The article is devoted to the actual problem of optimal reservation of generating capacity of electric power systems. One of the approaches to choosing the size of the reserves of generating capacity is presented, which would provide a level of adequacy (probability of failure-free operation) that meets the adopted standard for satisfying consumers with electricity. In this paper, the situation with the level of reservation of generating capacity is analyzed using the example of the IPS of Siberia. Based on the proposed approach, the reservation levels of generating capacity for three values of the probability of failure-free operation are determined: 0.996; 0.999 and 0.9997.

Key words: electric power industry, reliability, adequacy, capacity shortage, transmission line capacity, generation capacity reserve, «locked» capacity.