Currently there are four energy generating companies in Armenia which produce more than 80% of electricity in the country. These are the Armenian Nuclear Power Plant (ANPP) (the total gross output capacity of the functioning electro-block is 407.5 MW), RazTES (the gross output capacity is 1,110 MW, functioning output capacity is 760 MW), the Sevan-Hrazdan Cascade Hydroelectric Power Plant (gross output capacity – 550 MW), and the Vorotan Cascade Hydroelectric Plant (gross output capacity 450 MW.) It should be noted that the Yerevan Thermoelectric Plant produces electricity equal to only one turbine capacity of 50 MW and the production is conditioned on the functionality of the Nairi Chemical Plant, to which it supplies steam and heat. The Vanadzor Thermoelectric Plant, with a capacity of 50 MW, is not functioning and can operate only if the chemical complex of Vanadzor is used. In addition, there are several small-capacity hydroelectric plants, but with a total output capacity of 61 MW.
The ANPP is the primary station of the Armenian energy system. Every year the ANPP shuts down for two to three months in order to refuel and conduct preventive maintenance. Meanwhile, RazTES has become the major alternative to meet the domestic demand for electricity.
Within the internal market of Armenia, the Hrazdan Thermoelectric Plant has the status of a balancing station. For internal consumption, the Hrazdan Thermoelectric Plant generates electricity only when a deficit in the Armenian energy system is registered, and this usually occurs in the fall-winter period and when the ANPP stops its operations. At the same time, RazTES is extremely important for electricity export.