Energy use

At our operations, we both consume and produce energy. Our mining and mineral processing operations are energy intensive activities that depend heavily on electricity, coal, oil, diesel and gas to keep them running. At the same time, we are one of the world's leading producers of coal and of uranium for the nuclear power industry. 

More than half of our energy is used to add value to the ore we produce. The remainder is used in mining and transport. We generate our own electricity and we purchase electricity. Beneficiation usually requires significant energy inputs to produce useful products for consumers.

So it makes good business sense to improve the energy efficiency and reduce costs at our operations.

How we save energy

We act on many of the energy saving opportunities that we identify. But some improvements require significant capital expenditure and have long design and construction lead times.  We also invest large sums in research and development with the aim of developing more energy efficient processes.

We have instituted a comprehensive programme of energy audits at our operations to identify a range of energy saving opportunities, and several of these have already been successfully implemented. And as a leading international coal supplier, we are helping to develop technology for carbon capture and storage worldwide.

In addition, we are a significant supplier of uranium oxide for the world's nuclear industry, which is a low emitter of greenhouse gases. So we are currently developing  processes for product stewardship and, with other uranium producers, have formed a group to look at the implications of the entire fuel cycle.

Our target is to improve energy efficiency by five per cent over a five year period. In essence, we aim to reduce the energy use per tonne of product over the period 2003 to 2008 by five percent.

Our results

Total energy use

The total amount of energy we used increased 5.0 per cent to 258PJ in 2006.

The increase is primarily due to increased production at two recent developments, Yarwun (alumina refinery) and HIsmelt® (pig iron smelter) and increased production at a number of businesses, including Rio Tinto Iron & Titanium and Pilbara Iron

Over the past five year, there has been a 15 per cent increase in energy use from operational expansions and new developments.

Energy efficiency

We are half way to our target of five per cent improvement in efficiency. In 2006, our energy use efficiency improved 2.6 per cent compared to 2003. This a positive result, but there has been a small dip since 2005.

Our performance was affected by a planned maintenance shutdown at Kennecott Utah Copper, where reduced production of refined copper, combined with high concentrate production and on-going mining, resulted in higher energy use per tonne of copper produced. 

However, despite the decline in performance during 2006. there has been an overall improvement across the group since 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.

Sources of energy

Sources of energy we used in 2006 - and indirectly by others to produce the electricity and steam purchased by us - are compared with the worldwide use of primary energy sources as reported by the International Energy Agency (IEA). Our inventory includes a significantly greater proportion of hydroelectric based primary energy than the international average, almost nine per cent compared to a component of around two per cent worldwide (2004 data).