Power of green mines



Implementing green energy projects in Southern Africa, in particular the mining industry, was the subject of a seminar held at Wits University this month.

The first of its kind in South Africa, it was hosted by GX Energie, a German company specialising in the use of renewable energy.

“European, specifically German, energy companies have seen parallels between the way the demand for renewable energy has been developed in their countries and the demands developing in Africa,” said Professor Dick Minnitt, of the Wits School of Mining Engineering.

Germany has impressive models for green energy projects already in place. One village in Germany now produces nine times the energy it needs through green resources. It is a great inspiration to South Africans and shows what can be achieved by using green energy resources.

“Green energy entrepreneur”, Dr Michael Seeger, a director of GX Energie, said after the seminar that the South African mining industry was perfectly placed to lead the way in renewable energy. “The potential exists for mines, especially those involving green field developments, to reduce their demand for electricity and even take their facilities off the grid,” he said.

The primary source of this electricity would be solar power generated through photovoltaic power technology which converts sunlight directly into electrical energy. Photovoltaic power is the fastest-growing power-generation technology in the world and already generates electricity in more than 100 countries.

Within solar cells, positive and negative charges are separated by radiation energy and collected for use at the two poles of the solar cell in the same way as conventional batteries.

A typical plant would consist of ground-mounted solar panels, inverters, transformers and switchboards. A 10MW power installation would need a ground area of 150000 square metres, 44000 solar panels and related infrastructure. “These practical requirements make photovoltaic power ideal for mines which are usually situated on vast areas of land,” said Seeger.

Although costs would initially be high, Seeger suggests that the expense would be amortised over six years. “When the operational life of mines within South Africa are considered, the project becomes viable,” he said, adding that solar energy also offers opportunities for disadvantaged communities living near mines.

“If a mine were to cease operations after the cost of the solar plant has been amortised, it could be left behind as a sustainable project offering communities the opportunity to become power producers and onward sellers of electricity to the national grid.”

Seeger emphasised that when resources had come under pressure in Germany cooperation between the government and the private sector provided the key to realising alternative methods of generating electricity and that the country was reaping the benefits from bio mass, solar and hydro power.

“Although South Africa has vast coal resources, it is becoming increasingly expensive to move the commodity to power stations.

“Renewable energy allows plants to be erected where they are required, hugely reducing these logistics and long-term costs,” said Seeger. – With additional information from Judy Blom, business development manager at Wits University