Is it time to say yes to nuclear energy?

The first Spanish nuclear power plant came into operation in 1968. In 1983, the Government of Felipe González applied a nuclear moratorium that paralyzed the entry into service of five of the planned reactors. After a fire at Vandellós I in 1989, it was decided to leave this reactor inoperative, despite there being no personal damage to the plant or contamination from the outside.

With the decommissioning of the José Cabrera plant (Zorita) and the definitive cessation decreed in 2017 for Santa María de Garoña, the installed power of the seven operating reactors is currently 7,124 MW. The Government and the owners of the plants have agreed on a staggered closure that will culminate in 2035.

According to the above, nuclear energy arouses mistrust in Spain. However, the European Joint Research Center has concluded that “there is no science-based evidence that nuclear energy causes more harm to humans or the environment than other electricity production technologies already included in the European taxonomy as activities that contribute to climate change mitigation. This enables the inclusion of nuclear energy in a catalog so that it can benefit from preferential financing as it is recognized that it is an effective measure to combat climate change that does not present more risks than other technologies already included.

An expensive technology?

Sometimes it is suggested that the consumption of water for cooling makes nuclear technology unfeasible in Spain. Certainly, a nuclear needs to dissipate heat, like any thermal power plant.

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However, it is not difficult to demonstrate that a typical 1,000 MW plant requires less than 7.5% of the flow of the Manzanares River (a tributary of the Jarama, which in turn is a tributary of the Tagus) for its cooling.

Regarding the economy, critics point to two aspects. On the one hand, that the new generation III plants have high costs due to the huge investments in safety. Thus, the international consultant Lazard places the cost between $131 and $204/MWh (between €119 and €186/MWh), while the French electricity company EDF estimates it between €60 and €70/MWh, according to the International Energy Agency .

As I explained at the time, these imbalances are due to the fact that Lazard has taken only 70% of the hours of the year for the annual hours of operation (in Spain in 2020 it was 85%) and, in addition, it has made the calculation for 40 years of life instead of 60, as would correspond to a new plant.

On the other hand, the economic viability of purchasing the fuel is also criticized, despite the fact that it represents only 9.4% of the total cost.

Fuel reserves and waste management

Regarding security of supply, the identified uranium reserves are highly diversified: 89% is distributed among 14 countries, with the remaining 11% being distributed among even more. As recharges are made every one or two years, the purchase can be scheduled avoiding conjunctures. It is also possible to concentrate the purchase for several refills, given the reduced volume of fuel.

Global distribution of uranium reserves. /

NEA

Related to the fuel, is its management once used (the so-called radioactive waste). Said fuel can be managed in an open cycle (all spent fuel is considered waste) or closed (it is reprocessed to recycle fuel).

The closed cycle is today more expensive than the open cycle, although it allows the volume of waste to be stored to be reduced by more than 80%.

It is important to understand that the generation cost of the plants fully internalizes waste management (€13.1/MWh in Spain). In addition, said waste is highly concentrated, with 10,000 m³ for the Spanish plants, which amounts to a height of less than 1.5 meters above a football field.

That small volume facilitates waste management. During the useful life of the plant, they are stored in it in the fuel pool to cool down. Later, they can be temporarily taken to a warehouse in the own installation (ATI) or centralized (ATC). There they can remain up to 100 years in standardized containers outdoors or in a conventional warehouse.

Finally, the waste will be sent to final storage, known as deep geological storage (AGP) like the one being built in Finland and planned in other countries.

In the AGP, the waste loses radioactivity until it reaches the levels existing in nature, a process that lasts about 25,000 years. These definitive storage facilities are designed in stable geological formations hundreds of meters deep so that they can remain safe for hundreds of thousands of years, with passive safety measures and without human intervention.

Plant safety

Regarding the safety in the operation of power plants, there have been three major accidents throughout history: Three Mile Island (1979), Chernobyl (1986) and Fukushima (2011).

In the first one there were problems in the cooling and some errors were detected in the protocols that were later corrected. As for Chernobyl, it was produced in an RBMK reactor, a design far removed from Western light water reactors. This caused the system to become unstable during a test intended to improve security.

Finally, in Fukushima the accident was caused by a natural catastrophe due to the lack of foresight in leaving the emergency generator sets responsible for ensuring the cooling of the plant in an area with conventional protection. Despite this, the emissions were one tenth that of Chernobyl and there were no effects on the public or exposed professionals.

Conclusions

If we add to the above arguments that, according to a recent UN report, nuclear energy is one of the generation technologies with the lowest CO2 emissions throughout its life cycle, we can only conclude that in order to meet our commitments climatic conditions, the useful life of nuclear power plants should be extended, under the strict supervision of the regulatory body, also taking advantage of current sites to build small modular reactors (SMR) with execution times of less than five years and greater efficiency of the fuel cycle if They are generation IV.

The energy problem cannot be solved with a single measure. Nuclear energy must be part of the catalog of solutions as it is safe, produces controlled, identified and manageable waste and is economically viable.

This article has been published in ‘
The Conversation’