Horst Theisen is CEO of Rhenac GreenTec AG, a German company specialising in sports turf lighting and pitch management systems. With over 20 years of experience in plant lighting technology and more than 15 years working with plant scientists, engineers and technicians, he is a recognised market leader in lighting solutions for turf growth.

Prior to founding Rhenac, Mr Theisen held senior positions at international industrial companies, including Head of Building Automation at Eaton Corporation Germany. Since 2008, he has led the development of innovative, patented systems and was honoured with the German Innovation Award in 2015.

A key innovation under his leadership is Rhenac’s patented CLS (Complete Light Spectrum) LED system, supported by AI-driven tools for precision turf management. Developed in close collaboration with the Technical University of Munich, CLS replicates the full spectrum of natural light and remains the most advanced solution on the market—available exclusively through Rhenac.

The company collaborates with international sports federations and academic institutions academic institutions, including the University of Michigan. Rhenac’s systems have been installed in high profile sports venues such as the Santiago Bernabéu Stadium and FC Schalke 04’s VELTINS Arena.