Every load is just connected to the chassis of the vehicle. Simply grounding amps to the chassis will result in load seen by the battery. But that alone won't fully engage the alternator output since it varies quite wildly and total load isn't one of the "triggers".
Simply put, the alternator output will vary wildly, as noted above. Keeping the alternator voltage above 13.9VDC can be accomplished by using the wipers, keeping the headlights on, or inducing a "current sensor malfunction", the latter of which is not described further. I don't know if that means an open circuit or short circuit will result in a "malfunction". I suppose someone could just unplug the sensors wires to see what happens. I imagine it will throw a code.
https://www.hallsensorchip.com/news/...effect-sensor/
https://www.allegromicro.com/ja-jp/i...urrent-sensing