The Greens will use the storage policy in its negotiations with the government over its budget,  Greens energy spokesman Adam Bandt said.

To support people adding batteries, the Greens want a 50 per cent refundable tax credit for individuals to pay for as much as half the cost of a new storage system. The payments would taper off from a maximum of $5000 to $1500 over the five years to 2021 in line with an expected drop of battery prices.

"Now is the time to jumpstart the battery industry, encourage the take up of storage and help make Australia a renewable energy leader," Mr Bandt said.

The nation's 1.4 million households with solar panels will be likely candidates to add batteries, especially as the price paid for exporting surplus electricity to the grid shrinks to a fraction of the retail price residents have to pay for power.

The Greens are hoping businesses will also take up the offer and will also direct the Australian Renewable Energy Agency (ARENA) to direct grants of as much as $5000 for households with less than $80,000 in annual taxable income to get batteries out to more families.

The policy has been costed by the Parliamentary Budget Office with the household policy totaling $2.85 billion and the business component $38 million over the forward estimates. The bulk of those funds will be paid for by removing the $2.75 billion accelerated depreciation permitted for aircraft and fossil-fuel intensive industries.

Mr Bandt said the battery plan would figure in talks with the Turnbull government over passage of its budget: "We'll be opposing most of this budget, which grows inequality and does nothing for clean energy, but if the government comes to us to talk about some of their less offensive measures, we'll want to talk to them about programs like this one."

John Grimes, chief executive of the Australian Energy Storage Council, said the cost of new batteries continues to tumble as new suppliers enter the market. On Wednesday, Chinas GCL group launched a 5.6 kilowatt-hour system for about $3000, wholesale.

Still, the Australian market remains "at a standing start", with only about 200 systems added a month and in need of a boost, Mr Grimes said.

Mr Grimes, though, predicted that more consumers will be crunching the numbers on batteries particularly as feed-in tariffs in states such as NSW tumble to zero from next year unless residents negotiate a  deal with their utility.

"People will say, 'blow that, I'd rather install a battery and use the power myself rather than give it away'," Mr Grimes said.

Increased battery use would have other benefits such as accelerating the closure of emissions-intensive coal-fired power plants. Flatter demand for grid power would also reduce the case for gas-fired peaker plants, Mr Bandt said.

ARENA's billion-dollar hole

Separately, Labor has come under more pressure for its decision to support the Coalition's billion-dollar cut from ARENA's grant funding, as reported by Fairfax Media.

The Abbott government stripped out $1.3 billion from ARENA in its 2014 budget and Labor last week committed to putting back just a tad over $300 million as part of its pre-election climate platform.

On Tuesday, Labor joined the Coalition to vote down a Senate motion by the Greens to restore the agency's full funding.

"It's incredibly disappointing that Labor has [on Tuesday] confirmed its climate policy is to lock in most of the Liberal Party's cuts to ARENA, leaving Australia with a $1 billion black hole in clean-energy funding," Greens Deputy Leader Larissa Waters said.