Before NOX Energy was quietly slashing electricity bills across Europe, it was just a scribbled list in a notebook and two co-founders who had barely met in person. Today, their smart platform runs invisibly behind major energy apps, turning heat pumps, EVs, and home batteries into money-saving powerhouses. CEO Axelle Moortgat shares how a string of failed ideas and a digital co-founder match sparked one of energy tech's most exciting startups.
Every entrepreneurial story has a physical cradle. What was NOX's "garage"?
"My childhood bedroom. I was still living with my parents, while my co-founder was studying in London at the time and worked from his student room there. We were fully remote from day one. I think we met in person two or three times, and the fourth time was straight away in New York.
But the idea itself, and the first leads with companies like Daikin, all came before New York. The business development and the idea were already there in broad strokes."
What does NOX Energy do, in a nutshell?
"We connect energy suppliers with the manufacturers of heat pumps, electric cars, solar panels and batteries, and we integrate into the app of either the manufacturer or the supplier. Someone with a heat pump simply opens their Daikin app or their Eneco app, enters their username and password, and connects. NOX sits behind that in the back end and steers the heat pump smartly to lower the electricity bill.
We can do every type of optimization: dynamic tariffs, aligning with the solar power you generate yourself, but also trading on the electricity markets. Basically anything that brings the end customer's bill down. The manufacturer or energy supplier pays us monthly per connected device, plus a platform fee. So it's a B2B software platform."
How did NOX come to be?
"I always knew I wanted to start a company. After graduating and four months of traveling, I suddenly had to return home due to a family loss. I found myself with a degree, no plan, and a notebook full of startup ideas I had written down during my trip.
I started testing them one by one. The first three failed. After four months of no income, my parents and friends were skeptical, asking if I shouldn't just get a real job. But once you start building something you're passionate about, it's hard to turn back. The fourth idea turned out to be NOX."
How did you find your co-founder?
"Through the Y Combinator co-founder matching platform, which is basically Tinder for co-founders. He's from Brussels, but was studying in London at the time. Honestly, I tried everything: Facebook groups, lots of events, a student organisation. You just have to try a few times, and something will come out of it. Whether it was the platform or pure coincidence, I can't say. It happened because I talked to so many people."
How important is it to have fellow entrepreneurs around you when starting to build?
"You need to hear the hard stories from fellow founders, not just the success stories. From the outside, everything looks polished, but people compare themselves to rare exceptions. I’ve spent hours driving around doing physical installations myself, with all my electricity knowledge coming from YouTube videos. It’s not as pretty as it looks.
Knowing that other founders go through the same grind gives you conviction. You keep going because you know that eventually, things will click and break through."
Today, you and your team have your own office in Antwerp. What does that bring you?
"With thirteen people, it's just great to have our own space. Conversations happen faster, and there are things you discuss inside the company that aren't meant for the outside world. There's more laughing, more inside jokes. That's good.
I'm very much an in-person person. Teams miss a lot of context when everything is remote, and you end up holding meetings constantly just to keep everyone up to date. At our place, everyone is at the office. You walk in: this meeting happened, this, this and this. Two minutes, and everyone's informed. You start discussing, you go for a drink in the evening, and a lot happens there too."
What is your biggest motivator?
"It's purely intrinsic. Having your life in your own hands, watching it grow and thinking: okay, this is really going well. Choosing your own colleagues, building the whole culture. There's a huge sense of togetherness. Everyone wants this to grow, and everyone has shares, so we're all in it with the same intentions. A deal comes in? We open the champagne. Life isn't a job anymore. It's one big project we're all working on together."
"This isn't just a job anymore. It's one big project we're all working on together."
Looking back two and a half years: are you where you hoped to be?
"I would have signed for where we are now without even reading the contract. Really, what the hell. I'm always in the mode of 'we have to keep going, it has to get better'. But when I look at what I wished for a year ago: boom, this is it."
And where do you see NOX in a few years?
"As Belgians, we often measure success by headcount: they already have thirteen people, fifty, a hundred. We don't agree with that at all. Our goal is to grow in revenue. We really want to become a unicorn, and to get there, maybe reach a hundred million euros. That's the target. But not necessarily by growing in people.
The team as it is now is perfect. Between thirteen and fifteen people you can keep everything flat. Everyone knows everything and there's a lot of context. I barely have to manage, because everyone is super smart and can make their own decisions. There's a lot of ownership. I think you lose that once you go over 25. So building a unicorn with 25 people, that's the dream. I don't know if it will work. If we need more people, we'll hire them, but out of necessity rather than desire."
Axelle Moortgat is co-founder and CEO of NOX Energy, which she started in 2024 with co-founders Louis Clermont (COO) and Martin Michaux (CTO). Today, a team of thirteen in Antwerp helps energy suppliers and manufacturers steer heat pumps, EVs, solar panels and batteries to lower their customers' energy bills.