System Analysis and Test Loop Design for the CellFlux Storage Concept

AbstractSystems using air at ambient pressure as a working fluid and solid media like natural stones or bricks as storage materials represent the most cost effective option to store sensible heat at medium and high temperatures. The application of this storage concept also for liquid working fluids like thermal oil or molten salts is the basic idea of the CellFlux storage concept. Here, an intermediate air cycle transfers thermal energy between a heat exchanger and a solid medium storage volume. The development of the CellFlux concept comprises various stages: in the initial phase, options for the main subcomponents are identified and evaluated. The integration concept of the CellFlux storage unit into the power plant is essential for the success of the concept. The size of the heat exchanger strongly depends on the average temperature difference between air and working fluid. The costs for the heat exchanger are power dependent and dominate the total capital costs of the CellFlux storage unit. In order to demonstrate the feasibility of the CellFlux, a storage unit with a storage volume of 30m3 for operation with thermal oil at up to 400̊C was designed