The audacious scheme to use excess sunshine from the Australian outback to power Singapore did that last week when the Indonesian government importantly approved the subsea cable route linking Australia with its intended customer.

This is Sun Cable, backed by Aussie billionaires Mike Cannon-Brookes and Andrew Forrest, which is expected to cost more than $30 billion to build.

Sun Cable has already secured rights to 12,000 hectares of pastoral land at Newcastle Waters Station near Tennant Creek in the Northern Territory to build the world's biggest array of solar panels to provide power via a yet to be built undersea cable to Singapore.

The project aims to supply about 15 per cent of the island nation's power needs from more than 4000 kilometres away by the end of the decade.

The Consolidated Pastoral Company station still has plenty of land left to run its beef operation which covers more than a million hectares.

Sun Cable also proposes to build a 20-30 gigawatt hour battery storage facility near Tennant Creek.

So confident are the backers, Sun Cable last week said it was expanding its proposal by up to 40 per cent, lifting its potential capacity from 14 gigawatts to between 17 and 20 gigawatts.

Sun Cable also plans to provide renewable power to Darwin via an overhead high voltage transmission line before the cable takes off underwater to Singapore.

If built, the scheme will provide total carbon emissions abatement estimated at 8.6 million tonnes of CO2 each year as well as up to $2 billion in exports for Australia each year, similar to Australia's dairy export industry

The project has received major project status from the Federal government (July 2021) and the NT government (June 2020).

Indonesia's coordinating Minister for Maritime Affairs and Investment, Luhut Binsar Panjaitain confirmed his government has recommended the route of the transmission cables through Indonesian waters, with the Ministry of Transportation granting the subsea survey permit.

To succeed Sun Cable will need to integrate a range of technologies and infrastructure including:

Sun Cable chief executive David Griffin said the Indonesian agreement was a "significant milestone for the project" which aims to clear all necessary approvals and start building work within a few years.

Minister Pandjaitan said Sun Cable's decision to invest more than US$2 billion was expected to bring huge benefits for the Indonesian people.

Sun Cable also committed to support renewable energy development with Bogor Agricultural University and Sepuluh Nopember Institute of Technology, and agreed to support for a scholarship program.

NT chief minister Michael Gunner said the project was building momentum.

Key investor Andrew Forrest said: "Decarbonising our planet is a challenge all people and all nations must rise to. But it is action, not words that are required."

Atlassian Mike Cannon-Brooks said he believed Australia could become a renewable energy superpower.

"We can and should tap into our solar resources that could power the world five times over," he said.

"Securing Indonesian support is a big step towards realising our potential of becoming one of the world's largest energy exporters."