Production of Synthetic Methane for Aerospace Applications: A Mars Case

With the aim to establish a pioneering colony on Mars, the need for refueling the vector to go back to Earth needs to be fulfilled with locally available resources. Based on the advantages of methane as fuel for aerospace applications, the feasibility of a Sabatier reactor providing this fuel on Mars by exploiting the CO2 naturally present in its atmosphere has been evaluated. Alternative options have been considered to provide H2 by using the proven water reserves on the Red planet, through either electrolysis or an electro-thermochemical cycle. Different powering units based on available nuclear reactors have been compared. After preliminary sizing of the plant based on a revised kinetic model for a Ni/Alumina catalyst, different cases have been considered for heating, heat removal, and powering the system. They were characterized by higher energy integration and thus efficiency, or lower efficiency but more compact design and thus lower mass. The overall feasibility has been considered not from a strictly economic point of view, but assessing a reliable overall mass of the equipment to be delivered through the current Starship loading capacity.