Hizen

Hizen is a Japanese word. It can be written in Kanji, as '肥前', which is the name of a region in modern Kyuushuu.
The name Hizen is derived from '火の国' which literally means Fire Nations. The reason for such a name is the high number of volcanoes in that area.
The word 'Fire' can be seen as to mean 'energy' in the Japanese language.

I went to the Hizen region during summer, it was so hot I could barely get out of the Hotel.