Around noon on Whit Monday, a record amount of electricity was generated by wind and sun, enough to cover just about all of Belgium’s electricity consumption for a while. This is according to preliminary figures from high-voltage manager Elia.

This is the first time that solar and wind have been enough to cover just about all of Belgium’s electricity demand.

8 303 megawatts

Specifically, 8 303 megawatts of electricity was generated by renewable energy on Monday between 1 and 1:30 pm, an absolute record. Also Sunday, 7 695 megawatts were produced during the peak. The previous record dates to 2022 (7 122 megawatts). This covered virtually 100% of the demand for power on a weekend or holiday (8 gigawatts) at the peak. That never happened before, the high-voltage operator confirms.

“The world upside down”

For energy minister Tinne Van der Straeten (Groen), it is proof that the energy transition is coming up to cruising speed. “This weekend, we got a glimpse of our green energy future”, Van der Straeten said to the Belga press agency. “The more wind and solar, the lower the prices. But that also requires more flexibility from the system.”

Due to high production and low consumption, there was even a surplus of electricity this weekend. Resulting in historically negative imbalance prices of -658 euros per megawatt hour. To rebalance the power market, large consumers such as chemical plants are then paid to start consuming power, which is still an unacceptable aberration. Windmills were also to be shut down.

“Shutting down windmills, which produce cheap electricity, when the wind blows, that’s the world upside down”, Van der Straeten said about that. The construction of battery farms should therefore provide the necessary flexibility and accommodate all excess production.

Indeed, at present, transmission system operator Elia’s task is to keep the grid always balanced so that supply and demand are equal. This is necessary to keep the grid at a frequency of 50 Hz. A small deviation of a few millihertz is already enough to affect sensitive devices connected to the grid negatively.

The capacity of large battery farms in Belgium is said to hover around 150 megawatts currently and, according to Elia, there are about 1 800 megawatts of battery projects in the pipeline.

Minus € 90 per megawatt hour

Not only the imbalance prices – the prices to balance the grid – were negative. Electricity was also extremely cheap on the wholesale market this weekend, with prices as low as -90 euros per megawatt hour at some hours. Even ordinary consumers with dynamic contracts then receive compensation for their electricity purchases.

Smart grid

For high-voltage operator Elia, the shutdown of the wind turbines shows the importance of getting as many consumers as possible to participate in the market by using their flexibility – in the form of a heat pump or an electric car, for example.

“Such a consumer-oriented market model should ensure that everyone can benefit from such low or even negative prices. That way, people are financially rewarded when they consume electricity at times when there is a lot of renewable energy and also help to keep the grid in balance”.