Public attitude towards renewable energy sources (RES) has positively changed in recent years. Determining factors are the rapid growth of energy demand, depleting fossil fuels resources and the negative effects of climate change. The purpose of this paper is to examine public perceptions concerning knowledge on various forms of RES, understanding of RES advantages and RES contribution to improving life quality. Data was collected via questionnaires given to postgraduate, undergraduate students and personnel in the area of the Piraeus University of Applied Sciences. Research hypotheses were analyzed, according to the relevant literature. Factor analysis was used for locating the factors influencing attitude on RES. Results reveal that there is a positive attitude towards RES, especially for the case of solar energy. Also the majority of the sample believes that RES can contribute in life quality improvement. On the other hand, most respondents declared that the major obstacle for RES expansion is lack of information which leads to public apathy. An interesting finding is that most respondents consider that investments in RES are difficult to be implemented by individuals.