For years, Tom Bosseler and Pierre Pirotte had no shortage of startup ideas. Most never made it beyond conversations between two childhood friends studying together in Munich. Eventually, they realised they had spent enough time imagining what it would be like to build a company. It was time to start one.
“We asked ourselves: ‘If not now, when?’ It’s fun to dream and have all those ideas, but we finally wanted to create something,” recalls Bosseler.
The idea that became WattSwap did not come from one of those brainstorming sessions. It came from a problem much closer to home.
From classmates to co-founders
Bosseler’s father was trying to create an energy community with his neighbours so they could share locally produced electricity. Although the concept already existed, putting one in place meant navigating a surprisingly complex administrative process involving multiple stakeholders and considerable paperwork.
“The pain point came from my dad,” says Bosseler. He told them that “if there was a service that could take care of everything, he was sure many other people would use it too.”
The conversation prompted the two friends to explore a sector they knew little about. What they discovered surprised them. Energy communities already existed, the European regulatory framework was already in place and Luxembourg had begun embracing the concept. What was missing, they believed, was a simple way for ordinary people to participate. Rather than reinventing energy communities, they saw an opportunity to remove the administrative barriers preventing more households, businesses and municipalities from joining them.
Bosseler and Pirotte had known each other since primary school and later studied together in Munich, where entrepreneurship became a recurring topic of conversation. Startup ideas came and went, but few survived beyond the initial discussion. Looking back, Bosseler laughs at those early attempts. “They were very bad, actually,” he says. Even so, the ambition remained the same: one day, they wanted to build something together.
Making energy sharing simple
What we found out was actually the friction to start was way too high. People just want to register like any big digital platform today, and we do the rest.
Today, WattSwap provides a platform that makes energy sharing accessible to a much wider audience. It enables households, businesses and municipalities to join or create energy communities, matching electricity producers with consumers while handling registration, billing and the administrative processes behind the scenes. The goal is to make sharing locally produced renewable electricity as simple as signing up to any other digital service.
For the founders, simplicity was just as important as the technology itself.
“We found that the friction to get started was simply too high,” says Pirotte. “People just want to register like they would on any digital platform today. We do the rest.”
That same philosophy shaped the company’s business model. Instead of charging users a subscription fee, WattSwap earns a percentage of the savings generated through energy sharing, meaning the company only benefits when its users do.
This is a win-win for everyone and we just benefit with you from the win.
The seasonal nature of solar energy also means the company is already looking beyond rooftop panels. To ensure energy sharing remains attractive during the winter months, the founders are beginning to integrate wind energy into the platform. “We’re looking also into wind energy, for example. We already have one wind turbine in the mix where people can get cheap electricity already at night or in winter,” says Pirotte, adding that the long-term objective is to offer a more balanced mix of renewable energy sources throughout the year.
Alongside the consumer platform, the founders have also developed a white-label software solution that allows municipalities, cooperatives and other organisations to manage their own energy communities using WattSwap’s infrastructure under their own branding.
Growing through word of mouth
Although WattSwap was incorporated in April 2025, much of its first year was spent validating the concept through pilot projects before opening the platform to the wider public in early 2026. The founders initially hoped to reach around 1,000 users by the end of the year. Instead, they surpassed that objective several months early, with the platform now counting around 1,500 users.
“We didn’t even anticipate that the demand would be that high and positive,” says Bosseler.
Rather than relying heavily on advertising, much of that growth has come through recommendations. Existing producers naturally encourage neighbours, friends and local businesses to join because larger communities create greater value for everyone involved.
“If we were not solving anything meaningful, the market would not come after it,” says Pirotte. “We see we’re solving a problem for people.”
Building a company after work
Growing the business has not been without its challenges. Both founders have full-time jobs and develop WattSwap during evenings, weekends and every available moment outside work.
That entire juggling – not only with work, but also with your personal life and social life – is something we had to learn.
As adoption accelerated, they also encountered challenges beyond their own control. Activating energy communities still depends on administrative procedures involving Luxembourg’s electricity grid operator, meaning rapid growth exposed bottlenecks elsewhere in the ecosystem.
Entrepreneurship has also required patience.
“You show up every day because you have to and because you want to,” says Bosseler. “The reward doesn’t come today. We might be working on something now where we won’t see the results for the next few months, but that’s okay.”
Building the company alongside full-time jobs has also taught them to be disciplined, making the most of evenings and weekends while continuing to grow the business step by step.
Twenty years of trust
I know he’s giving 100%, and he knows I’m giving 100%.
Having known each other for around twenty years, the founders say trust has become one of WattSwap’s greatest strengths. Responsibilities are divided according to their respective skills, disagreements are discussed openly and both know the other is equally committed to the project.
“We can blindly trust each other,” says Bosseler. “I know he’s giving 100%, and he knows I’m giving 100%.”
That trust, they believe, explains why building a company together has strengthened rather than tested their friendship. As energy communities continue to expand across Europe, the founders see opportunities to bring WattSwap to new markets while continuing to develop products that support the energy transition.
After years spent discussing startup ideas, the two childhood friends have finally found the one they were looking for. Their challenge now is no longer finding the right idea, but continuing to build a company around it.
