Your electric grid has several weak points

The Spanish Government and Electricity of Spain, the operator responsible for ensuring that the Spanish electrical system is efficient and safe, have not yet announced What has caused the total electric blackout that We have suffered in Spain and Portugal For many hours. We may never get to know with absolute certainty What has triggered this collapsebut what we know is how Spanish electrical infrastructure works and what are its weak points.

To identify its vulnerabilities it is crucial that we know with some precision what the structure of the network is, the role of the strategic interconnection points (they are known as nodes of the network) and how electricity is transported from the facilities in which it is generated to the places where it is consumed. An interesting note before getting into flour: in 2024 23.2% of Electricity of the Spanish Energy Mix It had a wind origin; 20%, nuclear; 17%, photovoltaic solar; 13.6%, combined cycle; 13.3%, hydraulic; and the rest proceeded from the burning of coal or other renewable sources.

The electricity grid has a complex structure with several critical points

To understand how electrical energy is generated and how the infrastructure that is responsible for transporting it to our homes and companies works, we need to investigate the structure of the network. The first link in the chain, as we can intuit, are the centers for the generation of electricity. As we have just seen, the Spanish energy mix is ​​mainly held on wind farms, nuclear centralsphotovoltaic solar facilities, combined cycle plants and hydraulic plants.

Once it has been generated in the production centers, electricity is distributed throughout the Spanish territory through A high voltage network which has 44,000 km of 220 kV and 400 kV lines. However, close to both the facilities in which electricity is generated and the places where it is consumed Electrical substations are found. These nodes of the network are responsible for transforming the voltage with the purpose that electricity can be transported with the minimal possible energy loss. This is the reason why the substations that are close to generation plants raise high voltage energy (from 200 to 400 kV).

Once electricity is close to the points where intermediate substations will be consumed are responsible for reducing the voltage to 132 kV. Red Eléctrica de España is responsible for the administration of high voltage infrastructure, while medium and low voltage networks (15 to 30 kV) are managed by Endesa, Naturgy, Iberdrola and other energy companies. We already have a quite accurate idea about how the electricity grid is carrying electricity to our homes, but we have overlooked very important nodes: the electrical control centers.

These facilities are part of the infrastructure administered by Red Eléctrica de España. They are responsible for supervising in real time the operation of the entire network to identify anomalies and prevent possible malfunction. These nodes are precisely those that are in all likelihood have a leading role in the resolution of the total blackout that we have suffered just a few hours ago. However, we still need to investigate more links more than one infrastructure that, as we are checking, is complex.

On the one hand, the Spanish electricity grid is connected to the electrical infrastructure of three countries: France, through four connections with a capacity of 2,800 MW; Portugal, with several links that add up to 3,300 MW; And finally, Morocco, through a single underwater cable of 700 MW. The cooperation of France and Morocco has been crucial when restarting the Spanish electrical infrastructure. To conclude, we cannot ignore the last link in the chain: the urban transformers that we can all see in our locations and neighborhoods. They are responsible for reducing the voltage to a level that can be used by the appliances and the devices we have at home (230 volts).

These are the weak points of the Spanish Electric Red

We already know with some precision what the structure of the electricity network is and what role each of its nodes has, so we can understand effortlessly what makes it vulnerable. One of its most obvious weak points is The regional imbalance which occurs between excess generation in southern Spain and the high demand of the center and the northern peninsular. The facilities of Andalusia and Extremadura produce a lot of electricity, but the greatest demand does not come from these autonomous communities; It resides in Madrid, Catalonia and other communities of the North Spanish. This imbalance submits the network to an effort that requires the implementation of reinforcements that are not always available.

In addition, the average and low voltage network is touching saturation in many areas. This simply means that the demand for electricity at some points is greater than the service capacity that is available in those areas. This causes that there are currently several thousand generation megawatts that have been requested and They cannot be delivered Because the network has reached its maximum electricity transport capacity. If we also take into account that some parts of the transport network are old and have supported for many years a great effort it is reasonable to conclude that it is necessary to reinforce them and carry out effective maintenance.

Whatever this is not all. Renewable sources have more and more weight In the energy mix, while fossil origin does not stop losing relevance. There is no doubt that it is good news on the way to An energy model free of pollutant emissions in which we have embarked, but poses a challenge: the control centers that we have spoken some lines above must be able to sustain the stability of frequency and tension. It is possible, in fact, that this is the origin of the collapse that we have lived a few hours ago, although for the moment it is only a conjecture.

A last critical point that we should not overlook are cyber attacks that Spanish critical infrastructures and other countries are very frequently. Electric Red of Spain has ruled out that the blackout a few hours ago has been caused by a cyber attackbut on other occasions this organization and other Spanish critical facilities have recognized have suffered computer attacks that pursued to deactivate their capacity for service provision. At the current geopolitical tension and conflicting interests between the great powers, it is evident that both Spain and most countries with strategic facilities must invest in effective protection systems against cyber attacks.

Image | Kindel Media

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