Never could imagine that the words “wind energy” and “nicely balanced” would be used in the same sentence. This was achieved in this tweet (for the international readers, “BE” is the country code for Belgium):
BE update: Wind offshore dropped as of 10am, onshore as of 11am. And it is keeping the system nicely balanced. But of course, if only we could have dynamic demand response to this, society wouldn’t have to loose this cheap energy.
This are the graphs that accompanies the tweet:
There was indeed a sudden loss of wind capacity somewhat before noon, correlating with a negative price and leading to positive prices again. Initially, I assumed that the twitterer was being sarcastic, mocking a sudden wind lull, but scanning through his Twitter time line suggested that this might not be the case…
There was however a comment on the tweet that seemed to explain it:
Offshore wind reduces to keep system balanced, while nuclear delivers the bulk and remains on full power.
It is accompanied by this graph:
The graph confirmed the sudden loss of wind capacity somewhat before noon and showed that it lasted until around 3 pm. Also here, the suggestion seemed to be that wind “balanced” the system while nuclear kept producing at full power.
That was not the only weird thing. There was also a response from a politician of the Flemish Green party to this tweet that was puzzling (translated from Dutch):
Absurd. Wind energy is as always on the appointment. Instead of just producing, they switch off to give way to nuclear energy. Important lesson for the future: wind is the game changer, nuclear is the distorter.
Once again, wind was assumed to have balanced the system and even stepped aside to give way to nuclear energy.
Then I forgot about it for a while, until I found an open letter from the CEO of Eneco (an energy provider) addressed to the “leaders and energy experts of the country”. This made clear what actually happened (translated from Dutch, my emphasis):
There is plenty of wind these days and the sun is shining. Renewable energy could provide half of our consumption. In itself this is a good prospect: better air and cleaner electricity from wind & sun. We should all be pleased with that.
Now that everyone is busy overcoming this health crisis, we are actually experiencing a quiet energy crisis. Because nuclear power plants can’t simply be adjusted or shut down, an abundance of nuclear energy dominates our country. As a result, Eneco feels obliged to shut down a large part of its 104 windmills in order to avoid excess production.
Now it falls all in place. Nuclear power plants in Belgium generate electricity at a constant level and generally don’t react to frequency changes on the grid, unless in an emergency. This was obviously not the case on April 21. The open letter showed that this dip was not a sudden lull in wind speed, it was Eneco (and maybe other providers) shutting down some windmills in order to “avoid overproduction”.
The reactions to this event are however overblown. We seen such reactions many times before when some event was favorable to wind (and solar). When there is an exceptional amount of wind, then we hear (the experts in) the media cheering about the progress that wind made because of record electricity generation. Ignoring that these events only last for a short time (minutes or hours) and that the other 99.99% of the time electricity generation by wind was not as favorable.
A similar situation now. When some windmills were shut down, it is suddenly framed as “wind balancing the system”. For heavens sake, this only happened during 3 to 4 hours and only downwards. Did they found yet another way of glorifying wind power?
This brings us to the question: WHY did Eneco shut down 104 of its windmills? Although there was an overproduction at that point, it was not an emergency, so whether or not wind would have powered down production, it would not made much of a difference. At least not when it comes to the grid.
However, shutting down some of its production could make a difference for the provider itself. I think the real reason is not mentioned in the open letter. It was all over the media lately and it was also hinted at in the graphs that were showed in the tweets above: negative prices. On the one hand, it was sunny and also quite windy in the last few months, so this means that a lot of electricity was produced by solar and wind. On the other hand, there was not much demand because of the COVID-19 measures and the holidays. This means that the spot prices were low and even went negative on several occasions. Although wind electricity producers are protected against such negative prices, this support is not unlimited and they didn’t earn much money either, notwithstanding it was windy at the time.
That is of course not how the CEO sees it (translated from Dutch):
It is like a ban on organic vegetables from your local grower as the unsustainable mass producers continue to flood the market. And that kills all our sustainable ambitions.
That is not exactly a good analogy for what happened. Nobody “banned” wind power, the company itself made the decision to shut down 104 of its windmills. It is more like that local grower deciding not to sell his produce because he doesn’t get a premium for it, blaming the other growers that they produce too much and therefor driving prices down…
Nuclear has a different strategy than wind in that regard. Nuclear produces at the same level and this will be favorable in some cases (when demand is high and supply is low) and less favorable in other cases (when demand is low and supply is high). They will accept the lower or even negative prices, as long as the final balance is positive.
But then, doesn’t this event show that wind is actually more flexible than nuclear? It obviously can power down on a dime when it is necessary. Just looking at the aspect of powering down, it is certainly true that this is much easier for wind than for nuclear. I surely like the idea that wind producers would take more responsibility for balancing their intermittent production themselves (even if it is currently only curtailing).
That is however not the issue raised in this open letter. Remember, the CEO doesn’t really want wind to balance the system. In this open letter, the CEO points his finger at nuclear, saying it is too inflexible and therefor not allowing them to earn money when the situation is favorable for wind. That doesn’t just show the inflexibility of nuclear (because it doesn’t give way), but also the inflexibility of wind (because it is dependent on a force that is not related to demand).
For some reason, the words “pot” and “kettle” come to mind…