Hitachi Energy, a global leader in electrification, has been selected by China General Nuclear Power Group (CGNPC) to provide replacement and upgrade solutions for its aging installed gas-insulated switchgear (GIS), the critical power transmission and distribution equipment at the Daya Bay Nuclear Power Station. The project aims to enhance the plant’s operational safety and reliability, supporting a stable and low-carbon supply of clean energy across the Guangdong-Hong Kong-Macao Greater Bay Area.
Daya Bay Nuclear Power Station in Shenzhen, Guangdong, is mainland China’s first large-scale commercial nuclear plant and a key energy source for the Greater Bay Area. Since 1994, it has generated nearly 15 billion kWh annually, with about 80 percent supplied to Hong Kong—accounting for roughly a quarter of its electricity consumption. Its safe, reliable operation remains critical to regional energy security.
However, decades of continuous operation combined with rising energy demand are placing increasing strain on the reliability of critical equipment. This upgrade project focuses on the 500 kilovolts (kV) GIS that has been in service for more than 30 years. As a critical link connecting the power station to the grid, the GIS plays an essential role in power control and protection.
As part of the project, Hitachi Energy will leverage its extensive service experience with high-voltage products to develop retrofit solutions tailored to the existing customer infrastructure. Given the scale and technical complexity, the replacement of all 15 bays will be carried out in phases over an estimated eight-year period. This work will be aligned with nuclear and grid maintenance windows to ensure an uninterrupted power supply throughout the process. It is considered one of the most complex GIS retrofit projects, with demanding commercial and contractual requirements, including nuclear liability, while meeting the plant’s stringent standards for reliability, availability, and operational stability.
“We are pleased to participate in the upgrade project at the Daya Bay Nuclear Power Station. The systematic replacement of core high-voltage switchgear that has been in service for more than 30 years is a critical measure to ensure the long-term resilience operation of this ‘cornerstone’ of energy supply for the Guangdong–Hong Kong–Macao Greater Bay Area,” said Liu Tianquan, Local Service Business Unit Manager in China, Hitachi Energy. “Leveraging our advanced technologies and full lifecycle service expertise, Hitachi Energy will fully support the safe life extension and efficient operation of the power station, contributing to high-quality low-carbon development in the region.”
Against the backdrop of growing global electricity demand and accelerating energy transition, nuclear power continues to play a vital role as a stable, efficient, and low-carbon energy source. It is increasingly important for ensuring energy security and supporting emerging power demand, such as AI-driven data centers. China now has one of the world’s largest nuclear power fleets and is entering a new stage of high-quality development. In this context, upgrading aging equipment has become a fundamental pillar in ensuring the long-term safe and reliable operation of nuclear power plants.