More than 100,000 WA households could be entirely powered by their own solar energy using battery storage within five years under a 50 per cent tax rebate proposed by the Greens.

In one of first major election commitments by the party, Upper House candidate Tim Clifford said the cost of battery units were currently out of reach for a lot of people.

The Greens' proposed rebate would allow individuals to get up to half the cost of their storage system covered to a maximum of $5,000 in the first year and tapering off to $1,500 in five years.

The $290 million scheme would also provide a $5,000 upfront grant to install solar for families earning less than $80,000.

Households with solar panels in WA are looking to batteries as a way to offset the sharp fall in rebates Synergy pays them for their electricity.

It is hoped the scheme would kick-start the industry and drive down the cost of units and power bills.

Energy Minister Mike Nahan said a possible battery subsidy was discussed, but would not be implemented by the Government.

"We discussed it within the bureaucracy ... and it has been suggested by many participants in industry," he said.

"There is one in ACT now, I think it is $500 per household battery ... but the Government did not consider, or more importantly, is not going to implement a subsidy on batteries."

Dr Nahan said the decision not to progress discussions on the subsidy was not related to the Government's proposed sale of Western Power.

'It's pretty embarrassing': Greens candidate

But Mr Clifford said help was desperately needed.

"We are relying on last century's technology, basically," Mr Clifford said.

"We should be leading on this, WA is one of the ripest places in the world for battery storage uptake due to our high electricity prices ... and high solar radiation.

"[But] we don't have a renewable energy target and other states do. It's dismal and I think it's pretty embarrassing that we are behind other the states."

Mr Clifford said up to 3,000 WA businesses could also benefit, allowing their battery storage assets to be depreciated over three years rather than 15, which could pay off their battery storage unit within 10 years.

The scheme would be co-funded from the removal of federal fossil fuel and mining subsidies.

Greens supporter Rowena Skinner powers her home using solar panels but said she could not afford to install battery storage.

"For most people, the price is the issue, it is the main barrier," she said.