When you picture a quarry or mining site, you probably envisage mammoth machines and humungous haul trucks with 100-ton loads and human-sized wheels. Because bigger means better, right?
The issue with vehicles of this scale is that when they’re in action, they splutter harmful CO2 emissions. It was this challenge that motivated our research project back in 2015: what if these fossil-fueled behemoths could instead be powered by batteries, thus reducing environmental impact?
With the technology available at the time, it soon became clear that electrification in this format wasn’t a practical option. For one, we’d need to add a lot of batteries, which is very costly. Secondly, extra batteries equal excess weight, making the process far less efficient. That’s when we turned our attention to the trucks themselves.
The quarrying and mining industry has remained largely unchanged for the past 50 years – two or three gigantic machines has always been the norm. As production increases, so does the size of the vehicles involved. Logical, right?
But what if we turned this theory on its head? What if, in fact, bigger isn’t better? Instead of two huge machines, why not a fleet of small ones? From work-harder elephants to work-smarter ants.
Downsizing means the weight and capacity of batteries is no longer an issue, therefore enabling electrification. Smaller machines and a continuous opportunity charging concept present a completely different opportunity. And we’re able to share battery technology with our colleagues within the Volvo Group, who have used similar batteries in the past for hybrid buses.
But it’s not just from a sustainability point of view that downsizing is changing the game. There are also multiple benefits from a process perspective.
Over the years, hauling trucks have grown to reduce operators – this means the loading tool has also grown to match the bigger vehicles. So, while upscaling of hauling tools does reduce operators, companies are landed with a larger loading tool that’s utilized less.
In principle, this means just to save operators, companies must increase capacity on the loading side they don’t really use, essentially adding a non-utilized capacity to their process.
If we switch this thinking around and instead choose smaller vehicles, we can reduce the size of the loading tool (and in turn, the cost) and increase utilization, because there are more transport vehicles in the process. This is greatly beneficial from both a commercial and process perspective.
When you're working with, for example, 100-ton trucks, the only way to modify production capacity is by adding or removing a vehicle. On the other hand, if a company has a fleet of smaller vehicles, it can adapt more easily. Similarly, if one of a pair of 100-ton trucks goes down, 50% capacity is lost. Compare this to a fleet of 10 smaller vehicles – one vehicle going down only equates to 10% capacity lost. In this regard, downsizing increases uptime and therefore productivity – you could also call this increasing process resolution.
Smaller trucks also mean smaller haul routes – these narrower routes enable better utilization of quarries and mines and in turn better utilization of the available material. And if a company’s process demands trucks to pass one another, smaller vehicles make things a lot simpler.
But here’s the thing. Downsizing is not a 1:1 replacement. Companies can’t simply do away with their old vehicles, beckon in a fleet of small machines and expect an instantly better outcome. A downsized fleet demands a wider perspective from a planning point of view. Potholes that wouldn’t perturb a human-sized wheel present a challenge for smaller tires; a downsized wheel loader means smaller blocks of material that can be handled.
But these challenges are minor in the grand scheme of things and with proper planning, a downsized fleet can consistently produce better material and make operations run a lot more smoothly.
At Volvo Autonomous Solutions, our years of research within the field of downsizing has resulted in TARA, a complete autonomous haulage system designed for use in confined areas such as quarries and mines. Consisting of a fleet of Volvo TA15s, the TARA solution cuts emissions, increases efficiency and optimizes machine utilization. It’s also offered as Transport-as-a-Service, meaning companies only pay for the services they use, rather than buying costly machinery.
As I’ve previously mentioned, not much has changed process-wise within mining and quarrying in the last 50 years, so the biggest barrier that exists to downsizing today is not technology, but rather a conservative mindset and focus on experience.
The switch to smaller machines is a change management question. How can you persuade people that something they’ve been told for half a century is no longer right? Therefore, alongside rapidly evolving technology, education is just as important – we need to get the operators and people involved in the process on board for the shift to happen.
Technology is one thing, but without adoption from humans, the concept of downsizing will remain the elephant in the room.