system embodies many advantages as compared to conventional systems, including (a) the elimination of any particle transport devices with moving parts (bucket elevators, augers, skip hoists), (b) containment of all particle media within a single vessel, (c) minimal contact area between charged (hot) and discharge (cold) particles, (d) operating power requirement that are 80% less than that of conventional particle lift, (e) a single high-effectiveness heat exchanger for both charge and discharge operation, and (f) ability to match power demands across a wide range of applications. These features cumulatively mitigate many of the challenges associated with contemporary and emerging energy storage systems, including capital cost, reliability/availability, particle-induced wear and abrasion, particle attrition, operating power, maintenance costs, and heat losses.

This presentation will provide a detailed overview of the proposed technology, as well as outlining the accelerated development program that proposes to advance the technology from TRL 3 up through TRL 7 within 3.5 years. The encouraging results of Performance and Techno-Economic analyses will be presented, as will the design and plans for lab-scale system testing in Q4 of 2025.

Presenting Author: Shaun Sullivan Brayton Energy

Presenting Author Biography: Shaun Sullivan is the President and a Principal Engineer at Brayton Energy, an Engineering R&D Firm located 45 miles north of Boston. Shaun has worked in the field of cutting-edge energy- systems development for nearly 25 years, specializing in systems, heat transfer, and thermal modeling and analysis. At Brayton he has led projects in hybrid-electric fuel cell systems, concentrating solar power, supercritical carbon dioxide cycles, energy storage, low-emissions and alternatively-fueled combustors, advanced heat exchangers, and combined heat and power solutions. Prior to joining Brayton in 2008 he worked at Ingersoll Rand Energy Systems (now FlexEnergy), a leading manufacturer of small-scale (70 kWe and 250 kWe) turbines for backup, alternatively-fueled, and distributed power generation. Shaun holds an M.S. in Mechanical Engineering from the Massachusetts Institute of Technology (MIT) and a B.S. in Mechanical Engineering from Rensselaer Polytechnic Institute.