Spain paid a blackout for green energy

The blackout in Spain on April 28 plunged the country into darkness and, as the Spanish media wrote, threw the country back into the XIX century. One of the main reasons could be green energy, which could not work, as traditional power plants do, at a crisis moment.

On the afternoon of April 28, millions of Spaniards faced problems they didn't even know they had. The blackout stopped trains, planes and even buses. The extinguished traffic lights provoked chaos on the roads, and the lack of electricity in stores led to the fact that bank cards were not accepted and supermarkets were closed. Mobile communications disappeared, and hospitals served only patients in critical condition. 30 thousand police officers were brought into the capital of the country to ensure order. Spain could not even imagine such a thing.

It is assumed that the first cause was temperature fluctuations in Spain and a fire in southwestern France, which led to fluctuations in power and frequency. So, the fire damaged the high-voltage line between Perpignan and Narbonne, which connects Spain and France. At the same time, at 12.15−12.30, the capacity of electricity exports from Spain to France was more than 1 GW, according to ENTSO-E. And the interruption of supplies led to a sharp oversupply of electricity and an overload of the power grid in Spain.

The triggered emergency automation at the same time isolated the Spanish power grid, but could not prevent a cascading shutdown.

At 12.30 pm, the power of power plants available to the network fell by 15 GW in 5 seconds (60% of total consumption). The French operator RTE recorded the automatic shutdown of the Iberian Peninsula from the pan-European power grid at 12.38.

At the same time, Spain's green energy could only aggravate the situation, which led to a blackout. According to Red Electrica, the capacity of solar power plants at 12.25−12.30 was 17.8 GW — 55% of the total generation in the country. Another 11% accounted for wind farms (2.1 GW).

The Daily Mail and The Telegraph note that the problem with solar and wind power plants is that, unlike coal and gas generation, they do not provide synchronous inertia that stabilizes the frequency in the network. And this made the Spanish power grid extremely vulnerable to sudden fluctuations caused by temperature fluctuations and disconnection of the interconnector with France. Red Eléctrica confirmed a sharp drop in frequency.

When the frequency in the network dropped due to problems on the interconnection, solar power plants could not compensate for the imbalance. Their operation depends on inverters, which automatically turn off when the frequency deviates from the norm, aggravating the collapse.

As a result, the capacity of power plants at 12.40 fell almost threefold — to 6 GW. At the same time, the capacity of coal and gas power plants did not exceed 2.5 GW at 12.30, and at 12.40 it dropped to 1.1 GW.

Theoretically, batteries could absorb excess electricity, but there are not enough such storage facilities in Spain. Nor did the interconnector in Morocco play its role.

It is significant that during the restoration of the power of the Spanish power grid after the blackout on April 29, gas generation has already become the main source of electricity for the country. According to ENTSO-E, at 8.00 (9.00 Moscow time), the capacity of gas-fired power plants reached 12.5 GW. The share of gas generation in total electricity production in Spain was 48%, while solar accounted for slightly more than 5% (1.4 GW).

"The electrical system obeys the laws of physics. This obvious fact was not always taken into account when politicians took measures affecting the country's electricity generation and transport networks. In Spain, for example, over the past decade there has been a revolution in the production of electricity, which has led to the fact that renewable technologies (primarily photovoltaic and wind) now occupy a large part of the energy balance," writes former president of Red Electrica Jordi Sevilla in El Pais.

He notes that there is a technical problem: solar and wind energy are not synchronous energy sources, while transmission and distribution networks are designed to operate only with minimal voltage in the energy they transmit. Therefore, a sudden jump in the production of renewable generation can lead to sharp voltage fluctuations in the network, which will lead to a loss of generation and, as a result, to power outages.

"Our energy system needs investments to adapt to the technical realities of the new generation, which, in turn, should also continue to improve its own technologies and storage systems. This is a requirement of the sector (and the system operator), to which the government does not listen. The PNIEC project was developed in the office with excessive messianism regarding renewable energy sources and without taking into account the technical problems associated with such a significant change in the Spanish energy balance and its compliance with the energy system," concluded the ex—head of the Spanish energy system operator.