The widespread blackouts in Spain and Portugal raise questions about the resilience and flexibility of their electricity grids. While various reasons for the blackouts have been discussed, in my view the most likely cause is that the blackout may have been caused by a lack of preparation for the sudden fluctuations in renewable energy that could have triggered the total blackout.
Of course, such situations are likely to recur in the future unless appropriate solutions are found here and now. What we have seen in Spain and Portugal can be seen as a good example of the importance of energy storage solutions, which can not only avoid energy waste, but also be the key to a more stable and reliable energy system.
How can a blackout happen?
First, let me explain what it means to say that not enough has been done to prepare for possible sudden and large fluctuations in renewable energy production. This is especially true given that, according to Spain’s national grid operator, Red Eléctrica de España, renewable energy sources (RES) will account for a record 56% of the country’s total electricity generation in 2024.
Imagine that one day, in a matter of seconds or even milliseconds, a certain number of renewable energy sources – solar or wind power plants – that are producing a significant amount of energy, suddenly shut down and do not produce as much electricity as they should. This would change the frequency of the electricity grid and increase the strain on the remaining sources, such as hydroelectricity, as the country’s electricity consumption would exceed its production.
Each power source has safeguards based on frequency to prevent it from being too high or too low, as well as voltage and other parameters. This creates a chain reaction. If the frequency is too high, the weakest remaining source of power is the first to be switched off. After it is switched off, the difference between consumption and generation increases even more, so the next source is switched off, and then the next, until there are no more sources.
It could also be the other way round – production starts to exceed consumption and the frequency increases. Every generating plant on the grid has its own limits, safety margins, within which it can operate. And when those limits are reached, the plant shuts down.
The importance of balancing and storage
However, when electricity production exceeds consumption – for example, due to intensive solar or wind generation – unpleasant situations associated with blackouts can be easily avoided by balancing electricity.
Electricity storage (battery systems) can be an excellent way of doing this. They store excess energy when production exceeds consumption, and release the stored energy back into the grid when consumption exceeds production or when disturbances occur. This flexibility allows the voltage and frequency of the grid to be kept within the right parameters, which is essential for its stability.
Energy storage devices are not new and are rapidly gaining popularity among domestic consumers. However, this does not necessarily mean that most electricity consumers should have one in their home in order to achieve the best possible energy balance in the country.
To avoid future blackouts like the current one, Spain and Portugal simply need to consider increasing the number of suppliers in the electricity balancing market. If the blackouts in Spain and Portugal are indeed caused by unbalanced electricity, it is even more encouraging to assume that there are not enough active balancing companies in these countries to be able to mitigate such temporary peaks and troughs.
Balancing companies are the entities that help the electricity grid maintain a balance between generation and consumption in real time. These companies use the sources I mentioned earlier, such as energy storage, to store excess energy or temporarily reduce consumption, and typically increase supply quickly when the grid needs it.
There is no doubt that if such balancing companies – using advanced control systems, software and energy storage – were more widespread, grids would be more flexible and less vulnerable to emergencies.
In short, energy balancers are a kind of “helping hand” to the national transmission system operator, helping to prevent imbalances that could lead to blackouts like those in Spain and Portugal.
Good software is also important
In considering the causes of the blackouts in Spain and Portugal, much thought has been given to the potential for cyber-attacks. Although this is less likely, the experience of the southern countries is a good example of how, in order to avoid blackouts, absolutely all countries need to pay more attention not only to electricity balancing, but also to more reliable software for solar and wind power plants or storage.
It’s no secret that a large number of devices are dominated by Chinese software, such as Huawei, Xiaomi and ZTE. So, in theory, China itself could easily wreak havoc. Its manufacturers know where their devices are because their software is also used for surveillance. So it would be easy for them to shut down devices in a particular area with the press of a few buttons, disrupting the power supply in a particular country.
And the use of reliable software would not only allow real-time monitoring and analysis of power generation and millisecond decisions (e.g. whether to shut down the system or switch on a backup supply), but also monitor attempts at cyber-attacks. Through automated mechanisms, it
could shut down specific sites, specific mechanisms and isolate a specific network to prevent the entire network from being attacked.
Trusted software could ensure that external actors cannot intercept or modify data between devices and control centres, and that only authorised users or systems make changes to operations.
The blackouts in southern Europe are a reminder that the energy system of the future needs to be smart as well as green. The solutions lie not only in new generation capacity, but also in the ability to manage that energy – to store it, to distribute it, to respond to changes in real time. So reliable software and smart are becoming a necessity, not a luxury. It’s not just blackout protection – it’s an investment in a more secure, stable and resilient energy future.
Dr Robert Janickas, Chief Technology Officer, Inion Software