# Is China's Changjiang Nuclear Site Becoming Hainan's Primary Power Source?

**CNY 40 billion ($5.9 billion).** That is the total estimated investment behind Changjiang Phase II, and Unit 3 — the first Hualong One (HPR1000) reactor at the site — has now entered commercial operation, China Huaneng confirmed on 17 September 2026. The unit achieved [nuclear criticality](https://smrintel.com/glossary/criticality) on 10 July 2026 and was connected to the grid on 1 August 2026, with commercial operation declaration following today. Its twin, Unit 4, is scheduled to reach full operational status in early 2027.

The milestone carries institutional significance beyond the reactor itself: Changjiang 3 is the first large-scale power reactor that China Huaneng Group has constructed and operated as the *controlling* stakeholder, holding a 51% share in the project. For China's nuclear buildout, it signals that state-owned energy conglomerates beyond the traditional reactor builders — [China National Nuclear Corporation](https://smrintel.com/companies/cnnc) and China General Nuclear — are maturing into full-cycle nuclear operators. The Changjiang site now hosts two operating CNP-600 PWRs (Units 1 and 2, commissioned in 2015 and 2016), two HPR1000 units under Phase II, and a demonstration ACP100 SMR that is currently undergoing pre-commissioning tests.

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## HPR1000 at Changjiang: Key Milestones and Timeline

First concrete for Unit 3's nuclear island base slab was poured in March 2021 — a relatively clean construction record given the global supply chain disruptions of that period. Unit 4's first concrete followed in December 2021. The roughly five-and-a-half-year span from first concrete to commercial operation for Unit 3 is consistent with recent HPR1000 construction times at other Chinese sites, though Western developers should be cautious about direct comparisons: China's construction ecosystem, regulatory cadence, and supply chain integration differ substantially from FOAK conditions in Europe or North America.

Upon completion of both units, the Phase II project is expected to generate 18 billion kilowatt-hours of electricity annually, according to Liu Bin, general manager of Huaneng Hainan Changjiang Nuclear Power Company Ltd, as quoted by *China Daily*. Liu also cited projections of replacing more than 6.32 million metric tons of standard coal and reducing CO₂ emissions by approximately 11.6 million tons per year. These are operator-reported figures and should be understood as design-basis projections tied to assumed [capacity factor](https://smrintel.com/glossary/capacity-factor) performance — actual generation will depend on grid dispatch requirements and outage schedules as the units mature.

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## Hainan's Nuclear Ambitions: A Strategic Island Energy Play

Hainan Province's energy policy trajectory is worth tracking independently of the reactor technology involved. Energy policies published in 2019 by the Hainan Province Development and Reform Commission explicitly designate nuclear power as the primary electricity source for the island, which has a population of close to 10 million. That is an unusually direct policy commitment to nuclear [baseload power](https://smrintel.com/glossary/baseload) at the provincial level — most Chinese provincial energy plans treat nuclear as one component of a diversified mix.

The strategic rationale is straightforward: Hainan is an island with constrained transmission interconnection to the mainland grid, making domestic generation reliability a priority. Nuclear's high capacity factor and firm output characteristics suit that profile far better than variable renewables alone. The Hainan Free Trade Port — a major national economic development initiative — adds demand-side urgency. Liu Bin's comment explicitly linked Phase II output to "anchoring the construction of the Hainan Free Trade Port," signaling that the reactor buildout and economic development planning are deliberately synchronized.

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## The ACP100 Angle: China's SMR Progress at the Same Site

The Changjiang site is also home to what may be the world's most advanced small modular reactor construction project: the demonstration ACP100 (marketed internationally as the Linglong One), a 125 MWe multi-purpose PWR developed by [China National Nuclear Corporation](https://smrintel.com/companies/cnnc). Construction began in 2021, and as of this report the unit is undergoing pre-commissioning tests.

The ACP100's multi-purpose design — capable of electricity production, district heating, industrial steam supply, or seawater desalination — positions it as a direct competitor to several Western SMR concepts currently navigating regulatory processes that are years behind China's construction timeline. The fact that a working demonstration unit is now at pre-commissioning stage, on the same site as two operating conventional PWRs and two newly commissioned HPR1000 units, gives [CNNC](https://smrintel.com/companies/cnnc) an operational learning environment that no Western SMR developer can currently match.

