Key Takeaways:
Advanced nuclear reactor companies reached critical operational milestones in July, sending the Range Nuclear Renaissance Index up 12 percent and drawing investor attention to the NUKZ ETF.
China's Hualong One reactor at Changjiang achieved first criticality on July 10, while Slovakia's Mochovce 4 completed fuel loading — two milestones that pushed the Range Nuclear Renaissance Index up 12 percent in July and lifted the NUKZ ETF as investors rotate into clean baseload power plays.
"The global push for reliable baseload power is driving rapid development in the advanced reactor market," said a spokesperson for the NUKZ ETF issuer, adding that key companies are hitting major operational and criticality milestones.
China National Nuclear Corp.'s Changjiang Unit 3, a 1,100 MWe Hualong One pressurized water reactor, reached first criticality at 18:00 local time on July 10, marking the moment the reactor sustained a controlled fission chain reaction. The milestone paves the way for grid connection and commercial operation, with Unit 4 expected to follow in early 2027. In Slovakia, Slovenské elektrárne completed fuel loading at Mochovce 4, a 471 MW VVER-440 unit, and aims to deliver first electricity by the end of summer 2026. When fully operational, the unit will push nuclear's share of Slovakia's electricity consumption to 77.5 percent, the highest proportion for any country.
The NUKZ ETF, which tracks the Range Nuclear Renaissance Index, has benefited from a rotation into nuclear supply chain stocks as AI data center energy demand drives utilities and hyperscalers to secure 24/7 carbon-free power. The fund holds positions in uranium miners, reactor developers, and engineering firms across the nuclear fuel cycle.
China and Slovakia Lead the Operational Wave
Changjiang Unit 3 is the first of two Hualong One reactors being built during the second phase of the Changjiang Nuclear Power Plant in Hainan Province. The two units represent an investment of about CNY 40 billion ($5.9 billion) and are expected to be fully operational by early 2027. The Hualong One, China's flagship Generation III pressurized water reactor, incorporates active and passive safety systems and a 60-year design life, according to CNNC.
Slovakia's Mochovce 4 represents the completion of a project that began in 1986 but stalled for years. Construction restarted in the late 2000s at an estimated cost of EUR 6.7 billion ($7.6 billion). Unit 3 entered commercial operation in October 2023, and Unit 4 is now in the start-up phase, with strength tests, pre-critical checks, and the first controlled fission chain reaction ahead before grid connection.
Nuclear Supply Chain Draws Investor Attention
The operational milestones come as the nuclear energy supply chain gains visibility among institutional investors. The NUKZ ETF provides exposure to companies involved in uranium mining, fuel fabrication, reactor component manufacturing, and engineering services. The fund's July performance reflects growing conviction that nuclear will play a role in meeting surging electricity demand from AI data centers, which reached about 29.6 gigawatts of power capacity in the US by the fourth quarter of 2025, according to the Stanford AI Index report.
The US Department of Energy has also stepped in with financing. In June 2026, it announced $17.5 billion in American Nuclear Supply Chain Loans to accelerate deployment of 10 large-scale commercial reactors. Loan guarantees, however, carry risks: a 2008 Congressional Budget Office report warned that such incentives can cause recipients to invest in excessively risky projects because they do not bear all the cost of failure.
For investors, the NUKZ ETF offers a diversified bet on nuclear's re-emergence, but the timeline remains long. New reactor construction in the US typically takes a decade or more, and cost overruns have plagued recent projects. The Vogtle expansion in Georgia, the only large reactors completed in the US in recent years, ended up costing more than $36 billion — more than double the initial estimate. Investors should weigh the thematic tailwind from AI-driven power demand against the execution risk inherent in nuclear construction.
This article is for informational purposes only and does not constitute investment advice.
