The WA Greens have named a renewable energy advocate as their candidate for the Canning by-election.

Vanessa Rauland, a small business owner and a lecturer at Curtin University, will run in the September 19 federal by-election brought on by the sudden death of Liberal MP Don Randall last month.

Ms Rauland said it was important to give voters a Green option.

"We know it could be a long shot to win this by-election, but we're always trying to push up the vote and allow people to have the the option to vote Greens," she said.

"We've seen it in Melbourne recently, the Greens took a seat from the Liberals there.

"Right across the board, Labor and Liberal have failed our community, from climate change to equal marriage to data retention."

Ms Rauland said she would focus her campaign around renewable energy, arts and education issues.

"Considering almost 50 per cent of the householders in Canning have some form of solar, whether its PVs or solar hot water on their roof, they're clearly in favour of renewable energy," she said.

"I'm going to be campaigning very strongly for renewable energy, particularly for the solar industry."

The major parties last week endorsed their candidates for the by-election.

Former SASR (Special Air Services Regiment) officer Andrew Hastie will stand as the Liberal Party candidate, while former Law Society of WA president Matthew Keogh will run for Labor.

Clive Palmer's Palmer United Party has announced Vimal Sharma, the managing director at Mr Palmer's Mineralogy resources company, as its candidate.