This study presents a general computer program developed for performing a preliminary evaluation of small hydroelectric (SHE) system installations providing the user with sufficient technical and financial information in order to justify further investment in such installations. It also assesses pertinent non-financial attributes, such as local/national environmental and socio-economic impacts. The program also takes into account the specific technoeconomical constraints applicable in Greece. As a case study, a SHE installation in the geographical area of Central Macedonia of Greece, is thoroughly analyzed.