The consumption of hydrogen in petroleum refineries is increasing due to its growing intensive use in treatment processes and in new refining technologies. This trend and the reduction of hydrogen production in gasoline processing have generated a new panorama. In this new context, target identification for minimum consumption of hydrogen in a distribution network has become fundamental information in the definition of minimum hydrogen requirements in petroleum refineries. This paper presents the hydrogen source diagram (HSD), a new algorithmic method for minimum hydrogen consumption target calculation and, simultaneously, hydrogen network flowsheet synthesis. The proposed HSD procedure is described in details using a case study, showing its wide scope. The results demonstrate the effectiveness of the procedure and show that the generated network can be easily adapted to meet specific plant restrictions.