Unlikely bedfellows: mines that run on solar or wind power

Over in Tanzania, African Barrick Gold is exploring the possibility of using solar power at its Bulyanhulu mine, Mining Weekly reports. The company has also looked to move away from diesel-generated power by tapping into the state-run power utility, which uses a combination of hydro, natural gas and thermal energy. African Barrick Gold expects solar could give its three mines in Tanzania 18 percent of their power needs.

And then there's wind

Wind power is also being tried by mining companies intent on slashing electricity bills. Vale, the world's third largest mining company by market value, has formed a joint venture with Australian company Pacific Hydro to build and operate two wind farms in Brazil's northeast.

Vale, a major iron ore producer, is expecting its demand for electricity to jump 150 percent by 2020. In a press release, the Brazil-based company said it wants to use hydro, wind and biomass to help meet that demand, as well as to diversity its energy mix, reduce emissions and cut costs.

As mining companies continue to evaluate their power options in an era of higher diesel fuel and electricity costs, it is interesting to contemplate whether they could one day foresee operating in an environment more weighted towards renewables than conventional energy. While that seems far-fetched now, considering the amount of equipment and plant machinery that relies on conventional power and fuel, the examples cited here show that renewables are already finding increasing currency among the world's major miners.

They also demonstrate that mining companies are not oblivious to broader environmental issues, and are willing to make changes in the direction of renewables, especially if there is a motivation to cut costs.