Thirteenth International Water Technology Conference, IWTC 13 2009, Hurghada, Egypt 703 ENERGY SAVING MODEL IN A WASTE WATER TREATMENT PLANT - A PILOT STUDY Monica Popa 1 , Dana Sîrbu 1 , Daniela Cureu 1 , and Marcel Sabin Popa 2 1 University of Medicine and Pharmacy Cluj-Napoca, Romania Dept. of Environmental Health Pasteur str., 6, 400349 Cluj-Napoca, Romania, E-mail: dr_monica_popa@yahoo.com 2 Technical University of Cluj-Napoca, Romania Baia-Mare str., 25, 400171 Cluj-Napoca, Romania E-mail: marcel.popa@tcm.utcluj.ro ABSTRACT The main objective of this pilot study is to reduce the global warming effect of the atmosphere by the reduction of the CO 2 emissions. With this aim specific energy saving measures are projected for implementation at the municipal waste water treatment plant of Cluj-Napoca. It will result a fully operational combined heat and power unit working on the biogas generated in the waste water treatment process. Keywords: wastewater, treatment plant, biogas, greenhouse effect. BACKGROUND OF THE ROMANIAN WATER SECTOR In the last years the general approach regarding the water sector in Romania recorded important changes. In order to assure a sustainable development of the water sector and the compliance with the EU Directive according to the agreed conformation period for the entire territory of Romania, it was adopted a consolidation approach for the operation of the water and wastewater systems as part of a regionalization strategy. After a period of more than four decades of centralized management, Romania decided to return to the local autonomy principle through decentralization, in this way transferring major and concrete responsibilities to the local public administration. One of these specific responsibilities mentioned in republished, refers to the obligation of local administrations to organize their operation efficiently and adequately in order to provide public services (Law of the local public administration [1]). A number of 32 major municipalities (of more than 100,000 inhabitants each) have benefited from capital investment programmes for rehabilitation of their water and wastewater infrastructure between 1990 and 2007. In Romania, only 70 % of the population is connected both to water and sewage services and more than a half of the wastewater is untreated or insufficiently treated