As a result of the energy problems confronting grid-tied mines in Africa, mining companies are increasingly considering developing and using renewable energy as a means to generate power.
Anglo American Platinum is stepping up its investigation of renewables now that South Africa’s main energy utility Eskom, is experiencing energy shortfalls. “This is a very big challenge for us,” says the company’s principal engineer for energy Gerhard van den Berg.
“With Eskom having shortages and not being able to supply, we’ve run into what they call stage-two load curtailment.”
To meet this curtailment, the mining giant has shed 65MW, or 10%, of its load by keeping the mines running but closing down some operations, including furnaces and processing plants.
“Renewables are the right thing to do because of the lack of capacity in the system at the moment,” says van den Berg.
Although the appetite for renewables among African mines first originated with remote sites that relied on expensive diesel generators for their power requirements, grid-tied mines are now keenly interested, as well, says Cronimet Mining Power Solutions senior project manager Gerhard Wernecke, who points out that the power crises in South Africa, Namibia, Botswana, Zambia and Mozambique are tipping the balance towards renewables in many African markets.
Reliability and price
For mines coping with unreliable energy utilities, finding ways to meet their companies’ energy needs is paramount, says Acacia Mining technical services general manager Nic Schoeman.
He says that Acacia’s biggest challenge at our mine sites is the extremely poor quality of power from TANESCO – the electric supply company wholly owned by the government of Tanzania.
Schoeman has commissioned studies on how renewables could help Acacia meet one of its mines’ 40 MW energy needs, and has even completed a tender and identified a forerunner among solar providers.
Similarly, Shanta Mining Company, which consumes 24 000 MW/h of energy each year, has installed a small pilot solar PV plant in order to assess the feasibility of undertaking a larger scale, hybrid scheme. Project director Ian Fielding points out that Shanta is also exploring the feasibility of hydro-electric power because the mine operates near a river.
Shanta’s Fielding points out that one of the greatest barriers to adoption of renewables is “obtaining an unbiased and comprehensive understanding of the real cost and suitability” of the various renewable energy solutions out there. Although there’s no shortage of “enthusiastic salesmen” with renewables schemes, sorting through the options is no easy feat.
What the future holds
Although a number of unknowns are affecting the outlook for renewables among African mines, many of these unknowns stem from the fact that renewables are relative newcomers to the market.
“One of the biggest obstacles is proving that the technologies are dependable and can save money and result in cleaner power, while meeting the same standards for reliability that these mines absolutely need,” says Primus Power business development and sales VP Richard Brody.
These issues, as well as others, will be discussed at the Renewables and Mining Summit and Exhibition to be held in Johannesburg on 1 and 2 July 2015.