Modern Mining June 2018

POWER SUPPLY AND ENERGY EFFICIENCY

more reliable solution compared to the grid.” According to Schön, juwi can design hybrid plants that can produce electricity below 10 US cents per kWh in many locations in Africa. Reliable and robust integration of solar or wind into diesel or HFO power stations at mines is a key success factor. Therefore juwi has developed hybrid technology and solutions that enable seamless integration of various power sources. Manning explains: “What we call the hybrid controller is the heart of the operation and designing and implementing it properly is of paramount importance. Juwi has put a lot of engineering and development into that pro- cess, ensuring that all sources in the power system work seamlessly and balance solar, diesel, wind or battery so that there is zero interruption to supply. It is all about maintain- ing voltage, frequency and power factor no matter if the sun shines, the wind blows or a large mill ramps up.” Juwi has developed a SCADA that seam- lessly integrates the components of hybrid renewable energy solutions. “What we found is that other systems provide only separated

views or systems; one for solar, one for diesel and maybe wind and battery, but not integrated properly and with high resolution,” states Manning. “What the juwi hybrid SCADA does is bring it all together into one system that monitors and combines everything and gives the operator easy access.” The juwi Group was established in 1996 in Germany. juwi Renewable Energies based in Cape Town (juwi South Africa) is participating in the Renewable Energy IPP (REIPP) Procurement Programme initiated by the South African gov- ernment for utility-scale renewable energy power generation. To date, juwi South Africa has built five solar plants totalling 121 MW under the REIPP Procurement Programme. 

Solar panels at the Mulilo Sonnedix Prieska PV solar park in South Africa’s Northern Cape Province – engineering, procurement and construction by juwi.

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June 2018  MODERN MINING  33