African Mining April 2020 | Page 42

savings that renewable solutions offer and include wind and solar into the power mix. As renewable microgrids develop in size and complexity, technology relentlessly advances, material costs drop, and hybrid solutions improve to ensure seamless integration of power sources and seamless reliability, renewables are becoming an inevitable part of mining power solutions. An average size off grid mine with a 30MW power plant will probably burn about USD1.4-billion of diesel fuel over a 20-year period, which is about one third of the total cost of the mine. In Australia, the mining industry has realised that renewable energy offers a cheaper, cleaner and smarter way to power their operations, and there is already significant interest in the use of renewables in the sector. The global mining industry consumes about 400TWh of electricity a year, posing a significant opportunity for hybrid renewables to be part of the energy mix. Stephen Hanson, COO of international renewables company juwi says that currently, just 0.1% of power supply on mining sites comes from wind and solar, with only 2240MW of wind and solar PV installed. “We are already starting to see mines transition to fully electric operations, as there are multiple benefits. The economics of a 100% renewable energy site are almost there, and with the introduction of hydrogen, we are almost certainly going to see 100% renewable energy-powered operations in the near future.” Manning says that the biggest benefit for mines employing renewables is cost reduction, and the ability to reduce their carbon footprint. “Another important related benefit is energy price certainty – with the inclusion of renewable in hybrid solutions, the mine is able to reduce its exposure to oil price or electricity price volatility,” says Manning. “We have developed a state-of-the-art integration system with our hybrid IQ solution that ensures a seamless power supply. At the core of the system is a micro-grid controller and SCADA system that incorporate all generation and distribution assets from wind, solar and battery to gas, diesel, heavy fuel oil and even hydrogen generators,” says Manning. "Manning says that the biggest benefit for mines employing renewables is cost reduction, and the ability to reduce their carbon footprint. The hybrid IQ system also includes enabling technologies such as cloud and wind forecasting which further optimises performance. Dave Manning, juwi’s global head of hybrid, says that in Australia there is already widespread consensus in mining that, a 50% renewable share at Australian mine sites should be considered the norm, and where possible 100% renewables should follow. “Mines are most interested in solutions that can reduce costs and carbon emissions,” says Manning. “The most advanced options to deliver this are hybrid systems that integrate solar, wind and batteries with diesel, gas or heavy fuel oil generators, without compromising reliability or power quality. Canadian mining company B2Gold’s solar farm in Namibia. 40  African Mining  April 2020 www. africanmining.co.za