Kyushu Electric Power Co. says the first four fuel bundles were loaded into the Sendai plant's No. 1 reactor Tuesday. The utility plans to finish loading all 157 fuel bundles Friday ahead of final inspections for an Aug. 10 restart.
Regulators affirmed the safety of two Sendai reactors last September. The second reactor is scheduled to be restarted in October.
All of Japan's more than 40 reactors are offline for repairs or safety checks. Prime Minister Shinzo Abe's government wants to restart as many of them as possible to meet the nation's energy needs and grow the economy.