Green hydrogen and the price of water: a scenario assessment for the Caspian region of Kazakhstan

Аннотация

This article examines the water implications of large-scale green hydrogen production in the Caspian region of Kazakhstan. The study focuses on Mangystau Region and uses the publicly announced scale of the Hyrasia One project as a case study. A screening-level scenario method is applied to estimate annual and daily water demand at three water-use intensities: 9, 15, and 20 litres per kilogram of hydrogen. At the planned output of up to 2 million tonnes of hydrogen per year, the estimated demand ranges from 18 to 40 million m³ annually, or approximately 49,000–110,000 m³ per day. The central scenario of 30 million m³ per year is higher than the design capacity of the 50,000 m³/day Kenderli desalination plant and therefore cannot be treated as a minor local utility demand. At the same time, the electricity required for seawater reverse osmosis would represent only a small share of the renewable electricity announced for the hydrogen complex. This means that the main constraints are not only energy costs, but also water allocation, intake and brine-discharge impacts, infrastructure timing, and coordination with public water supply. The article concludes that hydrogen planning in western Kazakhstan should be linked to integrated water resources management, a dedicated non-potable water supply, environmental monitoring, and staged project development.