The use of high temperature (>1000°C) thermal energy storage (TES) would facilitate better heat management in energy intensive processes and reduce energy intermittency when implemented into concentrated solar power or other renewable energy sources. At these high temperatures, radiation becomes an important mode of heat transfer. To take advantage of this effect, greenhouse gases such as carbon dioxide (CO2) and steam (H2O) were investigated, first alone and then as a mixture, as potential heat transfer fluids (HTFs) due to their ability to absorb radiation for TES compared to nitrogen (N2). These gases, CO2 and steam, were selected for testing since methane combustion is a common energy generation technique. To investigate this, a novel experimental setup was designed to measure the temperature of CO2, N2, and steam with a moving thermocouple as the gases were heated up through a tube to 1400°C. The moving thermocouple was calibrated to operate along a 12-inch zone and allows for temperature measurements to be taken continuously at any height as the gas is heated. The experimental setup is explained in depth and interval lengths are examined to determine an optimal temperature rate of charge for use in experimental accuracy and repeatability. Because radiation is significant at ultra-high temperatures, greenhouse gases used as HTFs for TES have the potential to enhance heat transfer from the gas to the thermal storage material (TSM). This presentation will include a description of the unique well-insulated experimental setup, the experimental results, and application in future engineering processes.
