When it comes to energy management, mining faces a unique challenge; over the life of a mine, energy use typically increases. Take, for example, a typical copper mine.
The Energy Challenge
As the copper resource is developed, mining begins by extracting ore closest to the surface. As these resources are removed, equipment must mine ore from an increasing depth. Deeper pits result in longer, uphill hauls for trucks to deliver ore to the mill for processing — increasing diesel consumption, which results in greater energy consumption and GHG emissions.
In addition, to enhance project economics, higher grade ore is commonly processed early in the mine life, followed by lower grade ore. Our Highland Valley Copper Operations were processing ore with a copper grade of 0.47% in 1988; this had declined to a grade of 0.30% in 2012. Decreasing ore grades mean that greater amounts of material must be moved and processed to achieve the same quantity of final product.
This combination of increased haul distances and decreasing ore grades increases energy consumption and GHG emissions required to produce each tonne of product over the life of a mine.
What is Teck Doing?
While an operation’s energy profile will typically demonstrate increased energy consumption over time, we are nonetheless committed to minimizing the impact of increasing energy consumption and GHG emissions. Our energy goals focus on pursuing projects that enhance energy efficiency and thereby reduce GHG emissions at any stage in a mine’s life. This is also a part of our longer term strategy with our 2030 energy and GHG reduction targets. One example of a short-term energy goal is our investment in the Wintering Hills Wind Power Facility near Drumheller, Alberta, which has contributed significantly to our target of achieving 30 megawatts of alternative energy generation by 2015.
In the future, it is likely that new resource development projects will be in even more remote locations, perhaps with lower grade material that is more challenging to extract and process. These factors all suggest that mining is likely to become even more energy intensive. This will make it challenging to reduce our energy intensity and the associated GHG emissions. With this understanding in mind, we are developing goals around the design of our new projects to ensure that we are continually evaluating best practices for future operations.
First Published on June 30, 2013