Proponents say a new electricity interconnector between South Australia and New South Wales will lower power costs and improve security.

The Project EnergyConnect plan includes a $1.52 billion, 900-kilometre link between Robertstown, north-east of Adelaide, and Wagga Wagga, in New South Wales, running through Buronga, north-east of Mildura.

It also covers an additional line between Buronga and Red Cliffs in Victoria, south of Mildura.

Its proponents ElectraNet and TransGrid says the project could cut power bills by $66 a year for South Australian households and $30 in New South Wales.

The project has been submitted for approval by the Australian Energy Regulator.

The companies behind it have issued reports saying the new interconnector would enhance “security of supply for South Australia” and “diverse low-cost renewable generation sources to New South Wales”.

The new interconnector could be built by the time the coal-fired Liddell Power Station retires from the market in New South Wales.

It may also provide additional transfer capacity for the sharing of reserves between South Australia, Victoria and New South Wales.

South Australia says it wants to be part of a greater network.

“We need to become part of the loop,” said SA Energy Minister Dan van Holst Pellekaan.

“Interconnection between South Australia and New South Wales would give us much greater flexibility to share demand and supply with two states rather than just one.

“Also very importantly we will be connected to a state that has more different weather patterns than us, so that our demand and supply is different more often meaning we can economise, optimise and share electricity.”

The SA Government is reportedly underwriting early works, and has agreed on a framework with the NSW Government to expedite the project to be completed by 2022.