Ventilation and the electrification of underground mining
BBE’s Russell Hattingh sees growing interest in using electric vehicles (EVs) in future underground mining: to meet increasingly stringent emissions requirements, improve efficiency and reduce ventilation demand. In this article, he highlights the need to thoroughly evaluate the benefits and consequences of transitioning to EV use.
“A cross the mining industry, the transition to electric vehicles (EVs) is becoming increasingly topical. While we are seeing growing interest on South African roads, there is similar interest towards EVs for underground mining, with trucks and load-haul dumpers (LHDs) being particularly interesting candidates to switch to electric drives,” begins Russell Hattingh. “Interest in replacing diesel-powered equipment is driven largely by the potential health and cost benefits. With the increasing mechanisation of mining operations, the use of diesel-powered equipment has continued to grow. While diesel fleets offer many opera - tional advantages, the products of combustion emitted from the exhaust present significant challenges. Diesel exhaust gases and diesel particulates, formed through the incomplete combustion of diesel fuel and commonly re- ferred to as diesel particulate matter (DPM), pose a substantial health risk. Exposure to these emissions can result in overexposure to toxic gases and carcinogenic particulates, with long-term health implications.” “Traditionally, exhaust gas fumes and particulates have been managed through dilu- tion ventilation by increasing the air volumes supplied to the mine,” he explains. To meet ever-tightening legislative re- quirements, underground miners using diesel
engines must invest in cleaner vehicles with higher Tier emission ratings and install diesel particulate filters (DPF) to keep combustion products out of the ventilation stream. They also now need to use higher-quality diesel with lower sulphur levels. “This shift is already happening, because mining companies care about the safety and long-term health of their workers,” says Hattingh. “The bigger and more mechanised the operation becomes, the more mining owners need to care because, ultimately, it becomes material. Not only does it affect the health and productivity of underground miners, but it also requires more surface ventilation to handle dirtier air. If not captured or treated at the source, contaminants released into the mine ventilation system cannot be easily removed from the underground air stream. Instead, they must be diluted and exhausted from the mine, and the only way to do that is to increase ventilation levels,” he explains. “More air means more shafts and tun- nels and more fans. As more electricity is consumed, operational costs also increase, making the dilution approach an expensive solution for eliminating emissions. So the obvious first solution to look at is to improve the engines used underground, so they con- sume less fuel and produce less exhaust gas,” he argues. On transitioning to EVs, he says that a fleet
of underground mining machines is not a con- sumable that can easily be swapped out for a better option, though. “Investments typically target a 7 to 10-year life or, in lower-cost op- erations, longer. So long-term planning has to come into play when considering any switch, be it to more fuel and emissions-efficient en - gine options or phasing out all diesel vehicles as part of a long-term migration towards full electrification,” he tells MCA . Challenges to electrification Replacing an underground diesel fleet with electric vehicles is not a silver-bullet solution, Hattingh continues. “Electrification has its own issues. First off, an electric truck or LHD is still more expensive than a diesel equiva- lent. In addition, EVs need to be charged, so the charging infrastructure has to be carefully planned. You cannot bring these vehicles to the surface every evening to recharge them,
Left: Contaminants released into the mine ventilation system must be diluted and exhausted from the mine, and the only way to do that is to increase ventilation levels. Right: While EVs can reduce refrigeration demand compared with diesel fleets, the reduction is constrained by minimum air-velocity requirements, and the overall benefit depends strongly on the mining method.
32 ¦ MechChem Africa • May-June 2026
Made with FlippingBook flipbook maker