Hindustan Zinc Ltd plans to invest $2.5 billion (Rs 20,900 crore) to double its annual production capacity to 2 million tonnes of zinc, lead and silver, Chief Executive Officer Arun Misra said in an interview.

The expansion is expected to start in the first quarter of the next fiscal year, he said.

"Expansion will be brownfield with the existing mines, while greenfield will be a new smelter with up to 0.6 million tonne capacity. The rest of the capacity will come from expansion or de-bottlenecking of the existing smelters," Misra said on the sidelines of Zinc College 2024, an event organised by the International Zinc Association (IZA) in Udaipur.

HZL hired two Australian mine-planning and mine-contracting firms to develop a plan for doubling the capacity of its mines, Mint reported in July. The company has also engaged a consultant to work on expanding its zinc smelting capacity — a mix of greenfield and brownfield diversification — Misra added.

The 58-year-old company operates six mines, all of which are located in Rajasthan. It has three smelters. Zinc smelting alone accounts for 913,000 tonnes per year, according to the company's latest annual report.

IZA has forecast a significant rise in zinc demand in India by 2030, driven by emerging sectors such as renewable energy and battery technology coupled with infrastructure, steel and automotive. "We are optimistic that zinc demand to double in less than 10 years," said Andrew Green, Executive Director, IZA.