British billionaire Sanjeev Gupta expects to begin construction of the Cultana solar energy project which encompasses 780,000 solar panels near the revived Whyalla steelworks early in 2019 as part of a broader $1.37 billion investment into renewable energy projects in the Spencer Gulf region in South Australia.

Mr Gupta, the executive chairman of GFG Alliance, outlined on Wednesday fresh details of his renewable energy investment plans for the Whyalla region, with the 280-megawatt Cultana Solar Project the centrepiece of a $US1 billion investment program by his majority-owned renewables company SIMEC ZEN Energy. The plans also include a separate co-generation plant at the steelworks using waste gas, and pumped hydro projects at the nearby Middleback Range mining operations that supply feedstock to the steelworks.