The backbone of a future-proof portfolio

The new diesel-electric truck by Sandvik is a proof-of-concept vehicle designed to explore the possibilities of effectively combining electric systems and a diesel engine. Starting with a request from Australian customers in 2022, the fully developed product will be the first step towards electrification of mines where battery-electric or conventional electric vehicles are not an option.

“Not all customers are ready yet to introduce fully electric vehicles,” says Esa-Pekka Kantola, Product Line Manager, Load and Haul at Sandvik Mining and Rock Solutions. “This can be, for example, due to a lack of available charging capacity, but they still want to upgrade to the latest technology for lower TCO and improved performance together with better sustainability. The diesel-electric truck will be a solution for them.”

The demo truck has a conventional diesel engine powering two onboard generators to generate electric power for all the hub motors and other electric systems. Each wheel of the truck is driven by its own cooled hub motor.

The electric driveline offers several major benefits. Having no transmission or torque converter between the engine and wheels decreases the cost and workload of maintenance. It also reduces the number of potentially failing components, resulting in decreased downtime and a lower TCO.

The electric driveline allows for continuous, immediate torque from the start. This results in smoother starts, faster acceleration and a comfortable ride, as there are no gear changes.

The electric driveline also enables substantially longer component service life compared with a conventional mechanical power train. The benefits include lower TCO and longer overall service life, as well as the possibility of electric braking, traction control, continuous traction and adjustable speed limits, which can be programmed in the truck’s control system.

The electrically powered auxiliary equipment, especially the hydraulic powerpacks, are switched on and off as needed, eliminating all constantly running pumps coupled directly to the engine, which also improves energy efficiency.

Furthermore, the optimized rpm range of the engine is expected to save fuel and costs, and to reduce emissions. The money saved in fuel costs is obviously a welcome financial incentive for any mining company, while meeting sustainability requirements set by customers and governments is an increasingly important aspect as well. For further benefits that relate to fuel and emissions, it is worth noting that the diesel-electric truck can also, in addition to running on traditional fossil diesel, use paraffinic diesel fuels, which considerably reduces emissions during the equipment life cycle.

The purpose of the demo vehicle 
is to ensure that all the selected technologies work together as designed and can endure the harsh conditions 
in underground mines. The first round of testing was carried out in the Sandvik test mine in Tampere, Finland. The long-haul ramp test round was performed in the Callio FutureMINE 
in Pyhäjärvi, Finland. This former copper and zinc mine, one of the deepest in the world, offers excellent opportunities for testing in real world conditions, such as longer than average ramps.

“This platform shows the way forward for Sandvik underground trucks,” Kantola says. “According to 
our road map, while not forgetting the conventional diesel vehicles, we are now developing a truck platform to cover both diesel-electric and BEV options. There will also be a hybrid solution which takes the truck performance to the next level. This would mean a diesel-electric truck with a battery onboard.”