Electric vehicles are increasingly seen by mining operators as an effective way to not only slash a facility’s carbon footprint, but to also improve site safety.
For one thing, they have zero local emissions. This makes a big difference to air quality underground, as electric vehicles do not emit any of the harmful gases and particulates that come from diesel engines such as nitrogen oxide.
Long-term exposure to nitrogen oxide can cause breathing difficulties, resulting in conditions such as lung inflammation and asthma. Short-term exposure has been found to cause headaches and eye irritation, which could limit the effectiveness of workers.
Underground environments can intensify these effects, as the airflow is more restricted and oxygen levels can fluctuate. Breathing equipment can be a solution, but if there are no harmful emissions in the first place then the need for its widespread use is reduced.
Electric vehicles offer a tried and trusted solution to improving underground air quality. And it is important to remember that a healthy workforce is a more productive one.
Another improvement on diesel engines is that electric vehicles are able to travel faster underground thanks to increased torque and handling. Electric vehicles emit less heat, with minimal risk of the engine overheating and causing hot surfaces on equipment
Normet’s electric vehicle fleet, for example, has been specifically developed for use in the adverse conditions encountered in underground mines.
They produce lower levels of noise, improving safety further by allowing workers to better communicate with each other and have fewer distractions.
Exposure to vibrations over lengthy periods can cause stresses for structures and compromise their integrity. This is a factor that needs to be monitored especially when operating hundreds of metres underground. As electric vehicles produce substantially less vibrations than petrol or diesel engines, this almost completely nullifies this structural threat.
Vibrations are a contributing factor to wear and tear in vehicles, so their relative absence from electric engines is one of many factors that contributes to maintenance being minimised for EVs.
One of the biggest questions customers have with EVs relates to the battery life. As the investment is higher for EVs, the lifetime expectation can be a concern to customers. To address this issue, Normet is exploring options such as rental and leasing models, i.e. Battery as a Service.
This then lowers the technological and financial risks related to batteries for the customer and could remove a hurdle in getting this technology operating in the field.
Normet is confident that once customers see the technology in action during operations, their concerns will be alleviated and they will witness just how effective the technology is.
The Normet SmartDrive BEV model features the very latest in technology for lithium-ion batteries. The battery is divided into separate modules, meaning that if one unit is not working as it should then operations can continue uninterrupted. Alongside this, there is a much lower chance of the vehicle breaking down.
Utilising rapid charge, the batteries can get an 80% charge in half an hour through the onboard system. Charging can take place during other times as well, both when the vehicles are travelling downhill thanks to the onboard regenerative braking functionality, and when the machine is connected to electrics, for example, during concrete spraying.
There are two versions of Normet SmartDrive CC150 and CC300 all-in-one charger cabinets, either 150kW or 300kW DC. They can be installed wherever they are needed on-site, either underground or at the surface level.
Normet’s SmartDrive fleet contains seven vehicles, which have all been designed to cover the extensive range of operational requirements for the mining industry whilst helping to boost safety.
For example, Multimec is Normet’s equivalent of a mining utility vehicle. It can be used for several tasks in mining operations such as transporting materials and workers, along with maintenance duties and vehicle fuelling. While the Utilift MF 540 SD is a fully electric scissor lifter that can be used for underground installation activities and is capable of lifting loads of 4.5t.
Alongside electric vehicles, Normet’s technology has also been found to improve the safety of underground explosives. In June, Normet became the first company ever to carry out subsurface drift round charging using an electric solution. Tests took place at First Quantum Minerals’ Pyhäsalmi mine in Finland.
The Charmec MC 605 VE SD eliminates the need to connect with a mine’s electricity mains supply, improving the safety and efficiency of explosives charging, while at the same time increasing its control and precision.