Atucha Nuclear Complex: Argentina's Hub of Nuclear Energy
The Atucha Nuclear Complex is a critical pillar of Argentina's energy infrastructure. Located in Lima, Zárate, within the Buenos Aires Province, this facility sits on the right-hand shore of the Paraná de las Palmas River, approximately 100 kilometers from the capital city of Buenos Aires. The complex houses two operational plants and is the site of future expansion, utilizing advanced nuclear technology to support the national power grid.
Both operational units at the complex utilize Pressurized Heavy-Water Reactors (PHWR) of the German PHWR KWU design. These reactors use heavy water for both cooling and neutron moderation—the process of slowing down neutrons to sustain a nuclear chain reaction—and employ a fuel mixture of natural uranium and enriched uranium (0.85% U).
Key Facts
- Atucha I was the first nuclear power plant established in Latin America.
- The complex is operated by Nucleoelectrica Argentina.
- Atucha I and II use Siemens-supplied PHWR technology, distinct from the Canadian CANDU type used at the Embalse plant.
- Atucha II's completion increased Argentina's nuclear energy mix from 7% to 10% in 2015.
- A third unit, Atucha III, is planned as a light water reactor provided by China.
Atucha I: A Regional Pioneer
Known officially as the Central Nuclear Juan Domingo Perón, Atucha I began construction in 1968 and was commissioned in 1974. Its launch marked a historic milestone as the first nuclear power plant in Latin America. Despite its technical success, the plant's early history included a security breach on March 25, 1973, when the People's Revolutionary Army temporarily captured the site and stole several firearms.
Technically, Atucha I possesses a thermal capacity of 1,179 MW th and a nameplate capacity of 362 MW. It delivers electricity at 220 kilovolts to the Argentine Interconnection System, contributing roughly 2.5% of the country's total electricity production as of 2005.
![Atucha Nuclear Power Plant was the first nuclear power plant in Latin America.[1]](/images/81/0a/810a5f3008f43504210b3ee719532afb3d563a2d2217363243bb3577544d8a9a.jpg)
Atucha II: Scaling Up Production
The Central Nuclear Néstor Kirchner, or Atucha II, was designed to be significantly more powerful than its predecessor. Construction began in July 1981 under a contract with Siemens, but the project faced a long hiatus, with work halting in 1994. At the time of its inception, Atucha II featured the largest reactor pressure vessel of any nuclear plant worldwide.
Driven by a natural gas crisis in 2004, the Argentine government reactivated the project in 2005. Following a renewed budget and technical push, the plant reached its first criticality on June 3, 2014, and began producing energy on June 27, 2014. By February 19, 2015, the plant reached 100% power production.
Atucha II is one of the few non-CANDU heavy water reactors ever built and was the final nuclear plant constructed by Siemens before the EPR design. It has a nameplate capacity of 745 MW and a thermal capacity of 2,175 MW th.
Atucha III: The Future of the Complex
In February 2022, Argentina entered an agreement with the China National Nuclear Corporation to construct a third unit. This plant will utilize the Hualong One design, a light water reactor with a gross generation capacity of 1,200 MWe. This represents a shift in technology for the complex, as light water reactors require higher enriched fuel and do not support online refueling.
With an estimated cost of US$8 billion, Atucha III will be the most powerful unit at the site, with a nameplate capacity exceeding that of Atucha I and II combined.
Technical Comparison of Atucha Units
| Feature | Atucha I | Atucha II | Atucha III (Planned) |
|---|---|---|---|
| Official Name | Central Nuclear Juan Domingo Perón | Central Nuclear Néstor Kirchner | Hualong One |
| Reactor Type | PHWR KWU | PHWR KWU | Light Water Reactor |
| Supplier | Siemens | Siemens | CNNC (China) |
| Nameplate Capacity | 362 MW | 745 MW | 1,200 MWe |
| Thermal Capacity | 1,179 MW th | 2,175 MW th | Not Specified |
| Status | Operational | Operational | Contracted |
Frequently Asked Questions
What is the difference between the Atucha reactors and the Embalse plant?
While both use pressurized heavy-water reactor (PHWR) technology, the Atucha plants use the German PHWR KWU design supplied by Siemens, whereas the Embalse plant uses the Canadian CANDU 6 design.
Why was Atucha II delayed for so long?
Construction began in 1981 but was halted in 1994. It remained dormant until 2005, when the Argentine government reactivated the project to combat energy shortages caused by a natural gas crisis.
How does Atucha III differ from the existing units?
Atucha III will be a light water reactor rather than a heavy water reactor. This means it will require higher enriched fuel and will not be capable of online refueling, though it will have a much higher power capacity.
Who operates the Atucha Nuclear Complex?
The complex is operated by Nucleoelectrica Argentina.
What is the significance of Atucha I in Latin American history?
Atucha I is significant because it was the first nuclear power plant to be built and operated in Latin America, beginning operations in 1974.