Mankind uses renewable and irrenewable sources to cover energy consumption. In spite that irrenewable ones are more suitable from the viewpoint of the environment they will not represent a larger part. Energetic conception of Slovakia up to the year 2005 takes into account mainly irrenewable sources. The task of its actualization is except the evaluation of the present state and fulfilment of set aims of energetic policy also the evaluation of possible variants of the development from the viewpoint of the influence of their utilization on the environment. This evaluation contains: 1) main obligations of the SR, accepted agreements and conventions in the field of air protection; 2) short description of the methodology of CO2 calculation from fossil fuels; 3) calculation of CO2 production from combustion process and conversion of fuels for the variants 1, 2 characterized by different degree of application of nuclear sources; 4) evaluation of possibilities of fulfilment of obligation of SR following from the Frame Convention about change of the climate; 5) evaluation of possibilities of fulfilment of the National Aim.