An extra 41 turbines with blades up to 63 metres long could be installed in the area as part of Infigen's Capital Wind Farm 2 project.

Developer Infigen has lodged a modification request with NSW Planning and Environment to increase the length of the blades from 57 metres to 63 metres.

If approved they would be eight metres longer than Australia's largest blades, which belong to Victoria's Macarthur Wind Farm at 55 metres, and 19 metres longer than those at the nearby Capital Wind Farm 1 and Woodlawn Wind Farm.

The jump mirrors the growing size of turbines in Australia and across the globe as developers seek more cost-effective, energy-efficient solutions.

The total heights of proposed and completed wind turbines closer to home already top Canberra's Lovett Tower, the capital's largest building.

The technology's evolution in the capital region has been a beacon for developers amid a federal government review of the Renewable Energy Target.

But it's also divided politicians and residents with federal treasurer Joe Hockey dubbing farms in the Lake George area "utterly offensive" and a "blight on the landscape". A small number of residents have protested developments on their doorsteps amid fears of diving property values and daily disruption.

If successful, the Capital Wind Farm 2 modification leaves Infigen with the mammoth task of transporting the large blades to the area.

A similar delivery of blades to the Gullen Range Wind Farm near Bannister - a project that has hit a legal snag after a number of turbines were not built in approved locations - required the use of 56-metre trucks moving around modified corners under police escort.

General manager of development David Griffin said a similar truck with an extended trailer was expected to transport the blades about 200 kilometres from Woolongong.

He said the route would not require any major upgrades thanks to similar scale movements in recent years.

"We have done a very detailed analysis of every corner involved - nothing poses any particular problems getting those blade to the site," he said.

"It is quite an exercise in co-ordinating a lot of different stakeholders to get their approvals."

Despite the potential blade increase the overall height of the turbines will not increase, Mr Griffin said, with the tower remaining 94 metres tall.

"The size we're looking at is comparable with other wind farms in Australia," he said.

"Naturally with turbine technology, the blades have got larger over time with the objective of increasing their efficiency.

"Larger blades enable us to capture more energy."

Capital Wind Farm 2 would be an extension of Capital Wind Farm 1 and Woodlawn, which together have 90 turbines.

Infigen was among 18 wind companies vying for an ACT government 20-year deal to supply wind energy last month, which could see two or more successful projects make up the 200 megawatts that will be funded with a 20-year feed-in tariff. A decision is expected before the end of the year.

Clean Energy Council senior policy adviser Alicia Webb said wind energy was edging closer to becoming a real alternative to fossil fuels in Australia and around the world as the technology's efficiency grew and prices fell.

While the 63-metre blades might fall short of the world's largest - a mammoth 80 metres in Denmark - Ms Webb said the blades were quite large by Australian standards.

On a global scale, Australia was comparable with onshore wind farms in other countries such as the UK.

"A developer can get greater efficiency and in some cases use less turbines to make the same amount of power by putting in a bigger model," she said.

"At the moment we have towers around the 80-metre mark or in some cases 85 or 90 metres off the ground. When I started working in this industry 10 years ago towers were 60 or 65 metres off the ground."

Ms Webb said developers needed to look ahead of evolving technology when determining maximum heights and lengths during the approvals process, which could bump up proposed blade sizes.

"Depending on how long it is between a project getting development approval and actually signing the contracts and being built, sometimes technology has moved on in that time. The technology is always changing and getting more efficient and cheaper."