A battle royale is set to erupt in green energy.

At the Reliance Industries’ virtual AGM on Thursday, Mukesh Ambani said the company would invest Rs 75,000 crore in renewable energy — which will pit him against Gautam Adani, whose group has set itself the target to be the No.1 solar company in the world by 2025 and a top renewable energy player in the world in another 10 years.

Reliance’s ambitious plan in new energy was the key theme at the 44th annual general meeting (AGM) of the company with chairman-cum-managing director Ambani claiming they will make new energy a “truly global business’’.

Addressing the shareholders, Ambani said Reliance has started work on developing the Dhirubhai Ambani Green Energy Giga Complex on 5,000 acres at Jamnagar. This will be amongst the largest such integrated renewable energy manufacturing facilities in the world. It will have four “giga factories” that will manufacture and fully integrate all the critical components of the new energy ecosystem.

The term giga factory was first coined by Elon Musk, the Tesla chief, when the company began work on its huge battery unit outside Sparks, Nevada.

In solar energy, RIL will build an integrated factory to make solar photovoltaic modules or solar panels. It will also build an advanced energy storage battery unit.

There will be an electrolyser factory to manufacture green hydrogen, while a fuel cell unit will convert the hydrogen into energy.

“Over the next three years we will invest over Rs 60,000 crore in these initiatives. Reliance will thus create and offer a fully integrated, end-to-end renewables energy ecosystem,’’ the RIL chief said.

The Jamnagar complex will also provide infrastructure and utilities to manufacture ancillary material and equipment needed to support the Giga factories.

Reliance will also support independent manufacturers to be part of this ecosystem. It will invest an additional sum of Rs 15,000 crore in value chain, partnerships and future technologies, including upstream and downstream units.

“Thus, our overall initial investment from our own internal resources in the new energy business will be Rs 75,000 crore (over $10 billion) in three years… Jamnagar was the cradle of our old energy business. Jamnagar will also be the cradle of our new energy business,’’ Ambani said.

The Adani group, which is present in solar power, wind power and hybrid power — harnessing both wind and solar energy — and solar parks, had also announced its venture into the lithium battery segment earlier.