Combating the risks of climate change

Rio Tinto Aluminium is ramping up efforts to manage its global emissions of greenhouse gases (GHGs) by implementing a portfolio of initiatives. Its climate change strategy includes improving energy efficiency at its operations and working with stakeholders to explore innovative solutions to this global issue.

Making primary aluminium is resource and energy intensive, and mining, refining and smelting operations produce large quantities of GHGs. Most of these are attributable to the smelting process, which is a heavy consumer of electricity. In 2006, Rio Tinto Aluminium produced about 12 million tonnes of carbon dioxide equivalent from its global operations. However, since 1990, dramatic reductions in emissions have been achieved across all the group's smelting operations. Of particular note, perfluorocarbon emissions have been reduced by a net 86 per cent and by more than 91 per cent per tonne of product.

"The problem we face, along with all producers, is that we have already made significant reductions in emissions," says Rio Tinto Aluminium's climate change manager, Rick Humphries. "So the opportunities for making further cuts in the smelting process are limited - unless there is a breakthrough in the technology. Not only that, because we now produce more aluminium, our total emissions have naturally increased too. But at all our sites we are looking for innovative ways of cutting our emissions of GHGs. Reducing total emissions is the big challenge."

One of the most unusual climate change initiatives at Rio Tinto Aluminium is the Minding the Carbon Store project. In 2004, the Queensland State Government in Australia legislated to control the large scale clearing of native vegetation. A company called The Carbon Pool purchased clearing permits from landowners and undertook to protect the resulting uncleared vegetation for 120 years.

Rio Tinto Aluminium was the first company to buy into the scheme, purchasing up to one million tonnes of verified greenhouse gas abatements. The scheme has won praise from federal and state governments, agricultural associations and environmental organisations.

"If we can use offsets as one component of an emissions reduction strategy, then we will make a big difference and perhaps set precedents for other minerals and processing industries," Rick Humphries enthuses.

Another key focus for Rio Tinto Aluminium is research. Rio Tinto Aluminium Technology, a dedicated technical research and support unit operated within the product group, has been working with university partners to develop a technology called drained cathode cell smelting. One way to cut the energy used to produce aluminium is to reduce the distance between the anode and cathode in the electrolytic cell, thereby lowering the electrical resistance of the electrolyte, which in turn means less energy is used.

The new technology has the potential to achieve energy savings of ten to 15 per cent of the electricity now used at Rio Tinto Aluminium's smelters. A demonstration project of drained cathode cell technology is under way at the Bell Bay smelter in Tasmania.

Another important aspect of Rio Tinto Aluminium's climate change strategy involves working in partnership with key stakeholders. Over the last year, Rio Tinto Aluminium has collaborated with The Great Barrier Reef Foundation on the Future Reef partnership. The partnership, through The University of Queensland, is conducting the world's first study of the effect of ocean acidification on Queensland's Great Barrier Reef. As part of this four year partnership, more than 100 Rio Tinto employees will travel to the Heron Island research station located off Gladstone, Queensland, to help collect and analyse data.

Another partnership is with the Energy Efficiency Conservation Authority and the Te Runaka o Awarua Charitable Trust in New Zealand. The project, called Bluff Healthy Homes, involves retrofitting homes with energy efficient products in the town of Bluff near the Rio Tinto Aluminium managed New Zealand Aluminium Smelters in Southland.

Rick Humphries says that implementation of Rio Tinto Aluminium's strategy to combat emissions is progressing well but that more work needs to be done: "We know what our carbon footprint is and are focused on implementing long term measures to achieve significant cuts. We still have some way to go but we have established ourselves as a serious player in one of the most important global issues facing society today."