Power electronics sits at every junction in the energy system

“To explain what power electronics is, I usually start with something familiar,” says Wilmar. “Think of your laptop charger or phone charger. Tools we use every day. What these chargers do is convert electricity from the socket into what your device can use. That is essentially what we focus on within the power electronics research line: develop ways of converting energy as efficiently as possible.”

That conversion may seem obvious, but it is anything but simple. Conventional chargers are often bulky, and they warm up quickly. “That heat is really lost energy,” Wilmar says. “You are paying for electricity that never reaches your device. Our challenge is to continually improve this and to convert energy with technology that is smaller, more efficient, more reliable and, of course, more sustainable.”

A key technology in the background

“Without power electronics, many technologies simply would not work,” says Wilmar. “Take a solar panel: it produces direct current, while the electricity grid runs on alternating current. Without an inverter, a power electronics device, you cannot use that energy or feed it into the grid.”

The same is true for electric vehicles. There, power electronics does more than convert energy between the battery and the motor. It also controls how the whole system behaves, from how fast the vehicle drives to how much power goes to the wheels, and how energy is recovered during braking.

“In fact, power electronics sits at every junction in the energy system: between generation and the grid, between the grid and the user, and between storage and use. It is the technology that connects and controls all those different forms of energy.”

And its importance has only grown over time. Where the energy system used to be relatively straightforward, it has now become far more complex, Wilmar explains: “In the past, electricity was generated in large power plants, often close to users and based on coal, gas or hydropower. These were essentially mechanical systems producing electricity and sending it directly to the consumer. Everything was built around one type of current and one direction of energy flow, over relatively  short distances.”

Today, the situation is very different. “We have moved to a system with solar panels, batteries, electric vehicles, and decentralised energy generation,” he says. “That means much more energy conversion is needed, and therefore much better power electronics.”

Smaller, more efficient, more sustainable

For Wilmar, the direction is clear. “If we want the energy transition to succeed, we need to keep improving efficiency and scalability,” he says. “Power electronics will only become more important.”

At EnergyVille, the focus is on improving that technology to achieve higher efficiency, smaller systems, longer lifetime, and lower climate impact. “In 2025, we made important progress,” says Wilmar. “We succeeded in making converters more compact, reducing losses and increasing reliability.”

According to him, EnergyVille itself is an important catalyst for that progress. “The big advantage is that all the expertise is brought together in one place,” he says. “I sit next to people working on batteries, solar panels, or energy systems. That close proximity helps ideas move much faster.”

Such collaboration also translates into concrete projects with industry and international partners. “We work with players in the energy and automotive sectors, and more recently we have also started new projects around data centres and solar energy.”

From underground telescopes to space

The applications of power electronics reach far beyond consumer electronics. Today, Wilmar and his team are involved in projects that stretch from deep underground to far into space.

On one side, the team contributes to the Einstein Telescope, a future gravitational-wave observatory deep underground. “That installation is extremely sensitive,” says Wilmar. “That means the power supply must also be extremely precise. We design how energy gets from the grid to the system: how many conversion steps are needed, how to build in redundancy, and how to guarantee stability.”

At the other end of the spectrum, the team is working with the European Space Agency (ESA). “We are developing power electronics for space applications, such as launch systems and future missions to Mars.”

“It may not be the most visible technology,” Wilmar says, “but without power electronics, many of today’s energy technologies simply would not work. That is what makes this field so fascinating: you are working with the same fundamental technology whether it is for a phone charger, a data centre, a telescope or a rocket.”

More compact thanks to planarmagnetics

Coils and transformers largely determine the size and weight of power electronics. Traditionally, these are bulky parts made from copper and magnetic materials.

In 2025, EnergyVille worked on innovative designs such as planar magnetics, where windings are integrated into printed circuit boards. Combined with new materials and optimisation techniques, this leads to more compact designs, better heat dissipation, and higher power density.

Less energy loss, less heat

One of the central challenges in power electronics is reducing energy losses during conversion. Those losses usually appear as heat, which then must be removed.

In 2025, further work focused on efficient converter topologies such as the Dual Active Bridge (DAB), combined with GaN (gallium nitride) semiconductors. These allow higher switching frequencies with lower losses, making systems more efficient, more compact and cooler in operation.