The convergence of HPR1000 commercial operation and ACP100 pre-commissioning at Changjiang makes this site arguably the most data-rich advanced nuclear deployment location in the world right now. Western developers and policymakers who dismiss Chinese construction timelines as non-transferable may be right about the regulatory and industrial context — but they should not be dismissive of the operational data being generated.

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## China Huaneng's Expanding Nuclear Role

The institutional narrative here deserves attention from energy investors and utility executives. China Huaneng's controlling stake in Changjiang Phase II represents a deliberate diversification of China's nuclear ownership structure away from the CNNC/CGN duopoly. Huaneng already holds a controlling stake in the High Temperature Gas-Cooled Reactor-Pebble-bed Module ([HTR-PM](https://smrintel.com/glossary/htgr)) demonstration plant at Shidaowan in Shandong Province, which entered commercial operation in December 2023, according to the source material. Minority stakes in additional units round out a portfolio that is now clearly tilted toward operational rather than merely financial nuclear exposure.

For Western utility executives evaluating nuclear as a corporate strategy — whether through direct ownership, PPAs with new build projects, or technology licensing — Huaneng's trajectory offers a case study in what deliberate, decade-long commitment to nuclear capacity building looks like at the operator level.

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## Key Takeaways

- **Changjiang Unit 3** (HPR1000) entered commercial operation on 17 September 2026, following first criticality on 10 July and grid connection on 1 August 2026.
- **Phase II total investment** is CNY 40 billion ($5.9 billion), with China Huaneng holding a 51% controlling stake — its first as a nuclear operator at this scale.
- **Unit 4** is scheduled for commercial operation in early 2027; combined Phase II output projected at 18 billion kWh annually.
- **The ACP100 SMR** (125 MWe, Linglong One) at the same site is in pre-commissioning, making Changjiang the most operationally dense advanced nuclear site currently active.
- **Hainan's 2019 energy policy** designates nuclear as the island's primary electricity source — an unusually direct provincial commitment driven by island grid constraints and Free Trade Port development.
- China Huaneng's operational nuclear portfolio — now including a controlling stake in both an HPR1000 and the HTR-PM — signals meaningful diversification of China's nuclear operator base beyond CNNC and CGN.

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## Frequently Asked Questions

**What is the Changjiang Unit 3 reactor type?**
Changjiang Unit 3 is a Hualong One (HPR1000) pressurized water reactor, China's third-generation domestic reactor design. It is the first of two HPR1000 units being built as Phase II of the Changjiang nuclear power plant in Hainan Province.

**When did Changjiang Unit 3 achieve criticality and commercial operation?**
According to World Nuclear News, the unit achieved first criticality on 10 July 2026, was connected to the grid on 1 August 2026, and entered commercial operation on 17 September 2026.

**What is the ACP100 reactor at Changjiang and how advanced is it?**
The ACP100, also known as Linglong One, is a 125 MWe multi-purpose small modular reactor developed by China National Nuclear Corporation. Construction at the Changjiang site began in 2021 and the unit is currently undergoing pre-commissioning tests — making it one of the most advanced SMR construction projects in the world.

**Why is Hainan Province prioritizing nuclear power?**
Hainan is an island province with limited grid interconnection to mainland China, making locally generated firm power a strategic priority. Provincial energy policy from 2019 designates nuclear as Hainan's primary electricity source. The Hainan Free Trade Port development program adds further demand-side pressure for reliable, low-carbon generation.

**What is China Huaneng's role in Changjiang and why does it matter?**
China Huaneng holds a 51% controlling stake in Changjiang Phase II, making Changjiang Unit 3 the first large-scale reactor it has constructed and operated as controlling stakeholder. This marks meaningful expansion of China's nuclear operator base beyond the traditional CNNC and China General Nuclear duopoly, with implications for how nuclear project financing and operation may be structured in future Chinese and potentially export-market projects.