戦前日本の郡部において電灯普及は急速に進展した。大規模発電所を中心とする都市型電力システムとは対照的に、多くの地域で、地元の水資源を活用した発電力100kw以下の小規模事業体による、いわば小規模分散型の電力システムが確立していた。ただし電気が普及していたとはいえ、その用途は照明に限定されていた。さらに需要家当たりの電灯数は２−４灯と、現在と比べると少なかった。この原因は当時電力使用量を基準とする従量料金が少なく、燭光数と取付数を基準とした定額料金が大勢を占めていたことにある。
Prior to the Second World War, there was a rapid progress on electric lighting in rural areas of Japan. In contrast to the urban electricity system which was centered around large-scaled electric power plants, so-called "small-scaled distributed electricity systems" by small-scaled operators with generating capacity under 100kw utilizing local water resources were established in many areas. However, even though electricity was prevalent, use of electricity was limited to lighting purposes. Moreover, the number of lighting lamps per customer household was 2 to 4, low compared to the present day. It was because metered rates based on electricity usage were rare at that time, and flat rates based on the number of lighting lamps and fixtures were much more common.
