The Faculty of Energy Engineering celebrated the 75th anniversary of the birth of Prof. Dr. Eng. Valentin Obretenov

On 24.06.2025, in a solemn ceremony in front of Block 11 of the Technical University – Sofia, a monument was unveiled in connection with the 75th anniversary of the birth of the prominent Bulgarian engineer, Prof. Dr. Valentin Obretenov. 

In his speech, the Dean of the Faculty of Energy Machinery, Prof. Dr. Eng. Angel Terziev, spoke about the academic development and scientific achievements of Prof. Obretenov, who dedicated his life and talent to one of the most important spheres for society – hydropower. The Dean highlighted Prof. Obretenov's contributions to the design and organization of the entirely new laboratory for hydraulic machines in Block 11 of TU – Sofia, whose construction became the work of his life. The laboratory, which is still used today for student training and scientific research, complies with the IEC 60193 standard, enabling model testing and the development of models for various types of water turbines. Prof. Terziev further added that Prof. Obretenov collaborated with numerous companies on the design of water turbines and the modernization of facilities in HPPs in Bulgaria and abroad. He is also credited with creating and implementing a measurement system for field testing of water turbines, pumps, and hydropower systems. In conclusion, the Dean noted that through his developments, innovations, and years of hard work, Prof. Obretenov has left a lasting imprint on the country's energy system.

Prof. Terziev expressed special thanks to the National Electric Company for the generous donation of a runner from a Francis-type turbine, which is also one of the proofs of the ongoing successful cooperation between the university and the industry.

Prof. Dr. Eng. Rositsa Velichkova, Head of the Department of "Hydroaerodynamics and Hydraulic Machines" at the Faculty of Energy Machinery, expressed her satisfaction and gratitude for the unveiling of the monument to Prof. Obretenov, which remains an integral part of the department's history due to his scientific achievements and long-term teaching activities.

A greeting on behalf of Georgi Dobrev, Executive Director of "National Electric Company" EAD, was read by Ekaterina Boneva – Head of the "Production Planning and Maintenance" Department.

Colleagues and friends of Prof. Obretenov shared memories of his personality and work – Nikola Neshev, Assoc. Prof. Todor Chakarov, and Prof. Ilcho Angelov.

The ceremony was attended by faculty members, doctoral students, and staff of the Faculty of Energy Machinery, colleagues and former students of Prof. Obretenov, business representatives, his friends, and relatives.

The unveiling of the monument is not only a tribute to a professional but also a symbol of deep gratitude for the contribution and personality of Prof. Valentin Obretenov, and part of the efforts of the Faculty of Energy Machinery to honor significant personalities and values that have contributed to the development of the academic and public environment.