23.08.2021 | Trainee alumni at Axpo: Sandro Renggli

“Your learning path never ends”

Noa Frey





Sandro Renggli studied electrical engineering at ETH and is part of our 7th trainee generation. After completing his data science traineeship in the power divisions of Axpo, Sandro is now making an impact at Axpo as a digital engineer. He is passionate about complex systems and finds that there are few as complex as those in energy. 

Sandro Renggli

Function: Digital Engineer

Trainee Alumni: Trainee Data Science Power

Background: MSc in Electrical Engineering an der ETH 

Assignments: Realtime-datapipline for Grid 4.0 / Hydro 4.0, asset management for the hydropower area, business model innovation for the Axpo subsidiary CKW

During his studies Sandro worked part-time for Semax, a Swiss smart meter solutions company. At the same time, he focused on the application of machine learning algorithms to energy system challenges in his academic projects. “After those experiences, I knew I wanted to work in the energy sector, but the field is so broad, I did not know where to start. A traineeship, where I could explore different topics and then decide what I liked best sounded perfect to me”. Sandro had the chance to dip his toes into the topics of business intelligence tools and IoT data pipelines. He could then follow his love for data science and machine learning working at Axpo’s subsidiary CKW during his traineeship. 

Why did you select a traineeship at Axpo?

The broad insights into the different responsibilities of a big company in the energy sector drew me towards a traineeship at Axpo. 

What are the benefits of a traineeship from your perspective?

Thanks to the rotations in the traineeship, you get a more universal and a clear understanding of the whole life cycle of electric energy. On top, you can build up a group wide network of people, which is very valuable in later projects. 

Can you tell us more about the different rotations and projects during your traineeship?

I started in the teams of Hydro 4.0 and Grid 4.0. My main topic was the conception and realization of a real time data pipeline from our control systems to our newly built cloud infrastructure. In my second rotation I gained project management experience within the asset management of the hydro power plants. I concluded my traineeship at CKW, a subsidiary of Axpo, where I used my data science skills to generate new insights in the smart energy customer journey, as well as the performance of different sales channels.

What impact did your traineeship have on Axpo? What is your “footprint”?

Together with my colleagues, we built the basics for streaming real time data from our hydro and grid control systems to the cloud environment. In addition, I was able to come up with some completely new approaches to analyze the customer journey of some of our clients at CKW.

What is a typical day as a trainee at Axpo, and what are the highlights?

It sounds pretty simplistic but one of the things I appreciated most during my traineeship was the fact that I was perceived as a fully-fledged team member. Right from the start, you take on responsibility for your projects and your opinion is appreciated in the team discussions. 

Sandro Renggli and Mathias Pawlowsky
What was something you didn’t know before you started working at Axpo?

I did not know how diverse and interconnected Axpo’s business is. A lot of different topics come together in one place: technical tasks, economic questions, legal concerns, political aspects and so on. This makes your daily work interesting but at the same time quite challenging.

What did you apply in your daily work, that you learned at university?

Never believe that your learning path ends when you start your professional career. In the area of digitalization, you have to be curious all the time. At university I got the skill to adapt quickly to new situations, as well as to quickly catch on to new topics. This helps me a lot in my daily work. What helps me as well is my technical understanding of an energy system which allows me to grasp new tasks quickly. Last but not least, to be able to program Python is a skill which is vital in my daily business.

What would you recommend graduates do at the start of their career? 

It is really beneficial to be able to code or have some IT skills. I wish I had devoted more time to this area during my studies, even though at Axpo I had ample access to resources to speed up my learning process in this field. It is never too late to learn a new skill, if you put your mind to it. I taught myself how to use machine learning algorithms in Python in just a few weeks during my master’s degree.

Did Sandro’s experience of a traineeship at Axpo spark your curiosity? You can find more information here. We hope to meet you during the recruitment process soon!

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