When nuclear power plants force wind turbines to shut down

Wind power generation has broken records in Belgium recently. Yet entire parks have had to be shut down due to a glut of electricity. Blame it on nuclear power and the non-modularity of power plants? Not just … Analysis.

No one will have missed it, the wind is blowing, and strong, on Belgian territory in recent days. A nightmare for lovers of badminton in the open air but above all a boon for units producing electricity from wind, wind turbines. This Thursday, a record was even broken, Elia, the operator of the electricity transmission network, recording a peak of 4,038 MW of wind power in the electricity system, the equivalent of four nuclear reactors.

But there is a catch. Because the seven nuclear reactors continued to operate at full capacity during this time, the country found itself in a situation of surplus energy, pushing the price of electricity below zero. Consequence: the wind turbines of the Seamade offshore wind farm had to be stopped in their tracks, to the chagrin of their owner, Eneco. “We find it very unfortunate to have to cut wind turbines instead of nuclear reactors. Renewable energies should be a priority”, regrets Mark Van Hamme, spokesperson for Eneco Belgium.

“Stop the wind turbines while the wind blows, it’s the world upside down.”

Tinne Van der Straeten

Federal Minister of Energy

At first glance, the finding is sad. Indeed, depriving oneself of renewable energy in the era of energy transition seems somewhat gruesome. “Stop the wind turbines while the wind blows, it’s the world upside down”, has also reacted the Federal Minister of Energy Tinne Van der Straeten (Groen). But not everything is so simple and, in this case, other significant factors led Eneco to the decision to shut down its wind turbines. Explanations.

Storm and computer bug

The wind blowing, for wind turbines, is good. When it blows too much, on the other hand, it is imperative to pause them. It’s a matter of security. If this is not precisely this phenomenon that motivated the decision to shut down Seamade Park this Thursday, Winds that are too strong sometimes force operators to stop their wind turbines. This was particularly the case on Thursday morning, when the storm was in full swing.

“If there is a surplus of electricity in Belgium due to climatic conditions favorable to renewables, there is a chance that this will be the case with our neighbors.”

Pierre Henneaux

Professor specializing in electrical networks at ULB

Beyond this technical problem, another, much more worrying, largely explains the quack of this week. Indeed, while the electricity system had a surplus of energy, it was not possible to export this surplus to neighboring countries. “It should first be noted that if there is a surplus of electricity in Belgium due to climatic conditions favorable to renewables, there is a chance that this will be the case with our neighbors”, points out Pierre Henneaux, professor specialized in electrical networks at ULB. “Exports can take place when the capacity of the electricity system exceeds the load, but in order to be able to export electricity, neighboring countries must also want it,” he adds.

But here, beyond a similar situation in neighboring countries, a computer bug has added its two cents. “There was a problem with the platform allowing to anticipate purchases on the day-ahead market (short-term market). In this way, the default data was used and exports were somewhat limited.“, explains a well-informed source. Without bug, therefore, it would have been possible to export more, especially since Belgian prices, negative at that time, would no doubt have interested the neighboring countries connected to the network.

“It is reductive to blame it all on nuclear power plants.”

Anne-Sophie Hugé

Engie Belgium spokesperson

This technical concern will consequently have prevented Engie, the operator of the nuclear power plants, from foreseeing this restriction of exports. “It is reductive to blame everything on nuclear power plants. We could not foresee a bug at the level of the interconnections and nothing indicated to us that we would have to modulate our units“, commented Anne-Sophie Hugé, spokesperson for the energy company.

After 2025

In less than five years, the country’s seven reactors will be permanently shut down. And initially, while waiting for the full development of renewable energy, it will be gas-fired power stations that will complete the production mix. In addition, the country should be able to rely more on electricity imports, and therefore, on interconnections with its neighboring countries. Gold, in view of the events of this Thursday, it appears that the system is not yet optimal.

“The CRM will encourage gas-fired power plants and these are inherently more flexible than nuclear reactors.”

“The CRM (the mechanism of remuneration of the capacity which aims to guarantee the security of supply of electricity out of nuclear, Editor’s note) will encourage gas-fired power stations and these are, by nature, more flexible than nuclear reactors” , indicates here Pierre Henneaux. “However, situations of overabundance of the electricity supply are likely to recur in the event of favorable climatic conditions for renewables and to avoid having to shut down wind turbines, it will be necessary to develop storage, digitization of networks, improve and strengthen interconnections and make electricity demand as flexible as possible. Ultimately, it will also be necessary to make the systems more reliable and find emergency solutions in each country, ”he explains.

In summary, in the future and with the CRM, nothing will change as to the priority of the units in the market. The risk of having to stop them in windy periods will nevertheless be reduced by the greater modularity of gas power plants vis-à-vis nuclear power.. But, in addition to having a more responsive and controllable system, it will be a question of strengthening the interconnections and ensuring their optimal use. At the risk of endangering security of supply.

The Chamber approves the bis law on the CRM

The Chamber approved, on Friday in plenary session, the bill of the Minister of Energy Tinne Van der Straeten which adapts the capacity remuneration mechanism (CRM) approved under the previous legislature. In particular, it takes into account a resolution passed this summer by a large majority.

This modification was necessary to provide the legal basis for the royal decrees which should make it possible to prepare the first auctions, scheduled for next October. By then, the European Commission will, in principle, have pronounced on the compatibility of the CRM with state aid rules.

The next stage consists of the drafting of royal decrees relating, in particular, to the volumes required within the framework of the CRM. It is only when the volumes are fixed that the cost of the mechanism – for the moment estimated between 238 and 253 million euros – can be revealed..

Leave a Reply

Your email address will not be published. Required fields are marked *