ABSTRACT
The aim of the article is to present the probabilistic energy security assessment methodology and to provide a comparison of energy security of the development scenarios of the electricity generating system. A model of disturbances formation from the threats and a model of development of a disrupted energy system as well as the algorithm of calculation the energy security coefficient is presented. The energy security assessment of the Lithuanian electricity system is presented in the paper as well. A few scenarios for development of the electricity system are analysed: different technologies installation to electricity generation of which can be supported by quotas or implemented as commercial projects and the possibility to participate in electricity market. Disturbances as different energy supply disruptions and increases of their prices are analysed in the model and their impact on energy security is analysed. resistance to disturbances
