Nuclear power, long on the outs, is fashionable again—this time as an antidote to energy insecurity and global climate change. In Latin America, the current plans for nuclear expansion are ambitious. Argentina and Brazil may seek to double or triple existing nuclear capacity. Mexico may build as many as eight more reactors by 2025. Chile, Venezuela and Uruguay are similarly caught up in the enthusiasm for nuclear energy.

With the exception of Mexico, interest in nuclear power around the hemisphere is driven by a desire to find alternatives to erratic hydroelectric power. Rising electricity demand and prices have also tightened natural gas supplies. Add to this the gas cutoff between Argentina and Chile and the nationalization of Bolivia’s natural gas production in 2006, and it’s easy to understand why the interest in nuclear power as a supplement to risky, tight gas supplies is growing.

Yet the road to nuclear power is long and expensive, and whether it can live up to expectations is unclear.

Today, there are just six nuclear power plants in Latin America—two each in Mexico, Argentina and Brazil. In Mexico and Brazil, nuclear energy supplies 4 percent of electricity generation; in Argentina, it supplies 7 percent.

Can an expansion of nuclear energy in Latin America reduce dependence on the energy produced by fossil fuels or hydropower, as many of its advocates claim? In Mexico, the case is uncertain. Its electricity demand is projected to grow 6 percent annually, far above the 2.6 percent global average and roughly the same as India and China. And even if Mexico builds the eight new reactors, nuclear power will only account for 12 percent of electricity generation and do little to relieve the country’s overwhelming dependence on oil and natural gas (a whopping 86 percent) for its total energy consumption. The reason: nuclear power only produces electricity, whereas oil and natural gas are used for many purposes. Moreover, it is questionable how quickly new reactors could be brought online. Mexico’s first reactor, in Laguna Verde, took twenty years from initial bids to operation.

Argentina also faces high electricity demand. With a supply shortfall anticipated in 2010, most observers expect that the gap will increase considerably thereafter. And like Mexico, Argentina relies heavily on conventional fossil-fuel plants and hydroelectric power. According to an August 2006 announcement by Planning Minister Julio de Vido, Buenos Aires will spend $3.5 billion to refurbish its larger reactor at Embalse (in Córdoba) and complete construction of a third reactor, Atucha II, by 2010. The country’s ambitious plans to build five more reactors by 2023 could double nuclear power’s share of electricity generation. But nuclear power will not solve Argentina’s energy needs. Hydroelectric capacity—of which only about 20 percent is used—will need to expand to meet the country’s annual goal of 40,000 megawatts in electrical (MWe) generation by 2025.

Brazil, too, anticipates building a handful of reactors in the next two decades. Its national energy plan calls for four new nuclear power plants to be built by 2025. In the next 50 years, industry officials have reportedly suggested Brazil’s nuclear capacity could reach 60 GWe (Gigawatt electric) of nuclear capacity. This would require building about 58 more plants—a tall order considering that construction on the next reactor, Angra-3, was delayed two years by environmental concerns. Brazil now relies on hydropower for 92 percent of its electricity production. The idea, according to Francisco Rondinelli, head of Brazil’s nuclear association, would be to diversify at least 30 percent of electricity generation equally into nuclear energy, gas and biomass.

Three other Latin American countries may seek to diversify into nuclear power. Chile, which uses hydropower and imported natural gas, is considering nuclear power to reduce supply vulnerabilities stemming from unpredictable rainfall and reliance on uncertain neighbors—namely, Bolivia and Argentina. But the fact that most of Chile sits on a geological fault line also presents a risk. Even if seismic concerns are somehow overcome, Chile will still face a daunting task in developing the necessary physical and intellectual infrastructure.

Venezuela and Uruguay are also interested in nuclear power but have a long way to go. Venezuelan President Hugo Chávez has sought nuclear cooperation from Brazil, France, Iran, and Russia, but few suppliers appear to be biting, perhaps because Venezuela’s plans are not well defined. Meanwhile, Uruguay, which gets virtually all its electricity from hydropower, has mentioned nuclear power as a future option, but national laws banning nuclear energy would need to be overturned. Moreover, its withdrawal of plans for a natural gas plant in 2005 because of the cost ($200 million) and time of construction (26 months) suggests that a nuclear power reactor, which costs upward of $6 billion and takes at least four to five years to construct, may not be in the cards.

Even without a spurt in nuclear power generation, the expansion of transmission grids between countries could be one potential solution to unpredictable energy supplies. The proposed Central American Electrical Interconnection System (SIEPAC) will connect 1,100 miles (1,770 kilometers) of transmission lines between Central American countries and Mexico. The extension of natural gas pipelines is also possible. And Brazil and Argentina have successfully covered shortfalls by selling each other electricity in off seasons.

Latin America is no exception to a global trend that sees nuclear energy as clean, green and homegrown. But like anywhere else, new nuclear power plants will require major political, financial and public support. The unknown variable now is the current economic crisis. Its anticipated dampening effect could provide breathing room to develop the intellectual support and physical infrastructure required for nuclear power. Or, it could extinguish the nuclear enthusiasm that has been growing for the past few years.

Sharon Squassoni is senior associate in the Nonproliferation Program at the Carnegie Endowment for International Peace.

This article originally appeared in the Winter 2009 issue of Americas Quarterly.