The ACT government has boosted its commitment to renewable energy still further, announcing Canberra will be fully powered by renewables in four years.
The 100 per cent renewable target will add $290 to the average electricity bill at its peak in 2020.
Just last year, the government announced a target of 100 per cent renewable energy by 2025, but on Friday Environment Minister Simon Corbell will bring that target forward by five years, to 2020.
To get there, he is boosting the current renewables auction from 109 megawatts to 200MW, with bids due on May 13.
Labor's switch to renewable energy began with the decision in 2013 to fund three solar farms. Since then, it has held two wind auctions and signed contracts with four companies to buy energy from wind farms in South Australia, Victoria and NSW.
The government is signing 20-year deals, offering a guaranteed payment to the renewable projects for the energy they feed into the national grid.
The cheapest price to date is the $77 a megawatt hour it has agreed to pay to a French-owned wind farm at Hornsdale in South Australia.
The solar projects, all in and near Canberra, are more than twice as expensive.
In all, the wind and solar projects have 640MW of capacity, which is equivalent to 76 per cent of Canberra's energy use.
Because the clean energy costs more than coal-fired power, Mr Corbell said the move to renewables would add $290 a year to the average electricity bill at its peak in 2020, before declining. The average electricity bill is about $1500 a year at the moment.
The costs would be largely offset by savings that households are making through programs including the free replacement of downlights, adding to an average $260 a household per year.
Mr Corbell said Canberra was leading the nation on renewables, and reaping the benefits.
Companies bidding for government energy contracts must promise investment in Canberra as part of the deal, and Mr Corbell said the projects had so far secured $400 million in local investment.
Although the projects are almost entirely interstate, companies are funding tertiary courses in renewable research and to train workers for the renewable industry, and setting up headquarters and maintenance bases in Canberra.
Mr Corbell said taking the extra step to 100 per cent allowed Canberra to "take advantage of favourable market conditions to lock in great long-term prices", with renewable companies keen to secure long-term contracts.
"Adding an extra 91MW of renewables to our current auction process will allow us to take advantage of the record low prices and significant local investment we have achieved in our recent auctions," Mr Corbell said.
To date, the government has signed contracts for:
Only the Royalla solar farm near Tuggeranong and the Coonooer Bridge wind farm near Bendigo are operating.
Other contributions to the target are the ACT's share of the national renewable energy target (20 per cent of the total), rooftop solar (3 per cent) and Green Power (1 per cent).
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