The unprecedented decline in precipitation during the past water year (Sept. 23, 2017-Sept. 22, 2018) and years of drought have caused a steep decline in the water stored in hydroelectric dams. As a result, energy produced at 53 hydroelectric power plants in summer fell to 3.65 million megawatt hours, indicating a 36% reduction compared to the corresponding period last year, the Energy Ministry said.
Last water year was one of the driest in half a century because a rainfall deficit of 45% was recorded in winter, Mehr News Agency reported.
Furthermore, the Persian Gulf basin, which produces about 86% of hydroelectricity, experienced the worst conditions among the six major basins in Iran, which include the Central Plateau, Lake Urmia, Lake Hamoon, and Kara-Kum.
The unusual hot summer led to much higher power consumption across the country. On the other hand, there was a 42% reduction of rainfall in the Persian Gulf basin during the last water year compared to the year before as a result of which hydroelectric plants lost much of their ability to produce power. Higher consumption on the one hand and shortage of hydropower on the other led to blackouts in some major urban areas.
Hydropower is a renewable energy and its production is cleaner compared to other power plants. It constitutes almost 15%, or nearly 12,000 MW of total installed power generation capacity of 77,000 MW.
The national energy mix is dominated by thermal power stations. It includes 1,000 MW of nuclear and less than 500 MW of renewable power.
Plans for higher power production are contingent on upgrading the aging power plants with advanced and efficient turbines and a mix of new thermal and renewable power.
Iran hopes to add 5,000 MW of new capacity a year by the end of its Sixth Five-Year Economic Development Plan in 2022.