Fluctuations of river runoff and power production of Russian hydroelectric stations

Conclusions

• 1. Reservoirs reduce natural fluctuations of river runoff and provide a reliable water and power supply to the population and industry as well as substantially reduce flood losses.

• 2. Reservoirs, redistributing the runoff from the wet season to the low-flow period, provide stable winter production at hydrostations and covering of the load curve of the power system during maximum power consumption.

• 3. The regulating storage of reservoirs is insufficient for substantial equalization of fluctuations of the annual runoff of rivers and, accordingly, annual production at hydrostations. Thus, the annual runoff of the Volga at the site of the Volgograd hydro development in a dry year of 90% probability is 38% less than the average annual value, and the design total annual production of the Volga-Kama hydrostations of 90% probability is only 20% less than the avarage annual. On the Angara, where the country's largest carryover reservoirs are located, the runoff of a dry year of 90% probability is 30% less than the average annual value, and the design total production of Angara-Yenisei hydrostations of 90% probability is only 11% less than the average annual.

• 4. Along with reservoirs, territorial asynchronism of runoff fluctuations have an equalizing effect on total production of hydrostation. The total annual production at Russian hydrostations of 90% probability is only 7% lower than the average annual. However, such equalization of production become real only in the case of uniting regional power systems into a national system with a sufficient capacity of the transmission lines.