Team

Stefan U. Ciupek – Managing Partner & CEO
Stefan brings more than 25 years of experience in renewable energy and BESS development across CEE and the DACH region. A graduate of the University of Vienna and Hawaiian Pacific University (USA), he has successfully developed, financed, and operated large-scale RES and EE projects across Europe. He also served for 13 years as Financial Verificator for the EBRD in programs worth ~€700m, gaining deep insight into EBRD standards and financing structures. At Nawitas, Stefan focuses on strategic growth of ESSCo-model BESS projects, investment structuring, and partnerships.

Lubomir Polonec – Managing Partner & CTO
Lubomír has over 20 years of experience in RES and BESS development, primarily in Slovakia. As a Chartered Energy Auditor, he advises industrial clients, public buildings, and municipalities. He also consults for the EBRD, UNIDO, and the European Commission on low-carbon transition strategies. Author of numerous publications, he collaborates with the Slovak University of Technology in Bratislava. His expertise bridges academic research and real-world BESS deployment.

Rafał Darski – Managing Partner & CFO
Rafał is a senior executive with 20+ years of experience in energy and finance in Poland and abroad. He holds an MBA from the University of Poznań in cooperation with Georgia State University, Atlanta (USA). At Nawitas, he leads Polish BESS development and operations. His expertise spans project financing, strategy, and business growth across startups and corporates. With a strong track record in scaling energy businesses, Rafał strengthens Nawitas’ ability to expand ESSCo projects across Central Europe.

C-Level Experience: Collectively, the team brings more than 65 years of expertise in energy infrastructure, grid services, and B2B projects.