In this work the CO2 emissions due to the University of Perugia's energy needs have been evaluated. Perugia is a city set in the middle of Italy, in the 'Umbria' region, with a population of about 1 400 000 people. The University of this city was founded in 1260 and nowadays consists of eleven Faculties with 30 000 students and about 1200 teachers. The energy needs of the University are mainly due to thermal and electrical users. In particular, the thermal consumption is strictly connected to building heating in the autumn-winter months. The reduction of CO2 emissions is one of the main goals that developed countries have established to be achieved in the next few years, not only related to the Kyoto treated goals, but also for increasing economical and industrial production with a sustainable development concept. Carbon dioxide is not strictly a toxic substance, but makes a large contribution to the 'greenhouse effect' with negative repercussions for the environment. For these reasons the possibility of satisfying the University of Perugia's energy needs by the adoption of one, or more, cogeneration power plant fuelled by natural gas, opportunely located at the University, has been evaluated both in terms of energy production and of CO2 emission reduction. This study also takes into account the experiences of the cogeneration power plant that is in operation at the Engineering Facility of Perugia University. The results have been compared with the Regional Energetic Development Planning for evaluating the influence of the University's energy needs and emissions on the whole Region. Copyright (C) 2001 John Wiley & Sons, Ltd.