TORONTO (miningweekly.com) – Mining companies these days are considering implementing various renewable power projects at mine sites mainly to reduce greenhouse-gas (GHG) emissions, to demonstrate sustainability and to drive down costs, a representative from the world’s biggest gold miner, Barrick Gold, told the Renewable Energy and Mining Conference in Toronto on Wednesday.
The company’s director of power within the projects division, Scott Fraser, said Barrick’s attraction to renewable power sources was not initially for cost savings, but more altruistic in nature.
It was only in recent years that the cost benefits became apparent. For example, the significantly reduced risk and costs of diesel fuel transport to its remote operations, especially in South America, the reduced emissions and the shelter from oil price volatility had resulted in an increasing awareness within the company that renewable power sources were increasingly becoming business propositions.
Barrick had invested in wind projects in Chile and Argentina, including the 20 MW Punta Colorada wind farm that was intended to support the halted giant Pascua-Lama project.
Fraser pointed out that today, mines are often dealing with lower ore grades, which resulted in increased power needs as more work needs to be done to extract the same amount for payable output, which was creating an opportunity for renewable power sources to play a critical role in reducing energy costs.
He said Barrick’s focus was on energy conservation alongside renewable power sources. He said several of the company’s operations were located off grid and some were connected to unreliable grids, which drove the company’s reliance on diesel-fired generation.
However, increasingly, the company was looking to augment these operations with renewable options to save on costs and for the additional GHG emissions reductions.
“Chile has seen our greatest investment in renewables, which is partly driven by the government’s renewable-energy requirement. When you use electricity in Chile, you either have to have a certain portion coming from renewable-energy sources, or you are required to buy renewable-energy credits from within the country, at prices that are expected to increase in the future,” he said.
Barrick currently has two demonstration sites for solar power. These included 1 MW of installed power in Reno, Nevada, where the company had been in discussions with solar developers interested in using the legacy mine site to develop a solar farm. The company also has a small test solar farm in Chile.
Fraser said that Barrick was also investigating other sources of renewable energy at its operations, including regenerative braking on downhill conveyors, while it was also looking at about 20 mine sites around the globe that could potentially offer pumped storage opportunities. The company was also studying geothermal options at three mine sites.
“One of the largest barriers is the intermittent nature of renewable-energy sources. This requires an alternate power supply or a national grid backup, because mining normally has a very continuous demand,” he said.
He added that while power storage technologies were continuing to develop, the life cycle cost of energy storage remained prohibitive for most industrial applications.
Diversified Canadian miner Teck Resources had also committed to lift its alternative-energy generation to 30 MW by 2015, and to 100 MW by 2030 as part of the company’s sustainability strategy.
Energy leader Terry Brace told the conference that Teck was already well on its way to reach its renewable-energy goals by owning two-thirds of the Waneta dam hydroelectric project in British Columbia, and also being a partner with oil sands miner Suncor, in the Wintering Hills wind power farm, in Alberta, which currently adds about 10 MW to the company’s goals.
Meanwhile, Namibia-born Rio Tinto business improvement manager for Diavik Diamond Mines, Liezl van Wyk, said existing projects often needed a ‘dot connector’ to push renewable power projects through, as was the case at Diavik, in the Northwest Territories, where the company had installed about 9.2 MW of wind-power generation capacity in 2012.
Van Wyk said that while the main drivers for implementing the project were site specific, including the extreme, remote location, the 2008 global financial crisis had also focused the company’s awareness on implementing renewable energy to achieve cost reductions.
The wind farm, which began delivering power to the mine's grid in September 2012, was expected to lower the mine's yearly power-related diesel fuel requirement by 10% and reduce its carbon footprint by 6%. It would also reduce Diavik's seasonal winter road fuel haul by about 100 loads.
Another company with renewable energy on its mind is exploration and development junior Sandspring Resources, which is developing the multimillion-ounce Toroparu gold/copper deposit toward potential large-scale production in 2015.
President and COO Yani Roditis said that while the company was pushing ahead with development of its flagship project, it had signed a memorandum of understanding with the Guyana government to construct the Kurupung river hydroelectric project, which would provide the mining operation with all of its electricity needs.
He said the 60 MW private generator, located 60 km from Toroparu, would support development of the Cuyuni-Mazaruni mining district.
“The hydropower project will make our mining project more financeable, while Sandspring will leave a positive legacy in place long after the mine had closed,” he said.