The 1st CPOTE conference, held in 1998, was dedicated to the 50th Jubilee of Prof. Szargut's scientific activity. The 2nd one (2004), was connected with the celebration of centenary tradition of the Institute of Thermal Technology, reaching back to the Technical Universitiy of Lviv. The 3rd CPOTE conference (2012) was connected with the jubilee of Professor Andrzej Ziebik's 50 years academic activity. The 4th CPOTE conference (2016) was devoted to the topic Sustainable Energy Systems for our Common Future and it gathered over 100 participants from all around the globe. The 5th CPOTE conference (2018) is dedicated to the Memory of Professor Jan Szargut.