Funds employing carbon-efficient investment strategies have the best chance of maintaining returns and portfolio diversification, according to a report by environmental research company Trucost.

 "When a price for carbon is established in Australia... the winners will be those companies which are more carbon or energy efficient," Trucost chief executive Simon Thomas said at the launch of the research report, at the recent Australian Institute of Superannuation Trustees (AIST) Conference.

The report titled "Carbon Counts 2008: The Carbon Footprints of Australian Investment Managers" measured the carbon footprints of 14 of Australia's largest superannuation funds.

The AIST-commissioned research revealed there was a 36 per cent difference between the largest and smallest footprints of the funds.

Sustainability and Growth portfolios were the most carbon efficient, while Enhanced Index portfolios had the greatest carbon intensity.

According to Thomas, funds that adopt a carbon optimisation strategy could significantly reduce their carbon footprint, without sacrificing returns or stock diversification.

At the launch, AIST chief executive Fiona Reynolds said superannuation funds need to manage long-term risk and that climate change was one of the greatest long-term risks of all.

"While it is still early days in the brave new world of carbon-pricing, this research suggests... there may be just as many investment opportunities as there are risks, particularly for those that get on the front foot of the issue," Reynolds said.