Utility vehicles for underground use are edging toward an electric future, driven by improvements in battery technology and the absence of exhaust emissions
The effectiveness of a mine’s utility equipment fleet can have an influential role in dictating the operation’s overall level of performance. For example, underground mines lacking sufficient or reliable crew-transfer and craftsman vehicles can suffer from less-than-optimal shift productivity and delayed repairs to crucial equipment.
E&MJ’s most recent coverage of personnel carriers and other utility vehicles suitable for underground use (See The People Movers, pp. 46–51, May 2015) presented a wide range of choices that included everything from above-ground units modified for underground use, to specialized vehicles designed exclusively for below-ground operation. Most of the vehicles mentioned were diesel-powered, and even now—more than a year later—when it comes to mobile utility vehicles, diesel power remains king of the underground road. However, as the industry focuses more intently on reducing overall energy consumption, electric-powered units are getting increased attention from both manufacturers and customers.
In fact, an executive of a company that makes battery-powered electric drivetrain systems for mining and other industrial vehicles recently asserted that diesel power’s firm grip on underground power solutions will soon begin to loosen—and perhaps rapidly fade. Mike Kasaba, CEO of Artisan Vehicle Systems, Camarillo, California, USA, told an audience at a recent Canadian conference on mining diesel emissions that within half a decade, he believes the lion’s share of underground equipment sales will involve zero-emission equipment, and that diesel options will be gradually phased out. Artisan’s battery-based drive systems currently power more than a dozen scoops and haul trucks at Kirkland Lake Gold’s Macassa mine, and the company said it can integrate its technology into any kind of underground mobile mine equipment—although LHDs and haul trucks are currently considered the “low-hanging fruit” because of their larger engines and corresponding emissions levels that have a greater impact on ventilation requirements.
Within the OEM camp, Joy Global reported in late June that it had formed a strategic partnership with the Voltabox subsidiary of German automotive equipment supplier paragon AG to develop smart battery systems for mining equipment. The company said the benefits of lithium-ion technology, coupled with advanced energy system design, active thermal regulation and smart battery management, will provide equipment performance and cost advantages not achievable with any other drive technology currently available on the market. During the first stage of the arrangement, Voltabox, based in Austin, Texas, USA, will develop smart battery systems for use in Joy’s underground mining equipment. Joy said the first deliveries of complex battery systems were scheduled to occur in its 2017 fiscal year.
Battery-powered units such as Industrial Fabrication Inc.’s MineUte UT150-eMV personnel transporter have been available for some time now and more are on the way. Herman Paus Maschinenfabrik GmbH announced recently that the new generation of its MinCa mine transporter is now available, based on the proven MinCa 18A concept—a versatile vehicle that can be adapted to diverse customer requirements. The most notable aspect of the machine is its multiple drive system options: the new MinCa is available with a Deutz diesel engine generating 85 kW at 2,300 rpm and a hydrostatic drive; a hybrid version that generates 50 kW and offers battery life approaching 12 hours; or a fully electric model generating 50 kW and with an operational range extending three to four hours, which the company said will be increased in the near future. Featuring compact dimensions of 3,998 mm x 1,725 mm (157 x 68 in.) and a payload of 1,200 kg (2,650 lb), Paus said the MinCa 5.1 is well-suited for underground duty in even narrow-vein operations.
Movement in the utility-equipment sector toward electric or hybrid-powered propulsion systems is flowing in parallel with activity at production-equipment builders such as Atlas Copco and Sandvik Mining. Earlier this year, Atlas Copco introduced its Scooptram S7 Battery—the company’s first battery-powered LHD; and Sandvik said it will soon unveil the DD422iE, an electric drill jumbo that runs on battery power while tramming and recharges those batteries while it drills.
As is the case with most high-tech trends, the hardware and software is developing and improving faster than the targeted industry’s ability to put it immediately to use. However, one Australian company that has entered the underground utility vehicle market hopes mine operators will quickly recognize the actual and potential claimed advantages of its new, innovative specialty vehicle, the Tomcar LV1 for mining. John Miller, editor of E&MJ’s sister publication The Asia Miner, recently met with the vehicle’s developers and filed the following report.
The new Paus MinCa utility vehicle offers a choice of three power options: conventional diesel, hybrid or battery.
Made for Mining
Tomcar Australia has developed an electric-powered off-road light vehicle aimed specifically for use in underground mining. The company has spent two years designing its production electric car, with the zero emission Tomcar LV1 launched in mid-May. Full-scale production is expected to begin in November and customer deliveries are expected to commence in February 2017.
The vehicle has been designed by Tomcar Australia and is being built at Tomcar’s Melbourne production facility where it has an association with vehicle component maker MTM Auto. Tomcar Australia CEO and Co-founder David Brim said the vehicle has been developed in close consultation with key miners. “We’ve worked with them throughout the design process. We’ve taken the prototypes into mines, and made changes to fit their use. Mining companies are used to buying off the shelf passenger vehicles and modifying them for use in an environment they are not designed for. We are selling a custom-made, zero emissions product.”
The original Tomcar had development roots in military and law-enforcement applications. The founders of Tomcar Australia came across the original vehicle in 2004 and in the ensuring years transformed the concept into a commercially viable vehicle that incorporates more than 180 engineering improvements. The original Tomcar, the company noted, was built to survive parachute drops—making it the strongest vehicle in its class, featuring a fully welded ROPS steel safety cell that is integral to the frame.
