Argentina’s Atomic Future: From Legacy Reactors to Next-Gen SMRs

Argentina’s nuclear energy sector plays a vital role in the country’s electricity mix, contributing to energy security and low-carbon power generation. With a history spanning over five decades, the nation has developed a robust nuclear infrastructure, operating three reactors and pursuing ambitious plans for expansion. Let us delve into the current state of Argentina’s nuclear energy sector, its historical development, ongoing projects, and future prospects

Electricity Sector Overview

Argentina’s electricity sector is characterized by a diverse mix of energy sources, with a total installed capacity reaching approximately 43,133 MWe as of 2023. In the year 2022, the country generated around 147 terawatt-hours (TWh) of electricity. Fossil fuels, including natural gas, oil, and coal, accounted for the largest share at 61% of the total generation. Hydropower followed with a contribution of 21%, while wind and solar energy provided 9% and 3% respectively. Bioenergy made up 1% of the mix.

Nuclear energy, although contributing a relatively modest 5% to Argentina’s electricity generation, plays a vital role in the country’s low-carbon energy strategy. It serves as a reliable source of base-load power, ensuring consistent electricity supply irrespective of weather conditions or time of day. The strategic importance of nuclear power is further underscored by its contribution to reducing Argentina’s reliance on fossil fuels. This is particularly significant given the nation’s abundant natural gas and oil reserves, which have historically dominated its energy landscape, and its steadily growing domestic energy demand.

A Snapshot of Argentina’s Nuclear Power

Argentina operates three nuclear power reactors, which collectively generate about 1,641 MWe of capacity:

• Atucha I: A 319 MWe Pressurized Heavy Water Reactor (PHWR) of Siemens design, operational since 1974. In 2001, it became the first PHWR globally to use Slightly Enriched Uranium (SEU), enhancing fuel efficiency.

• Atucha II: A 692 MWe PHWR, also of Siemens design, connected to the grid in 2014 after a prolonged construction period. It significantly boosted Argentina’s nuclear capacity.

• Embalse: A 608 MWe CANDU reactor, operational since 1984, known for its reliability and recent life-extension upgrades.

These reactors are managed by Nucleoeléctrica Argentina S.A. (NA-SA), the state-owned utility responsible for nuclear power operations. Together, they produced approximately 8.0 TWh in 2022, accounting for 5% of the national electricity supply. 

Historical Development

Argentina’s nuclear journey began in the 1950s with the establishment of the National Atomic Energy Commission (CNEA) in 1950, which laid the groundwork for research and development. The country’s first commercial reactor, Atucha I, began operations in 1974, marking a significant milestone in Latin America’s nuclear landscape. The Siemens-designed PHWRs at Atucha are unique, tailored to Argentina’s needs, while the Embalse CANDU reactor reflects international collaboration with Canada.

The nuclear sector faced challenges, notably the delayed completion of Atucha II, which began construction in 1981 but was only commissioned in 2014 due to funding and technical issues. Despite these hurdles, Argentina has maintained a strong commitment to nuclear energy, driven by energy security and the need for low-carbon power.

The CAREM Project: Pioneering Small Modular Reactors 

Argentina is actively pursuing new nuclear capacity to meet growing energy demand and support its climate goals. A flagship project is the CAREM25 reactor, a domestically designed Small Modular Reactor (SMR) developed by CNEA and INVAP. Key features include:

• Capacity: 29 MWe (net) or 100 MWt, suitable for electricity generation, research, or desalination.

• Design: A modular, simplified Pressurized Water Reactor (PWR) with integral steam generators, emphasizing safety and scalability.

• Progress: Construction began in February 2014 at a site near Atucha, with 70% of components manufactured locally. The reactor pressure vessel was contracted in 2013, and completion was targeted for 2021, though delays have pushed this timeline.

• Cost: Estimated at ARS 3.5 billion (approximately USD 446 million in 2013 terms).

The CAREM25 is a pioneering project, positioning Argentina as a potential leader in SMR technology. Its modular design allows for cost-effective deployment in remote areas or for specific industrial applications, aligning with global trends toward smaller, flexible reactors.

Uranium Resources

Argentina possesses moderate uranium reserves, primarily located in Salta, Mendoza, and Chubut, with around 11,000 tonnes of identified recoverable uranium. However, estimates from CNEA suggest prospective resources may reach up to 80,000 tonnes. Mining operations are currently focused on the San Rafael mine (Mendoza), while exploration continues at the Cerro Solo deposit (Chubut).

Although the domestic supply has yet to meet national reactor needs fully, Argentina has developed advanced fuel cycle technologies. These capabilities have enabled exports of nuclear components and services, particularly within Latin America, reinforcing the country’s role as a regional leader in nuclear technology.

Regulation, Safety, and Non-Proliferation

The Nuclear Regulatory Authority (ARN), established in 1994, oversees safety and licensing, ensuring compliance with international standards. Argentina’s nuclear policy is guided by Laws No. 15.336 and No. 24.065, which define electricity generation as a general interest and regulate the sector through the Secretariat of Energy and the National Electricity Regulatory Entity. 

Argentina adheres to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and is a signatory to the Treaty of Tlatelolco (1967), which prohibits nuclear weapons in Latin America. The country has not signed the IAEA’s Additional Protocol, reflecting a principled stance similar to Brazil’s, but maintains robust safeguards through the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC).

Safety measures have been strengthened post-Fukushima, with upgrades to Atucha and Embalse reactors to enhance resilience against natural disasters. The Embalse reactor underwent a life-extension refurbishment in 2016–2019, extending its operational life by 30 years.

Strategic Vision: The Argentine Nuclear Plan

In a decisive move to revitalize Argentina’s nuclear agenda, President Javier Milei recently unveiled the Argentine Nuclear Plan, aiming to re-establish nuclear energy as a cornerstone of the national energy strategy. The initiative includes:

• Phase 1: Construction of a new SMR at the Atucha site to meet rising electricity demand and stabilize supply across the country.

• Phase 2: Development of domestic uranium resources to reduce reliance on imports and potentially establish Argentina as an exporter of nuclear fuel.

• Broader Vision: Positioning Argentina as a global leader in peaceful nuclear innovation, particularly in synergy with emerging sectors such as artificial intelligence. The President highlighted Patagonia’s cold climate as ideal for energy-intensive technologies, advocating nuclear as the only source “efficient, abundant, and rapidly scalable” enough to meet civilization’s energy demands.

Hence, Argentina’s nuclear energy sector is a testament to the country’s technological prowess and commitment to sustainable energy. With three operational reactors, a pioneering SMR project, and robust international partnerships, the nation is well-positioned to expand its nuclear capacity. Despite economic and regional challenges, the government’s renewed focus on nuclear power, coupled with innovations like the CAREM25, signals a bright future. As Argentina navigates its energy transition, nuclear energy will remain a cornerstone of its quest for energy security and environmental sustainability.