Proceedings Article | 7 June 2024
KEYWORDS: Solar energy, Oxygen, Hydrogen, Photovoltaics, Solar cells, Batteries, Hydrogen energy, Air temperature, Power consumption, Molecules
The U.S. Army’s climate and modernization priorities are driving significant improvements in the U.S. Army’s capabilities, while multi-domain operations (MDO) are driving a need for substantial improvements to legacy and future systems that support a more comprehensive operational range and can be pushed harder, faster, and for longer periods. For the foreseeable future, the U.S. Army and its allies will rely on devices that utilize some form of the internal combustion engine (ICE). In the interim, however, hybrid technology has received much interest as ICEs can be combined with other dissimilar energy generation, transmission, load, and storage possibilities, including fuel cells, photovoltaics, and decaying radioisotopes. Fundamentally making a hybrid device a self-contained energy network or microgrid. This paper investigates the operational use of a hydrogen fuel cell-supported tactical energy network that includes photovoltaic arrays and electrochemical energy storage. Energy harnessed from the solar arrays can be used to split water molecules, forming hydrogen and oxygen while energy demand is low; conversely, if energy demand is high, the fuel cell may also supply energy. Fuel cell systems have reduced acoustic and thermal signatures compared to ICEs, making such technology an ideal candidate for civilian and military applications, especially where water is abundant and can be dependably harvested. Hydrogen production and water consumption of a fuel cell are analyzed subject to three characteristic sky conditions: clear, partly cloudy, and overcast sky conditions. Two optimization strategies were explored and used to optimally control the energy networks to extend the energy network’s operation, which was limited by the water reservoir and atmospheric conditions.