Before emerging technologies are even considered viable for widespread use, their utility has to undergo a trial by fire, typically in scenarios that mimic real-world jobsite conditions. A novel concept that looks great on paper may be good for stoking the imagination, but without being proven in the real world it’s little more than theoretical, and therefore of limited practical use.
Electric construction equipment and autonomous machinery are two relative newcomers to the industry, and although both technologies show great potential for the future of the jobsite, they’re both in the early days of adoption. Volvo CE and Skanska Sweden are looking to move the needle on proving that potential. In a first-of-its-kind study, the companies are leveraging both technologies at a real jobsite which they say will reduce carbon emissions by 95% and the total cost of operations by 25%.
Volvo CE and Skanska Sweden are close to completion on an ambitious 10-week trial of a nearly emission-free quarry combining both electric vehicles and automation. The concept, known as Electric Site, is located at Skanska’s Vikan Kross quarry near Gothenburg, Sweden. The goal, according to Volvo CE, is to power each stage of quarry transport almost entirely with electricity, from initial excavation to primary and secondary crushing, using electric haulers and excavators.
“This is the first time that anything like this has been attempted in the quarrying industry and, if successful, Electric Site could serve as a blueprint for transforming the efficiency, safety and environmental impact of quarries around the world,” said Gunnar Hagman, CEO of Skanska Sweden.
In order to pull the concept off, the companies had to reevaluate everything they thought they knew about how work gets done, and adapt their machinery along with their thinking. Instead of three rigid haulers, the site uses eight autonomous HX2 battery-electric load carriers. These prototypes are smaller than their traditional counterparts, and are used to carry material from the primary mobile crusher to a second static crusher, according to Volvo CE.
The HX2 was developed by Volvo as a follow-up to its proof-of-concept HX1, which made its debut in 2016 at the Volvo Exploration Forum. Since then, the company has refined the technology and added considerably to its functionality and autonomous capabilities.
“Once we knew it was feasible, we updated the design requirements for the HX2 to incorporate shared technologies and components from the Volvo Group, such as electric motors, batteries and power electronics,” Uwe Müller, chief project manager for Electric Site at Volvo CE told For Construction Pros.
“Integrating a completely new drivetrain was crucial to take full advantage of the groundbreaking electromobility developments that are happening inside the Volvo Group. Another new feature is the addition of a vision system, which allows the machine to detect humans and obstacles in its vicinity.”
Electric Site’s primary crusher is the dual-powered, 70-ton EX1 excavator, a prototype based off of the Volvo EC750, which has been kitted out with an electric motor in addition to its usual diesel engine. This was done without altering the user controls or even increasing its size, Müller told For Construction Pros, which he said required “a significant amount of repackaging work.”
“However, in terms of the operator interface and controls, nothing has changed – it’s operated in exactly the same way as a conventional Volvo excavator. If the cable is connected, the machine will automatically start in electric mode. If it’s not, it will start in diesel mode,” Müller said.
Since the EX1 will mostly remain in place, having both a diesel engine and electric motor offers flexibility in how it gets powered. Electricity for excavating work, and diesel for the occasional instances where it needs to be quickly moved or repositioned.
Rounding out the trio of electric/autonomous vehicles at Electric Site is Volvo’s prototype electric hybrid LX1 wheel loader, which improves on fuel efficiency by up to 50% while operating more quietly and greatly reducing emissions over conventional machinery. The company says it can do the work of a loader a full size larger than the LX1.
Volvo CE and Skanska’s 10-week trial run of their experimental jobsite at the quarry is nearly complete, and it will be interesting to see what lessons the companies take away from the trial and how they use that knowledge to iterate on future products. For electric and autonomous machinery, Electric Site has been a rigorous proving ground, and it’s likely to be cited going forward as a legitimate proof of concept for the technology.