To facilitate the installation and reduce the running cost by providing a power circuit constituted by adding a storage battery to a power source means for induced electric power from a power transmission line, solar energy, and wind power generation and connecting them in parallel.

A power source board 2 which contains the circuit parts of the airplane warning light is installed on a steel 1 for power transmission lines and two solar cell panel 4 on which solar cells 3 are stuck are provided; and further two light sources 5 for the air hazard lamp are provided. The power source board 2 is fitted with the wind mill 7 of a vertical shaft type wind power generator 6. An overhead earth-wire 8 is strung on the steel tower 1 and fitted with current transformers 9 at two placed. The current transformers 9 are so constituted that an induced current flows to the overheat earth-wire 8 with a power transmit current flowing to the power transmission line to generate electromotive forces at the coils. Those power source means 3a, 6a, and 9a charge electricity during power transmission line operation, during daytime, or when wind blows and the airplane warning light illuminates at nighttime.