Power bills for households in South Australia could fall by about $66 a year if a new interconnector is built with NSW, transmission company ElectraNet says.

The company has released its final report into the project which also suggests power costs in NSW could fall by about $30 a year.

Savings to small business customers in SA are projected to be about $132 annually and in NSW about $71.

“The new interconnector would lower wholesale electricity costs in both states, improve network and energy security and support Australia’s energy transformation towards a low carbon emissions future,” ElectraNet chief executive Steve Masters said on Wednesday.

The project is subject to obtaining all necessary approvals, including those from the Australian Energy Regulator which is expected to make a final decision mid-year.

It would be built by ElectraNet and TransGrid, the operator of the high voltage transmission network in NSW.

Their plan is to follow a 900-kilometre route between Robertstown in South Australia and Wagga Wagga in NSW.

ElectraNet says independent modelling suggests the project would create more than 1000 jobs across the two states during construction.

TransGrid chief executive Paul Italiano said the project would play a key role in delivering energy security and better consumer outcomes.

“Project EnergyConnect will be a key plank in developing a more connected National Electricity Market, with significant benefits through access to more energy supply and increased competition in the market,” he said.