In recent years, global use of renewable energy has increased rapidly. According to an annual global renewable status report published by the Renewable Energy Policy Network, global renewable electricity production increased from 800 gigawatts to 1,560 gigawatts.
Despite these gains, only 20% of global energy is generated using renewable resources such as biomass, solar, hydroelectric, and geothermal. Right now, the economics of renewable energy sources combined with an abundance of cheap fossil fuels are preventing renewables from competing in many markets.
However, in some industries, renewables are already outcompeting conventional sources of energy. Perhaps surprisingly, the mining industry is one of the most likely places for the near-term proliferation of renewable energy sources. TH Energy, a large energy consulting company, is so convinced that renewables are the way of the future at some mining sites that they’ve put together a database containing information on companies that are already using renewables at remote mine sites. Their website also provides information about the relative costs of different energy generating technologies.
To better understand why renewables are more competitive at remote mine sites, let’s take a look at Rio Tinto’s Diavik diamond mine. The mine is located on a remote island in Canada’s Northwest Territories, about 300 kilometers from the nearest town. According to the mine’s business improvement manager, 60-70 million litres of diesel fuel are trucked to the island each year during the winter months. Of course, transporting the diesel requires more diesel, and the commodity doesn’t come cheap so far from major refineries.
Although Diavik is especially remote, many mines are located far from the nearest electricity grid. The cost of transporting fossil fuels to these locations begins to make renewable energy more competitive.
Despite the cost benefits of using wind or solar energy at mine sites, there are several technical issues to overcome. The first isn’t unique to mining sites – renewable energy sources just don’t provide the same consistency as traditional sources. Unlike most electricity grids, in which fossil energy production can be increased by bringing extra capacity online when renewable production fluctuates, a remote mine needs to be self sufficient. Mining operations are expensive and complex to shut down in the event of an energy shortage. This fact will limit the proportion of energy generated by renewables at each mine until we come up with a cost effective way to store the energy and release it at a constant rate.
A second problem is that mining sites are sometimes short-lived compared to some industrial installations. Unlike diesel generators, which are portable, renewable resources often involve a significant investment for installation. One solution to this problem is simply to develop portable versions of these energy sources.
It will be interesting to see how the relationship between mining and renewable energy plays out in the near future.