Depends on what you consider a machine, the largest power grids are more powerful. Though those are arguably multiple devices acting together not a single device. Most powerful local machine that’s close to steady state is probably Three Gorges Dam at 22.5 GW.

Starship is like a top drag racer where it’s quickly damaging itself in normal operation, but it’s the most powerful local machine that can last for over a minute.

However, there’s a lot of pulsed devices that briefly get to much higher energy levels like artillery or experiments that charge capacitor banks for massive discharges like Z machine which briefly hits 300TW.