The first national audit of batteries that store solar power shows almost 7,000 were installed in Australian homes last year — and that's predicted to triple this year.

Key points: Solar experts say the market for batteries exploded mid-2016

Solar experts say the market for batteries exploded mid-2016 They predict batteries will play an important role in energy networks in a few years

They predict batteries will play an important role in energy networks in a few years Some consumers see batteries as a way to ensure they have adequate power supply

Warwick Johnston from solar consultancy SunWiz carried out the audit by speaking to manufacturers and suppliers.

"There was a significant fall in battery prices mid-way through 2016 and the popularity of batteries just exploded," he told the ABC.

He said with South Australia battling blackouts, batteries would eventually be a "game changer" for Australia's energy networks.

Solar batteries are expensive, but intense competition has brought prices down.

About 20 manufacturers are producing around 90 products for sale in Australia, with the cheapest battery retailing for $1,200.

Many larger batteries still cost between $8,000 and $10,000.

Mr Johnston said batteries held benefits for the entire community, not just homeowners.

He said there was potential for the energy stored in batteries to be put back into the grid for the public to use.

"I'd say three years is when we'd start to see that batteries are playing an important role in the network," Mr Johnston said.

"It's both something that needs to be managed but also something that can present a great opportunity for Australia."

Got a confidential news tip? Email ABC Investigations at investigations@abc.net.au For more sensitive information: Text message using the Signal phone app +61 436 369 072 No system is 100 per cent secure, but the Signal app uses end-to-end encryption and can protect your identity. Please read the terms and conditions.

Solar batteries one way to avoid a blackout

Australia's energy networks have been criticised by some as being unreliable, and some consumers see batteries as a way to ensure they have adequate supply.

Sydney resident Alan Jones was one of the first Australians to have a Tesla Powerwall battery installed in his home in December 2015.

He saw it as a way to save on power bills and to ensure supply during outages.

"This home will go four or five days just with powering the refrigerator, the lights and the hot water system," he told the ABC.

"So it's worth the investment if you don't want that [a blackout] to happen to you.

"You need some roof space or some land without trees and some capital, maybe $10,000 or $15,000, the money you might spend on a pool or a new car."

Networks in most states and territories including South Australia are conducting battery trials to study the implications for their infrastructure.

As part of its trial, SA Power Networks can tap into customers' stored battery energy when needed to manage network issues.

Solar power users say the batteries allow them to save on bills and ensure supply during outages. ( ABC News: Kathryn Diss, file photo )

Energy Networks Australia (ENA) chief executive John Bradley said batteries were "absolutely" part of Australia's future.

He said the feedback from networks running battery trials was that the technology was performing well.

"The technology is performing in a predictable manner, the real art will be how we set the right incentives to get the full value out of it," he said.

He said the ENA's two-year study with the CSIRO also found customers could provide up to half the energy that is produced instead of conventional generators in the future.

"We could see up to 10 million participants in the market at this micro scale, all receiving incentives and payments for allowing their technology to support the grid, and that would mean that you had a much more efficient grid but a much more stable grid," Mr Bradley said.

But he said major market changes were needed before that could happen.

The ACT and Northern Territory, as well as the Adelaide City Council, are offering rebates for battery installations.