Fellow, affiliation:
01/2023-12/2023: Department of Applied Physics and Department of Electrical Engineering, Eindhoven University of Technology
10/2022-09/2024: Chair for Energy and Environmental Process Engineering, University of Siegen
Impact of mechanisms of reversible gas-solid reactions on the bulk properties of materials in devices for thermochemical energy storage and heat conversion -ReAct TCS –
Dr. Sandra Afflerbach
The transition to a sustainable, efficient but also affordable future energy supply is in the focus of politics and research around the world. Mature storage technologies are required to compensate for the temporal discrepancy between energy generation from renewable resources and energy demand. Also, the implementation of industrial waste heat flows could significantly contribute to a more efficient energy utilization and reduction of CO2 emissions.
Within this field, thermal energy storage devices are intensively researched.
While sensible storage materials store energy proportional to the temperature to which they are heated during a storage period, latent storage media undergo a phase change with the stored energy being proportional to the respective heat of fusion. In order to prevent unintended discharging during the storage period, in both cases costly insulation is needed and the achievable storage periods are rather short. In contrast, thermochemical storage materials allow for a loss free and long-term cold storage since charging and discharging is facilitated by reversible chemical gas-solid reactions. Thereby, a solid starting material is endothermally decomposed into a solid and a gaseous reactant, which are separated during the storage period. When both reaction partners recombine exothermally, the energy is released and the material is ready for the next storage cycle. The energy density is up to five times higher compared to latent storage media. However, thermochemical storage systems are yet the less developed.
The project aims to systematically increase the technological readiness of thermochemical systems by fundamental research addressing application-oriented issues in a cross-scale approach: At first, new thermochemical reaction systems are about to be identified and characterized according to their reaction mechanisms by investigation in lab-scale experiments. Based on these results, the impact of the respective reaction mechanisms on the bulk properties evolving during repeated cycling is studied in reactor-scale. Finally, feasible strategies for stabilization of bulk properties can be derived, allowing for an efficient and persistent mass and heat transport during repeated charging and discharging in technical scale.