Nuclear Power in Mexico

(updated May 2010)

• Mexico has two nuclear reactors generating almost 5% of its electricity.
• Its first commercial nuclear power reactor began operating in 1989.
• There is some government support for expanding nuclear energy to reduce reliance on natural gas.

Mexico is rich in hydrocarbon resources and is a net energy exporter. The country's interest in nuclear energy is rooted in the need to reduce its reliance on these sources of energy. In coming years Mexico will increasingly rely on natural gas.

Energy growth was very rapid in the decades to the late 1990s, but then levelled off for a few years.  From about 2007 electricity demand is expected to grow again at an average rate of almost 6% a year.  In 2007, 257 billion kWh was generated.  The electricity supply is quite diverse, with gas supplying 126 TWh (49%), oil 52 TWh (20%), coal 32 TWh (12.5%) and hydroelectric dams 27 TWh (10.5%) in 2007.  Per capita power use is about 1800 kWh/yr.

In 2009 Mexico got about 10 billion kWh net from nuclear, about 4.8% of the electricity used.

Of total 54 GWe capacity in 2006, nuclear was 1.37 GWe (gross), hydro 10.7 GWe, geothermal 960 MWe and the balance fossil fuels. 

Nuclear industry development

Mexico's interest in nuclear energy was made official in 1956 with the establishment of the National Commission for Nuclear Energy (CNEN). That organisation took general responsibility for all nuclear activities in the country except the use of radioisotopes and the generation of electric power. The Federal Electricity Commission  (CFE), one of the two state-owned electricity companies, was assigned the role of future nuclear generator.

Preliminary investigations to identify potential sites for nuclear power plants were begun in 1966 by CNEN and CFE and in 1969 CFE invited bids for proven power plant designs with a capacity of around 600 MWe. In 1972 a decision to build was made, and in 1976 construction began at Laguna Verde on two 654 MWe General Electric boiling-water reactors (BWRs).

Although Mexican industry did not supply major components for the Laguna Verde plant, Mexican companies undertook the civil engineering work and Mexican staff maintain the reactor and train to operate it at CFE's simulator.

CNEN was later transformed into the National Institute on Nuclear Energy (INEN), which in turn was split in 1979 into the National Institute of Nuclear Research (ININ), Mexican Uranium (Uramex) and the National Commission on Nuclear Safety and Safeguards (CNSNS). Uramex's functions were taken over by the Ministry of Energy in 1985.

Operating Mexican power reactors

In February 2007 CFE signed contracts with Spain's Iberdrola Engineering and also Alstom to fit new turbines and generators to the Laguna Verde plant at a cost of US$ 605 million.  The main modifications consist of a turbine and condenser retrofit and the replacement of the electric generator, main steam reheater and the feedwater heater.  They will then produce 20% more power - about 285 MWe to give 1634 MWe for both. With approval from the CNSNS, the reactors are being uprated progressively from 2008 to 2010.  As a first step, 11.6 MWe uprates to both units were achieved in 2007 through better flow control. 

High-level government support exists for an expansion of nuclear energy, primarily to reduce dependence on natural gas, but also to cut carbon emissions - the country's energy policy calls for increasing carbon-free power generation from 27% to 35% of total. The CFE in may 2010 had four scenarios for new power generation capacity from 2019-28, ranging from a heavy reliance on coal-fired power plants to meet growing demand, to a low-carbon scenario that calls for big investments in nuclear and wind power. Under the CFE's most aggressive scenario, up to ten nuclear power plants would be built so that nuclear energy supplied nearly a quarter of Mexico's power needs by 2028, which would allow the country's carbon emissions from power generation to remain virtually unchanged from 2008 despite projections of substantially higher demand. An earlier proposal was for one new nuclear unit to come on line by 2015 with seven more to follow it by 2025 to bring nuclear share of electricity up to 12% then. Cost studies showed nuclear being competitive with gas at about US$ 4 cents/kWh in all scenarios considered.

