PAPILIO

You mentioned that PAPILIO being powered by renewable energy came up later. How did you make that switch?

While researching light pollution, I also came across another major issue related to public lighting: energy usage. 

In Germany, for example, about 2% of primary electricity is used just for powering public lighting. That translates to roughly 2.5 million tons of CO₂ emissions every year from streetlights alone. Seeing that number made me realise how impactful it could be to change how streetlights are powered. 

Some places already use solar-powered streetlights. But in northern regions near the sea—like Scandinavia, northern Germany, or the Netherlands—it’s a different story. In winter, the nights are very long, and sunlight is limited. However, these areas tend to be much windier. 

That led me to the idea of incorporating wind power as an alternative to solar—something better suited for darker, windier regions. And since every streetlight already has a tall pole, the infrastructure for installing small-scale wind turbines is already in place. 

Your wind-powered streetlight helps protect biodiversity using wind energy. What do you see as its most important innovations?

First, the light spectrum contains little to no blue light, making it less attractive to insects and other animals. Second, the demand-dependent lighting control uses infrared sensors to switch the light off when no one is nearby. While some solutions for these issues already exist, I combined them into one product. 

A key advantage is that it works completely autonomously, independent of the public power grid. You can place it anywhere, and it generates all the energy it needs. It has a vertical-axis wind turbine that spins regardless of wind direction, generating energy stored in a battery integrated into the lower part of the pole. That battery can power the light for up to three days without wind. At night, it powers a warm-spectrum LED, which is less harmful. 

The lighting control adapts to the environment’s brightness—turning on earlier when it’s cloudy, later when it’s sunny—and dims after 1 or 2 a.m. when fewer people are around, to minimize unnecessary use.

 Beyond materials, who you work with is just as important. Are city planners or municipalities your key clients or collaborators?

Yes. This field is a bit different from other design areas because it depends on cities. We’re talking about public spaces, after all. It’s not like private individuals pick out a streetlight and install it themselves. It’s always cities, communes or planning offices working on behalf of the city or state. So, our main target group is policy decision-makers and city governments. 

Most people working in this field already understand the importance of implementing new solutions. Money isn’t always the problem. There are often substantial funding pots available for city planning. What we need is to inform people about what’s possible and educate them on the harm caused by current systems. 

It’d be great to connect with as many people as possible who are involved in urban planning and city infrastructure and who want to help rethink how we light our cities. 

Since people in urban planning and city infrastructure are PAPILIO’s main target group, how do you see the business model evolving?

We did some calculations. The biggest advantage is that you don’t need underground electricity infrastructure. So, if you’re installing lights in places without an underground power grid—like natural environments or remote streets—it might already be cheaper, or at least cost the same, as traditional streetlights. 

Small-scale wind power is still a relatively new field—especially compared to solar, where prices have dropped dramatically in recent years. Right now, we’re working with very small quantities, which makes everything more expensive. But we hope this becomes a serial product, and then the price can drop significantly. 

So yes, it’s currently a bit more expensive than a regular streetlight. But I think if cities are serious about sustainable transformation, it’s worth paying a bit more to get all these positive benefits at the same time.