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Energy Flexibility

What if there is no sun or wind? And what is dunkelflaute?

Curious how FlexiO manages your home battery and EV during a dunkelflaute when there's no sun or wind? Discover our smart, hands-off approach.
November 4, 2026

A grey day without sun or wind. Solar panels and wind turbines generate almost nothing. As a result, expensive gas-fired power plants have to step in to keep the lights on. It makes you wonder: What does FlexiO do in that case?

Days like this even have a name: a dunkelflaute. Little sun, little wind, and therefore scarce cheap or green power on the market. It affects the whole of Belgium a few times a year, which means it affects you too.

What FlexiO does

Nothing spectacular, and that is precisely the point. Your battery and EV are not forced to do anything you don't want them to do. FlexiO simply takes an honest look at what can be gained that day and optimises accordingly.

If there isn't much to optimize, FlexiO does very little. Your EV charges when it impacts the grid the least, even if that specific moment is less cheap than usual. Nothing is forced, and your comfort at home remains completely untouched.

As soon as the sun or wind returns, FlexiO gets right back to work for you. Offering a fair reward for your contribution, just like always.

Why that is okay

A dunkelflaute is not an issue with your installation; it is a period where the entire country simply has less energy to go around. FlexiO cannot change that fact, and therefore makes no empty promises on such days.

We always evaluate what an action costs (taking into account battery degradation, taxes, energy losses, etc.). If the benefit of an action is lower than its cost, FlexiO holds off.

It waits until an action actually yields a net profit or saves you money. We always steer things to your benefit, even if that sometimes means pausing.

In a nutshell

No sun, no wind? Just keep your home cozy. FlexiO will handle the rest as soon as there is an opportunity to optimize again. You don’t have to lift a finger, even on days when the weather doesn't cooperate.

Curious about what FlexiO can earn for you? Calculate your return!

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