Over the course of a 10-week project in late 2018 at Skanska’s Vikan Kross quarry, near Gothenburg, Sweden, Volvo Construction Equipment (Volvo CE) tested the viability of a project it refers to as ‘electric site’, a research initiative to test replacing the machines deployed in a quarry with electrified equivalents.

This included: a 70-tonne, EX1 cable-fed electric excavator prototype to load the primary crusher at the quarry; an LX1 prototype electric hybrid wheel loader, which yielded a more than 50 per cent improvement in fuel efficiency as well as a large noise reduction, to organise the material at the site; and eight HX2 autonomous, battery-electric haulers to transport the material from the primary mobile crusher up to the secondary static crusher.

Cost savings

The project resulted in a 98 per cent reduction in carbon emissions, a 70 per cent reduction in energy cost and a 40 per cent reduction in operator costs.

“The results we have seen so far confirm that this research project is a step towards transforming the quarry and aggregates industry and creating emission-free quarries,” noted Uwe Müller, chief project manager for the electric site, pointing to the project’s environmental, efficiency and safety benefits.

The findings support the potential for a 25 per cent reduction in total cost of operations based on projections for the impact of the results of the pilot if applied to a full-scale commercial application.

“Testing prototype machines with a customer at an early stage in the process speeds up development and brings more value to us and our customers,” said Melker Jernberg, president of Volvo CE.

Alongside electrification, the LX1 and HX2 designs also incorporate more fundamental changes. On the LX1, the central driveline has been replaced by four electric drive motors mounted at the wheels, while the lifting power is provided by electric-driven hydraulics.

The HX2 can follow an adjustable, pre-programmed GPS path and is equipped with a vision system allowing it to detect obstacles in its path