New Delhi, Oct. 1 -- Tajikistan is building what is set to become the world's tallest dam, a vast hydropower project that could reshape the country's electricity system.

The Rogun Hydropower Project, being built on the Vakhsh River, involves a 335-metre-high rockfill dam with a clay core. Once completed, the structure will be taller than the current world's tallest dam and will form the centrepiece of Tajikistan's plans to expand renewable electricity generation, reduce winter power shortages and increase electricity exports.

The project is already generating electricity even though construction of the dam is still underway. Two of the six planned generating units are operational, allowing Tajikistan to increase electricity production a...