To provide a method in which a cable housing member such as a trough, a conduit or the like is used and in which the cooling efficiency of a power cable can be enhanced without disturbing a long-distance power transmission operation.
A coolant 4 is filled into a gap between a cable housing member 1 and housed power cables 3 in certain sections in the length direction of the cable housing member 1 or over the whole length, cooling pipes 2 are passed through the refrigerant 4, the coolant 4 is cooled directly by the cooling pipes 2, and the power cables 3 are cooled by the cooled refrigerant 4. When the cable housing member 1 is not watertight, it is preferable to internally paste a watertight sheet. When the power cables are laid in a borehole, it is preferable that shielding plates which partition the cable housing member 1 up and down are installed in sections and that the refrigerant is filled independently in the sections partitioned by the shielding plates.
TAKAHASHI KAZUYA
TAKAHASHI KENJI
