Energy use efficiency
Our results
In 2007, our energy efficiency improved 0.7 per cent compared to 2003. This has been driven by high production levels and improved utilisation of infrastructure through strong demand for our products, as well as the minimisation of unscheduled plant disruption.
But, industrial action at the Iron Ore Company of Canada during the cold winter months suppressed production at a time when energy use is at its peak. Our Pilbara iron ore mines saw increased fuel used for mining and increased demand for electricity supply to third parties in the region, which overshadowed other efficiency gains. Our Argyle diamond mine experienced a decrease in ore grade following its transition to underground operations combined with an increased reliance on on-site electricity generation that decreased its energy use efficiency. Coal operations on the east coast of Australia experienced rail and port restrictions while fuel and electricity continued to be used at the mines.
Performance against this target is challenging and we are now further away from our goal than we were last year. In 2006, we had achieved a 2.8 per cent improvement in energy use efficiency compared to 2003. Step changes in energy efficiency will not be possible within the target period. However, our executive committee has sponsored additional projects over and above "business as usual" to review and prioritise opportunities for large scale energy use savings and greenhouse gas emission reductions.
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We strive to improve the energy efficiency of all our operations. Some of the energy saving opportunities we have identified are actionable immediately; others require significant capital expenditure and have long design and construction lead times.
For example, we are currently developing a step change technology, the Drained Cathode Cell for aluminium production. This has the potential to significantly reduce the amount of process energy required to make aluminium metal.
A US$550 million pilot plant is being built at Rio Tinto Alcan's Complexe Jonquiere site in Canada to develop the proprietary Aluminium Pechiney Series 50 (AP50) smelting technology. The AP50 pilot plant is the initial step in creating up to 450,000 tonnes of new generation smelting capacity, based entirely on clean, renewable hydroelectricity. The technology offers lower carbon dioxide output and allows for emissions reductions that could be applied across the industry. The company has set an ambitious goal of developing an environmentally friendly aluminium smelting cell that is 20 per cent more energy efficient than existing technology.