Reactive metals as energy storage and carrier media: use of aluminum for power generation in fuel cell-based power plants

In recent years, the energy production sector has experienced a growing interest in new energy vectors enabling energy storage and, at the same time, intersectoral energy applications among users. Hydrogen is one of the most promising energy storage and carrier media featuring a very high gravimetric energy density, but a rather low volumetric energy density. To this regard, this study focuses on the use of aluminum as energy storage and carrier medium, offering high volumetric energy density (23.5 kWh L−1), ease to transport and stock (e.g., as ingots), and is neither toxic nor dangerous when stored. In addition, mature production and recycling technologies exist for aluminum. Herein, the performance of power systems driven by aluminum powder in terms of electrical efficiency (η(I)) and round-trip efficiency (RTE) is analyzed. Along with the additional advantages relating to high volumetric energy density, and safety and management aspects, the aluminum-based technology appears to outperform the power-to-power systems based on hydrogen and liquid fuels. © 2020 Karlsruher Institut für Technologie. Published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim