Changjiang Unit 4 Completes Cold Functional Tests, Advancing Towards Commissioning

Cold Functional Tests Conclude for Changjiang Unit 4

Changjiang Unit 4, a Hualong One reactor, has successfully completed its cold functional tests. This milestone signifies the unit's official entry into the commissioning phase, paving the way for subsequent hot testing, fuel loading, and eventual grid connection. Cold functional tests are designed to confirm the proper installation and operational readiness of safety-critical components and systems under cold conditions. These tests involve operating reactor systems in conjunction with auxiliary systems for the first time.

The primary objective of these tests is to verify the leak-tightness of the primary circuit and its components, including pressure vessels, pipelines, and valves within both the nuclear and conventional islands. The process also includes cleaning the main circulation pipes. During the tests, the primary loop system's pressure was progressively increased through several stages, reaching a maximum of 22.3 MPa, with systematic assessments conducted at each pressure level.

Project Overview and Site Development

Two Hualong One reactors, Changjiang units 3 and 4, are under construction as part of the second phase of the Changjiang plant. First concrete for Unit 3's nuclear island base slab was poured in March 2021, followed by Unit 4 in December of the same year. The total estimated investment for Changjiang Phase II is CNY40 billion (USD5.9 billion).

Changjiang Unit 3 achieved first criticality on July 10 and was connected to the grid on August 1. Both units are projected to be fully operational by early 2027. The Changjiang nuclear site currently operates two CNP-600 pressurized water reactors, Changjiang 1 and 2, which began commercial operation in 2015 and 2016, respectively.

In addition to the Hualong One units, construction began in 2021 on a demonstration ACP100 small modular reactor at the Changjiang site. This multi-purpose 125 MWe pressurized water reactor, also known as the Linglong One, is designed for various applications including electricity generation, heating, steam production, and seawater desalination. It is currently undergoing pre-commissioning tests. Hainan Province's energy policies, published in 2019, designate nuclear power as the primary electricity source for the island.

West Bengal to Modernize Power Grid with Underground Networks

The state government of West Bengal plans to implement underground power distribution networks in 16 towns, including tourist areas such as Darjeeling, Kalimpong, Kurseong, and Mirik. The project, estimated at ₹ 2,014 crore, will be entirely financed by the Centre through its Special Assistance to States for Capital Investment (SASCI) scheme. West Bengal State Electricity Distribution Co Ltd (WBSEDCL) will issue the tender before Durga Puja, with construction anticipated to start in January 2027 and conclude by December 2028.

This initiative marks the first instance of 100% central funding for underground power distribution networks in the state, aiming to enhance power quality and supply reliability without burdening the state exchequer. The underground system is also expected to mitigate accidents from overhead wires and reduce power theft. WBSEDCL has previously completed similar projects in Chandernagore, Rajarhat, Kharagpur, and Baruipur, with ongoing work in Asansol and Siliguri, under a World Bank-funded program to strengthen and modernize the state’s electricity infrastructure.

SMRs aren't just creating new reactors.

SMRs aren't just creating new reactors.
They're rebuilding industrial capability.

Rolls-Royce SMR has confirmed that Siemens Energy will manufacture key steam turbine components for the first three UK SMRs at its Newcastle facility.

At first glance, this looks like another supplier announcement.

In reality, it signals something much bigger.

The Newcastle site has been manufacturing energy equipment since 1889. It built the steam turbine for Calder Hall, the world's first commercial nuclear power plant, and will now manufacture turbines for the next generation of UK nuclear projects.

The announcement is expected to support more than 550 jobs, strengthen domestic manufacturing and help establish a UK-led supply chain for both national deployment and future exports.

For the supply chain, this is an important reminder:
SMR programmes are not only about reactor technology. They are also about rebuilding the industrial ecosystem needed to manufacture, assemble and support them at scale.