The world is at an energy crossroads: the world’s dependence on fossil fuels is increasingly unsustainable.
Oil and gasoline prices have skyrocketed in recent years, and so have production costs and electricity bills. Global warming is advancing and countries seem unable to meet emission cut targets.
And, as if that weren’t enough, the war in Ukraine highlighted Europe’s energy vulnerability due to its high dependence on Russian gas.
“The time has come for a nuclear renaissance,” French President Emmanuel Macron said recently.
Like Macron — who five years earlier had pledged to cut France’s nuclear energy production by a third — many have shifted their stance on nuclear power, which has long been criticized since the Fukushima accident in 2011.
“There is a change in position against atomic energy around the world, although it has intensified in the last year with the rise in gas prices, and the current crisis was the last straw”, explains the science and Spanish nuclear technology Alfredo García to BBC News Mundo (BBC Spanish service).
Is it possible to replace natural gas, oil and coal?
“Unfortunately, it took a war to show us that we can’t rely so heavily on fossil fuels,” says García. They generate at least two-thirds of the world’s electricity and greenhouse gas emissions, according to different studies by international organizations.
Air pollution from burning fossil fuels caused 8 million deaths in 2018, 1 in 5 deaths worldwide, according to a study by Harvard University (USA).
At current rates, emissions are expected to rise by 14% this decade, undermining the 2015 Paris Agreement targets of reducing global temperature rise to 1.5°C by the end of the century.
The need for an energy model that does not depend on fossil fuels is growing. There are two options available: nuclear and renewable.
Greenpeace believes it is possible to make the transition to energy free from fossil fuels without using nuclear energy.
“Adopting a 100% renewable and efficient energy model is technically possible, economically viable and sustainable”, says Meritxell Bennasar, head of Energy and Climate Change at Greenpeace in Spain.
However, proponents of nuclear power question whether this is feasible: Renewables have limited generating capacity, require large amounts of space and materials, and rely on weather conditions to power the grid.
Substituting nuclear power also has its difficulties: building a nuclear power plant and putting it into operation usually takes 5 to 10 years.
“Changing an energy model is neither easy nor quick and the process must be gradual. Progressive replacement requires electrifying various sectors and making a firm commitment to nuclear and renewable energies, working as a team. The total cost is difficult to quantify, but we would have to carry out the process in less than three decades”, explains García.
How is nuclear energy produced?
Nuclear power plants use atomic fission to produce energy—that is, the splitting of atoms.
When splitting a heavy atom — usually uranium 235 — neutrons are produced and the energy released generates a chain reaction in a fraction of a second.
This releases neutrons, gamma rays and large amounts of energy. The intense heat is then used to raise the temperature of the water and produce steam. This steam then spins turbines in a reactor, which activate a generator to produce electricity and ultimately feed the electricity grid.
And the merger?
The use of nuclear fusion for energy production is a technology that humanity has not yet mastered. It consists of releasing huge amounts of energy by fusing the nuclei of atoms with each other, something that is done by accelerating atoms at high speed. This is similar to the reaction that occurs in stars such as the Sun.
Fusion is considered by many to be the ultimate solution for humanity’s future energy generation, as it does not generate radioactive waste, does not consume valuable resources, and can produce almost unlimited energy.
But successfully recreating it on Earth requires technology that is still under development.
In February, the European Commission (EC) classified nuclear energy as “green”, deeming it necessary for the transition from fossil fuel energy to energy without emissions of carbon dioxide (CO2), the main greenhouse gas.
Nuclear power plants emit an average of 28 tonnes of CO2 for each gigawatt-hour of energy produced, well below the 888 Tn/GWh for coal, 735 Tn/GWh for oil and 500 Tn/GWh for natural gas, according to the technical report. of EC.
Solar energy emits almost three times more CO2 than atomic energy, 85 Tn/GWh, while hydroelectric and wind power are the cleanest, with production of 26 Tn/GWh.
According to the same report, nuclear energy also consumes fewer mineral and fossil resources compared to other sources and generates very low amounts of chemical waste, sulfur dioxide and nitrogen dioxide — which can generate acid rain.
