This week marks 40 years since Chernobyl. Nuclear power plants are the great challenge, social, economic and energy-related, of the coming decades. It is an issue without political consensus, with social repercussions and a large economic impact. Now, additionally, also geopolitical.In the EU, electricity generation is distributed approximately as follows: 44% renewables (wind, solar, and hydro), 23% nuclear, and 33% fossil, mainly gas (20%) and coal (10-13%).Spain presents a slightly different profile: renewables exceed 50%, nuclear is around 20% and gas also hovers around 20%, while coal is already residual.More than half of European electricity is linked to inputs from outside the EU, as gas and coal are, for the most part, imported. The other 50% corresponds to energy generated with own resources: renewables and nuclear. Renewable energy is variable and nuclear provides continuous generation.If the objective is to eliminate fossil generation in order not to depend on other regions, we need an energy source to cover the third of the European electricity system that fossils provide. Replacing this 30-33% solely with renewables would require massive oversizing accompanied by large-scale storage, still costly and insufficient.As of now, the only alternative is to expand the nuclear base. In approximate terms, the European Union currently has around 100 operational reactors. To completely replace gas and coal, it would be necessary to add on the order of 120 to 150 new standard-sized reactors to the European total. This is more than doubling the current capacity and would require two or three decades, with a distribution among the main countries.The argument of safety is often invoked as a brake. However, the evidence shows a system with very high standards. Since Fukushima in 2011, there have been no serious accidents in the developed world, and in Western Europe the nuclear park has been operating for decades without incidents of systemic impact.It makes little sense to invoke fear of an accident. Europe already coexists with nuclear energy. Expanding it does not introduce any new category of risk. The risk already exists.Nuclear offers a stable, predictable, and emission-free base. It allows the system to be sustained when there is no sun or wind and reduces dependence on unfriendly countries. For industry, it means more stable prices. For the economy as a whole, less vulnerability.Forty years after Chernobyl, Europe faces a difficult decision. But there is no alternative.

February 14, 2025. A Russian drone loaded with explosives crashes against the structure protecting the old sarcophagus of the Chernobyl nuclear power plant. The fire burns for three weeks, damaging the walls of the new construction and forcing its repair as it is no longer capable of containing radiation. However, a year later, on the eve of the fortieth anniversary of the worst atomic disaster in history, maintenance is stalled. Russian attacks on Ukraine are hindering the work of engineers, and environmental organizations like Greenpeace have just warned that, if nothing is done, there is a risk that the sarcophagus will "collapse" and cause a "catastrophic" radioactive leak, which "knows no borders."