Another 2000 to 3000 wind turbines would have to be built to meet Australia's mandatory renewable energy target of 20 per cent by 2020, says Jonathan Upson, senior development and government affairs manager with Infigen Energy.
These turbines would add 6000 to 7000 megawatts of electricity, which should mean no additional coal or gas-fired generators would be needed.
Although the medium-term prospects for wind generation were bright, the huge glut of large-scale renewable energy certificates made building new renewable energy generation uneconomic.
Infigen Energy, the largest wind farm owner in Australia, owns Capital Wind Farm, between Bungendore and Tarago, east of Canberra, which has 67 turbines.
The company has approval to almost double this. Only the present economics prevent the extension going ahead.
Mr Upson said about 20 new wind farms had been approved in Victoria and about six in NSW. These projects had been delayed by the ''small-scale screw up''.
That had now been fixed by separating the small-scale and large-scale schemes but the glut of certificates remained.
Mr Upson said some elements of the media spread a lot of misinformation about wind energy. Certainly, turbines killed a small number of birds, but this was infinitesimal compared to the number of birds killed by power lines, motor vehicles, cats and pesticides.
He also dismissed concerns that wind farms caused illness. ''There is no independent, regulatory, scientific or medical body in the world that thinks wind turbines make people sick.''
With wind energy worldwide doubling every three years, there would be an epidemic of biblical proportions if wind turbines made people sick. ''There are wind turbines everywhere in Europe and no one is getting sick.''
Mr Upson said the wind industry worldwide had grown by more than 25 per cent each year for the past 15 years. ''I challenge you to think of another industry that has had this sustained and long-term growth.''
Wind produced less than 2 per cent of the total electricity demand in NSW and the ACT, but in South Australia, with a greater wind resource and less demand for electricity, wind produced about 25 per cent of that state's total demand. At times, it reached about 70 per cent.
Though generation from wind turbines was variable, the Australian Energy Market Operator could now forecast wind energy throughout the grid with 98 per cent accuracy an hour ahead. This meant other generators were turned on or off as required.
Wind farms were expensive to build but were very cheap to run. So they could under bid coal and gas generators given suitable wind.
Infigen had plans to develop solar generation and would be pleased to be selected in the Solar Flagships program, he said. ''In which case we would build three large-scale solar facilities.''
One would be at the Capital Wind Farm, one at Nyngan and one at Manildra. At present, generating electricity from even large-scale solar plants was about twice as expensive as from wind.
''May be by the middle of the decade it might be more competitive … to build a large-scale solar facility we need some sort of grant or subsidy.''
Achieving 100 per cent of electricity from renewable sources was a terrific ambition but politically and practically that would be very difficult to achieve, he said.