[en] Kyushu Electric Power CO., Inc. provides electric power throughout Kyushu region that is located in the southwest of the Japanese Archipelago. We have been operating two nuclear power stations whose power generating capacity accounts for 25% of our gross power generating capacity of 5,258 MW. 45% of our gross power-generating amount is being provided with nuclear power generation. Genkai Nuclear Power station is located in the northwest of Kyushu and is the first plant that we introduced. At Genkai we have been operating four reactors since we started operating the first reactor in 1975. Genkai nuclear power station whose nuclear generating capacity is 3,478 MW is the largest one in Kyushu. The appropriate tests and inspections ensure the integrity of equipment for nuclear power plants, but we are planning to replace the main component (reactor vessel closure head for unit 1 and 2, steam generators for unit 2, etc.) in order to improve further the reduction of radiation exposure and the reliability of equipment. This time we introduce the work background and contents and so on about the replacement plan of main component for Genkai unit 1 and 2 whose outage is scheduled in March 2001. (author)