Magnetto Ionizing Engine

Powerful electromagnetic plasma engine that converts waste to metholox, then ionizes the atoms to both charge your batteries and provide a whomp of thrust. No solar needs, no RAD needs, no refueling needs, and no waste pollution. Separator for outsourced usage in the same compartments produces raw: sulfides, benzopyyroles, hydrogen, oxygen, and carbon. Most of these elements are funneled through recombination to produce fuel from LOx and Methane, while the rest can be harvested for onboard greenhouse growth, electrolysis, and purification systems for air, fertilizer, medicine compounding, and ensure all pollutants are rendered inert for further reprocessing.

Basically this engine is meant to be able to get you any distance in the cosmos and supply most of the resource needs without having to collect it externally. Your crew goes poo, and the engine revitalizes that waste into all useful compounds once more. Feed your astronauts well, and you might get a message from Andromeda in a few dozen decades. (Given the advancement of superluminous info transfer reaches that potential, of course.)