Abstract
This paper investigates the influence of the NORIN (Naryn) hydropower cascade on the daily and seasonal load profile of the Eastern Power Interconnection of Uzbekistan. The cascade, comprising Toktogul, Kurpsay, Tash-Kumyr, and Uchkurgan hydropower stations with a total installed capacity exceeding 3,000 MW, plays a pivotal role in peak-load regulation, frequency stabilization, and voltage support across the eastern grid. Using load-flow simulation models and statistical analysis of operational data, the study evaluates the capacity of the cascade to flatten peak-to-valley differentials, reduce thermal plant cycling, and improve overall system reliability. Results indicate that coordinated cascade dispatch can reduce peak loading by up to 22% and decrease frequency deviation events by 35% compared to uncoordinated operation. Recommendations for optimal scheduling of the cascade are presented.