In the second episode of Miss Kobayashi's Dragon maid, we see that Kanna absorbs electricity by turning her tail into some sort of a plug. She also says somewhere that electricity is her source of energy or otherwise she becomes lethargic. But how do Kanna get energy in the dragon world? Should I assume that electricity exist in dragon world? If that is the case, how can she turn her tail into a plug if she exist as a dragon in dragon world? What is the source of energy for Kanna in dragon world? Is it electricity? Does they require any source of energy if they exist in the form of dragons? Below is the picture for context:
