The planned construction of a $360 million gas-fired power station in South Australia has attracted worldwide interest from 31 companies, with the expression of interest process now closed, the State Government says.

The 250 megawatt power plant is a key part of the Government's $550 million plan to secure the state's energy supplies.

Premier Jay Weatherill said in just two weeks there had been interest to build it from many countries, including Australia, China, Malaysia, Singapore, France, Finland, Spain and the UK.

"It demonstrates the extent to which this has become an international quest for grappling with South Australia's energy future," he said.

Mr Weatherill said laws to give the energy minister new powers to intervene in the electricity market, including the right to order power stations to switch on, would come into effect on April 26.

Meanwhile he said 90 expressions of interest had been received to build "Australia's largest battery" — which is another plank of the Government's energy plan.

"We're not waiting around for the National Government to get its act together — that's why we're taking charge of our energy future," Mr Weatherill said.

"We're standing on our own two feet, we're becoming more self-reliant and we're getting busy with acting on the plan."

The Government's energy security plan aims to stabilise the state's electricity grid in the wake of events, such as the statewide blackout, and make power more affordable.

Some price relief may be in sight for households, with Electranet announcing consumers can be expected to save $14 on the transmission component on their annual electricity bills.

Chief executive Steve Masters said small business would save $28 in the first year of the five-year revenue proposal.

"Our revenue proposal is designed to deliver on the long-term interests of customers," Mr Masters said.

"Electranet is investing in the transmission network to support the safe, secure, reliable and affordable supply of electricity into the future."

ACCC grants SA businesses permission to group-buy power

A group of 24 South Australian businesses, including Arrium, Adelaide Brighton Cement and Foodland, are seeking their own respite from high power costs and have been approved to set up their own joint electricity purchasing group.

The Australian Competition and Consumer Commission (ACCC) has proposed to grant authorisation for 11 years and it is allowing the parties to start a joint tender for the supply of electricity straight away.

The joint buying group accounts for about 15 per cent of electricity demand in South Australia and the businesses have joined forces to try to secure reliable and affordable electricity supply arrangements.