✔ 最佳答案
When the aircraft is on the ground, electricity can be provide by two ways:
~ Auxiliary Power Unit (APU), usually in the tail of the aircraft, driving generators to provide electricity
~ Power cable connected from the passenger terminal or ground power cart
When the aircraft is in the air:
~ Normally, each engine drives a generator providing electricity
~ In some cases, such as system failure, the APU will be started in flight to drive its generator
Hope it helps...