Labor's current target is 90 per cent renewables by 2020 and to get there, it is buying power from five or six wind farms, three solar farms within the territory borders, and a big-dish-style solar project whose details have yet to be settled.

Mr Barr will tell 327 delegates at the party's conference that the 100 per cent target is achievable, putting the ACT at the global forefront in its response to climate change.

"We can do this. We have shown it's possible – now we have one small step left," he said. "Canberra can and should be a beacon for everyone who realises the world must act decisively now to stave off a future of catastrophic climate change."

The government is buying the bulk of its renewable energy through auctions, where companies compete for 20 year contracts at a guaranteed price. One solar farm began operation last year, with a second being built and a third in planning. The first three wind farms have begun or are preparing to begin construction, between them producing sufficient energy for one-quarter of Canberra's needs. And the government has called bids for its second wind auction this month.

Environment Minister Simon Corbell has said the initiatives to date, including the new auction, would bring the city close to its 90 per cent target. The renewables will add an average $240 a year to the average electricity bill for Canberra households by 2020, he has said.

The government is yet to announce details of how it will fill the final 10 per cent of the target, but it has the advantage of being able to move to renewable energy without threatening any other energy-generating industries, a factor that makes it more difficult for states like NSW to go nearly so far.

Canberra has also taken advantage of the uncertainty surrounding renewable energy nationally, which has left wind farms and others in limbo, desperate to win a funding stream such as that offered in Canberra - and willing to bid low prices to win.

Mr Corbell has given the nod to wind projects in Victoria and South Australia, avoiding the angst of upset farming communities, but has ensured the ACT gets economic benefits by choosing companies that have promised to set up headquarters, operations hubs and academic courses here. He wants Canberra to become a centre for renewables research, and for training maintenance and other wind and solar workforces.

Mr Barr said Canberra had already seen a 400 per cent increase in renewable energy jobs in the past five years – he did not give specific figures, and the 100 per cent target would drive still more growth in research and corporate jobs.

He would also continue to divest the ACT investment portfolio of high-carbon emitting companies and sectors.

Mr Barr enters today's conference as Labor is deep in preselection negotiations. One minister, Simon Corbell, has already fallen prey to disillusionment among parts of his left faction, with persistent rumours that he was seeking preselection but was rebuffed with a poor vote from his faction, with the result that he announced he will not stand for election next year.

Another minister, Mary Porter, is said by party members to be facing a challenge from right faction colleague Tara Cheyne for a spot on the ballot paper in Belconnen, but Ms Cheyne has not confirmed her candidacy, nor returned calls.

Among debates today, the Transport Workers Union will push back on the entry of the taxi-alternative Uber into Canberra, putting a motion aimed at ensuring protection for taxi drivers as well as Uber drivers.