In the longer term, Mexico may look to employ small reactors such as IRIS to provide power and desalinate seawater for agricultural use.

ININ have previously presented ideas for a plant consisting of three IRIS reactors sharing a stream of seawater for cooling and desalination. With seven reverse-osmosis desalination units served by the reactors, 140,000m³ of potable water could be produced each day, as well 840 MWe.

Fuel cycle

Since its absorbtion of Uramex, the Ministry of Energy has had responsibility for uranium prospecting, which it delegates to the Mineral Resources Board. Mexico has identified reserves of about 2000 tonnes of uranium but this has not been mined to date.

A uranium milling plant operated on an experimental basis at Villa Aldana, in the Chihuahua region at the end of the 1960s but has now been decommissioned. Tailings were disposed of at Pena Blanca.

Under Mexican legislation, nuclear fuel is the property of the state and is under the control of the CNSNS.

Used nuclear fuel from the Laguna Verde reactors is stored underwater at the site. The storage pools have been re-racked to provide enough space for the reactors' entire lives. About 1000 tonnes of used fuel was there as of 2003. The same strategy is employed with used fuel from research reactors.

Radioactive waste management

The government of Mexico, through the Ministry of Energy is responsible for the storage and disposal of nuclear fuels and radioactive waste irrespective of their origin.

The Energy Ministry is beginning to take administrative and budgetary steps to create a national company to manage its radioactive waste. It is also planning to sign the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management.

An engineered near-surface disposal site for low-level waste (LLW) operated at Piedrera between 1985 and 1987. In that time, 20,858m³ of waste was stored.

A collection, treatment and storage centre for LLW has operated at Maquixco since 1972.

Regulation and safety

The 1984 Act on Nuclear Activities states that the government, through the Ministry of Energy, is responsible for establishing the framework for the use and development of nuclear energy and technology, in accordance with the national energy policy.

The National Commission on Nuclear Safety and Safeguards (CNSNS) is a semi-autonomous body under the authority of the Ministry of Energy which takes the role of regulator. CNSNS is responsible for ensuring the proper application of regulations and safeguards for nuclear and radiation safety and for physical protection of nuclear and radiological installations to ensure public safety.

CNSNS is also responsible for revising, evaluating and approving the criteria for the siting, design construction operation and decommissioning of nuclear installations, proposing the relevant regulations. It has the power to amend of suspend the licenses of nuclear facilities, which are granted on CNSNS approval through the Ministry of Energy.

R&D

The main nuclear research organisation in Mexico is the National Nuclear Research Institute (NNRI). NNRI have operated a 1000kW Triga Mk III research reactor since November 1968.

The University Autonoma de Zacatecas has a subcritical Chicago Modelo 900 assembly used for training, commissioned in 1969.

A Nuclear Cooperation Agreement between Mexico and Canada was signed in 1995 for the exchange of information in R&D, health, safety, emergency planning and environmental protection. It also provides for the transfer of nuclear material, equipment and technology and the rendering of technical assistance.

Non-proliferation

The Mexican Constitution states that nuclear energy may only be used for peaceful uses and this is reiterated in the 1984 Act on Nuclear Activities.

Mexico ratified the Nuclear Non-Proliferation Treaty in 1969 and the Additional Protocol in 2004. It is also party to the 1979 Convention on the Physical Protection of Nuclear Material, ratified in 1988. Furthermore, Mexico is the depository of the 1967 Treaty for the Prohibition of Nuclear Weapons in Latin America (the Tlatelolco Treaty) and has been party to the Treaty since 1967.

Sources:
IAEA 2003, Country Nuclear Power Profiles.
Nuclear Legislation in OECD Countries, Regulatory and Institutional Framework for Nuclear Activities, OECD/NEA, 2003.
Radioactive Waste Management Programs in OECD/NEA Member Countries, OECD/NEA, 2005.
Nuclear Engineering International, October 2004.