The proposed Palermo 1 architecture is a single shaft, gas-generator cycle turbopump. This is classed as an open cycle turbopump as the Preburner exhaust exiting the turbine is not routed back into the main combustion chamber. The single shaft design couples both centrifugal pumps onto the same shaft as the turbine. These pumps draw in low pressure propellants and output them at a higher pressure suitable for the Ceres 1 engine. Small amounts of propellants are tapped off after exiting the pumps and are fed into the Preburner. The Preburner is a bipropellant rocket engine that provides high pressure driving fluid to the turbine, which in turn drives both pumps on the shaft.