Higher education (HE) programs and their home institutions establish alumni networks to keep in contact with their graduates. Objectives to run such networks may stay undefined and rather general. An investigation was carried out to analyze the field of activity and features of the alumni network of the Postgraduate Program Renewable Energy (PPRE) at the University of Oldenburg, Germany. Focus was put to the approaches to run and nurture such a network. Focus was also put on the user behavior. The network was established close to the start of the program in 1987 in form of a closed and supervised emailing list. The PPRE alumni network today is formed by 560 alumni from all batches since the program start. Responses to a survey were returned by 28% of the alumni, naming different interests in the use of the network. Results indicate a positive, self-perpetuating effect on the network development and program recognition based on an extended managing of the network.