[en] In this part of the study, the environmental impacts caused by energy conversion are analysed. As regards the exposure of specific organs to radiation produced in energy generating plants and plants of the corresponding fuel cycles under normal operating conditions, a quantitative comparison is carried out for different reactor systems and coal-burning energy generating systems. For a model region, the Upper Rhine Region, the radiation dose resulting from the nuclear energy generating capacity planned by the year 1990 is shown. Furthermore, the increase in the global radiation dose due to the world-wide nuclear capacity to be installed by the year 2000 is analysed. To assess the results obtained for the radiation dose the latest data on the biological effects of radiation in human organisms are presented. A further environmental problem treated in this study is the waste heat release from energy generating plants. As a first step towards determination reactor specific emission data sets in case of accidents some basic safety characteristics of various types of reactors are compiled. Moreover, the safety problems associated with the ultimate storage of radioactive waste are discussed. The development of the hazard index as a function of time is shown for various fuel cycles. (orig.)