Corporate Responsibility

Susann Terheggen


The man on the roof

Chris Mathea regularly climbs on DT's rooftops - that's part of his job. He's responsible for equipping our locations with renewable energy sources. In our interview, he explains why installers fear him, what's most annoying in his job and why photovoltaics in Munich caused five police alerts.

Chris Mathea in front of a magenta illustration with windmills and solar panels.

Chris Mathea is responsble for building up renewable energy sources at DT. © Deutsche Telekom

You are responsible for renewable energy in the company. What is your job description: business economist, engineer, or environmental activist? 

Chris Mathea: Probably a little bit of everything. I studied business informatics and became an electrician master through a second educational path. And the fact that I am very interested in photovoltaics privately also fits well with the job at Power and Air Solution Management (PASM).

Keyword "Use what you sell": Do you also have a PV system at home? 

Chris: Of course, even with a facade PV system. By the way, it's very practical because a vertical solar module is cleaner and more efficient in the winter months. I have also installed nine systems myself at  my friend's  houses. That's why I'm not the most popular person among the solar companies that work for us. Because I know when they make things more difficult than they actually are.

What about at Telekom: Does solar fit on every roof? 

Chris: No. Some of our roofs are 70 years old or older. That is a static challenge or not profitable. But there are 8,000 roofs that have the potential. In addition, there are 400 open spaces, like green meadows. Fortunately, because we have to build where we can. Currently, we produce one percent of our electricity needs from renewable energy sources. However, our goal is to reach ten percent by 2030. For comparison: That is as much as 100,000 two-person households consume in a whole year. Since photovoltaics is easier to install compared to wind power, our focus is primarily on that.

Do we already have a wind turbine somewhere? Maybe in the coastal region? 

Chris: Almost. In Leichlingen near Leverkusen. This also brings us some trouble reports at the service hotline - because it doesn't turn.

And why not? 

Chris: That's a curious story: Deutsche Funkturm used the wind turbine as a mobile phone mast. They no longer needed it, so they deactivated the whole turbine. We are currently working on reactivating the site, but we want to put a more powerful system there. To give you an idea: With just one rotation of the turbine, the battery of an electric car would already be 50 percent charged. And that's nothing compared to large turbines like the ones in China: They can charge five batteries with one complete rotation.

Sounds good - what's stopping us then? 

Chris: Bureaucracy. It is definitely the worst part of my job! In order to even get into the vicinity of an approval process, you have to invest 80,000 euros in various expert opinions. And then we feel every day how slowly the wheels turn in Germany. Fear, ignorance and a lack of knowledge are definitely not decision accelerators. In addition, there are often complaints from residents, not only regarding wind power...


Chris: In Einsteinstraße in Munich, we had a PV inverter on the roof. The device ensures that the solar power is usable at all. Because of this, residents from the opposite building called the police five times, complaining about alleged noise pollution. The catch: The system was not even connected at that time. We have since relocated the inverter inside the building.

240402_Besondere Momente 2023

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