The UN, for its part, warned in 2021 that the global targets to contain global warming cannot be achieved if atomic energy is excluded. The organization claims that in the last half century, nuclear energy has reduced the equivalent of two years of global carbon dioxide emissions.
“Nuclear energy is as green and safe as renewable energy. It’s not a matter of opinion, but of comparing several peer-reviewed studies that go in the same direction,” says García.
But not everyone agrees that nuclear energy is clean.
“While nuclear power does not emit greenhouse gases at the same level as fossil fuels, it actually emits more CO2 per kWh than any of the renewables, as a nuclear reactor needs fuel to generate electricity and its production emits greenhouse gases. greenhouse effect”, assures, in turn, the representative of Greenpeace.
Bennasar cites data from the International Energy Agency (IEA) when he observes that, even tripling the world’s nuclear capacity, the reduction of carbon emissions would be only 6%, an impact he considers insufficient to meet the climate goals.
Critics of nuclear energy also claim that uranium extraction causes environmental damage and that dismantling a plant is expensive and polluting. They also say that there is a very low risk of an accident or military attack on nuclear facilities, but if that happens the consequences are potentially disastrous.
And the waste?
Another argument against atomic energy is that nuclear fission produces radioactive waste with a high polluting potential.
Waste is a by-product of nuclear power generation and consists of solid and liquid materials that contain radioactive isotopes.
They can be toxic for thousands of years and their treatment is very complex. For example, high-level radioactive waste must be stored in three different stages, the last one underground at a depth of between 200 and 1,000 meters.
“The nuclear industry has not been able to find a satisfactory and safe technical solution to this problem,” the Greenpeace representative told BBC Mundo.
Alfredo García, however, maintains that atomic energy “is the only one that is fully responsible for the cost of managing its waste, which is treated with the highest safety standards and for which there are scientifically agreed technological solutions”.
Is it profitable?
Building and maintaining a nuclear power plant is extremely expensive.
For example, the plant under construction at Hinkley Point C in the south of the UK, which will supply 7% of the country’s energy from 2025, will cost around US$30 billion, according to estimates.
Atucha 3, which will be Argentina’s fourth nuclear power plant, will cost US$ 8 billion (R$ 39.8 billion), according to the agreement signed in February between the country and China.
While a nuclear power plant typically exceeds $6 million per megawatt of capacity, a combined cycle gas power plant costs about $500,000 per megawatt of capacity.
However, producing nuclear power is much cheaper as it does not require a huge and continuous supply of fuel. Although enriched uranium is an expensive material, huge amounts of energy can be generated with small amounts.
Which countries are betting on nuclear energy?
With 96 reactors in operation producing more than 90 gigawatts, the United States accounts for nearly a third of global atomic energy production, followed by China and France, with more than 13% each, according to data from the International Atomic Energy Agency (IAEA). .
In France, nuclear power plants generate 70% of electricity production, making it number one in the world in this regard. French President Emmanuel Macron has announced an energy plan for the coming years that includes six new reactors with an estimated cost of around €50 million.
Germany had planned to close its last three nuclear plants this year, but the war in Ukraine has made that plan difficult. The president of the Ifo economic research institute, Clemens Fuest, recently declared that the plants must continue operating “at least until they overcome dependence on Russian gas, that is, several years”.
This difference in attitude shows Europe’s division over atomic energy: the governments of Germany, Austria, Denmark, Spain, Luxembourg and Portugal refuse to promote this energy source, while the self-styled “nuclear alliance” of Bulgaria, Croatia, Finland, France, Romania and Slovenia defend it. Recently the Czech Republic, Hungary, Poland and Slovakia have joined the latter group.
In Latin America, nuclear energy contributes only 2.2% of the region’s electricity production. There are seven reactors: three in Argentina, two in Mexico and two in Brazil.
In the world, the biggest bet on nuclear energy is China, which plans to become the next world superpower in this regard. Between 2016 and 2020, the country doubled its capacity to 47 GW, with 20 new plants, and by 2035 it should reach 180 GW, almost double the current capacity of the United States.