A $1 billion battery and solar farm will be built at Morgan in South Australia's Riverland by year's end in a project the proponents describe as "the world's biggest".

The builder, Lyon Group, has already proposed a smaller solar farm and battery storage facility, named Kingfisher, in the state's north.

Lyon partner David Green said the project was 100 per cent equity financed and construction would begin within months, employing 270 workers.

"Riverland Solar Storage's 330-megawatt solar generation and 100-megawatt battery storage system will be Australia's biggest solar farm with 3.4 million solar panels and will also include 1.1 million batteries," he said.

Mr Green said land had already been secured and grid connection was already well advanced.

Work on Lyon's 120 megawatt Kingfisher project is slated to begin in September next year.

"If the 4.7 million solar panels at Riverland and Kingfisher were placed end to end, they would reach from Adelaide to Brisbane and back, and then all the way to Melbourne," Mr Green said.

Mid Murray Council chief executive Russell Peate said such an announcement in this "day and age of employment" was "brilliant" news for the region.

"From an employment perspective, that will have a massive effect on the Riverland and particularly Morgan," he said.

"We will need to work with the developer in terms of accommodation, but it will also impact on school enrolments, the Country Fire Service, ambulance volunteers — and that will be fantastic for that area."

Lyon partner David Green with Treasurer Tom Koutsantonis [L] and Premier Jay Weatherill [R]. ( ABC News: Nick Harmsen )

Lyon to bid for SA battery tender

The Lyon Group has already signalled its intention to bid for a SA Government tender to build a battery storage system with 100-megawatt output.

The Lyon Group has already proposed a smaller solar farm and battery facility in the state's north. ( Supplied: Lyon Group )

The tender arrangement would give the Government the right to tap the battery storage at times of peak demand, but allow the project owner to sell energy and stability into the market at other times.

An expressions of interest process closes on Friday.

Other companies, including Carnegie, Zen Energy and Tesla, have all suggested they could be interested in bidding.

Mr Green said the outcome of the tender would not determine whether or not Lyon's projects were built, but would influence the final storage configuration in terms of the balance between optimising grid security and capture of trading revenue.

"The South Australian Government's leadership on large-scale battery storage has come together with technology cost reductions and international financial interest to provide a timely solution to some of the challenges in the state's electricity system," he said.