Chubu Electric Submits N-Plant Data Fraud Report

Jiji Press

15:50 JST, March 31, 2026

Tokyo, March 31 (Jiji Press)—Chubu Electric Power Co. submitted a report to nuclear regulators on Tuesday detailing earthquake risk data fraud involving its Hamaoka nuclear power station in Shizuoka Prefecture, central Japan.

The Nuclear Regulation Authority had given the company until Tuesday to submit a report on the facts about the data fraud. The NRA will receive reports on the causes of the fraud without any deadline.

Chubu Electric has said that it selected a representative seismic wave using methods different from those presented to the NRA at least since 2018. In addition, the company deliberately chose seismic waves other than average values.

Those irregularities raised suspicions that the company underestimated the seismic ground motions that the nuclear plant could experience.

The NRA learned of the data fraud through an external tip in February 2025, and Chubu Electric made public the misconduct on January this year.

The agency’s on-site inspection of the company found that there was almost no record of setting up the seismic ground motions and the lack of necessary operation plan.