Brim explained that “In 2013, we were approached by some major miners who recognized that Tomcar would also be suitable in this field, but with a few changes. The transformation started in early 2014 and we spent two years developing a mining variant [that] has fully waterproof wiring, a corrosive resistant frame, glow in the dark panels, LED lighting, along with special seating and seatbelts to suit mining applications, particularly in underground situations. We initially planned a diesel vehicle, but in 2015 decided to leapfrog the diesel technology and go fully electric.
“The LV1 is our first foray into electric vehicles and we’ve designed and developed the electric drivetrain. We have come up with a military-grade platform coupled with a robust, fully waterproof electric motor. The connections are all IP 66 rated and it is designed to last a lifetime.
“There are five-seat and two-seat utility versions in the mining variant. They are primarily for operators to get around the mine easily and the larger model can carry up to 1 ton of gear.”
The frame comprises more than 200 pieces, which are welded on special jigs. A unique coating of titanium and zinc designed to reduce corrosion gives it a silver appearance. The original frame design has been altered to make it easier for miners to get in and out while wearing their bulky workbelts.
Battery-powered vehicles such as the MineUte UT150-eMV have an advantage over diesel equipment underground in that the electric drivetrain by itself causes no requirement for ventilation.
At present Tomcar builds two vehicles a week, but the company said this can be increased as demand increases and the electric vehicle comes on line.
Brim noted, “Everything is symmetrical so that parts on the left also fit on the right and vice versa. It is easy to maintain, there are grease points throughout and everything is rebuildable. The utility vehicle has an aluminum tray but the mining version will have a stronger mine-spec version.
“The mining Tomcar is fully enclosed with strong metal doors and a roof designed for strength in underground situations where falling rocks can be an issue, and air-conditioning is an option. On standard Tomcars, lighting is incandescent but in the mining variant it is LED. Another unique feature is that every nut, bolt and rivet is stainless steel to prevent corrosion.
Brim explained: “We took the first prototype to a mine site for trial and operators said we needed to make a few changes, so we went away and did this. We took their ideas seriously and they were pleased we listened to them, made alterations and brought the car back for further trials. We changed the seats because of feedback, we changed the seatbelts, doors and wiper system, and we changed the instrument panel so that it is now a fully waterproof, human interface device.”
“The initial target is Australia, but because Australian mining companies operate globally, we have global aspirations and these vehicles will be ideal for any mining situation,” Brim said. “These vehicles will result in mining companies saving on fleet costs but also with operating and maintenance. They will retail for A$75,000, which is the same price as standard road vehicles imported from overseas, but the zero emissions from the electric drive will cut [ventilation] costs, reduce health and safety concerns because they are specifically designed for mines, and dramatically reduce maintenance costs because the car is much simpler.
“We concentrate on direct sales channels with customers as well as on research and development. We will sell the mining cars direct to miners; there will be no dealer or middle man. In this way, we get to deal directly with customers and understand what their needs are and how they are using our vehicles.”
In response to any concerns about battery life and vehicle availability, Brim explained that “you need to think of an electric vehicle like you do your phone—very rarely do you let it run out of battery and when it does you just charge it again. With EVs you continuously charge them during the day. The lithium-ion batteries we use are not damaged if you keep topping them up, unlike lead acid batteries.
“The Tomcar has fast charge points enabling an entire six- to eight-hour shift to be charged in around 20-30 minutes. When it is not being used, we suggest it be plugged in to ensure it is always charged. We offer a variety of charging solutions and battery pack options, depending how deep the mine is, how hot it is and how far operators have to drive. When the car is being driven down the mine the batteries are charging, but when coming up they use more power.”
“The Tomcar’s defense background makes it easy to maintain. When you are in a conflict situation and the car breaks, you need to be able to fix it very quickly, so a lot of the design that has gone into the Tomcar is with the aim of making things easy to maintain and repair. The mining industry on average spends A$7,000 to A$10,000 per month on maintenance of a light vehicle, but the Tomcar LV will cost around A$500 to A$1,000 per month depending on its use.”
For example, he noted: “Standard vehicle braking systems are very hard to clean because it is difficult to access, which is why a lot of mining companies require expensive sealed wet brakes. With a Tomcar they are exposed and very easy to clean. Even if they do wear down they are not expensive, or difficult, to replace.
“Although it is two-wheel-drive, the Tomcar outperforms almost all four-wheel-drives. We don’t have complicated four-wheel-drive linkages, which eliminates that problem. The wiring is very simple and there is less to fail. With most modern vehicles you can only have so many short circuits before the wiring fails and cannot be fixed, but with a Tomcar the wiring loom is replaceable. For the first time in history, the wiring loom has become a consumable part—there is no other car in the world like that.”
Builders of the Tomcar for mining claim a 30-minute charging session will be sufficient to provide a six- to eight-hour shift range. They plan to extend its potential use into coal and surface applications.
Brim continued: “We want Tomcar to be the go-to light vehicle for underground hard rock mining situations but we aim to develop the brand further with versions for coal mines and open-cut mines. Safety requirements for these applications are different but the Tomcar is much safer than other light vehicles—they are less prone to rollovers, have a lower center of gravity, and are much more robust. A 12-point safety harness is an option.
“We are working with the coal industry to change battery use regulations as there are restrictions for lead acid batteries, which encompass lithium-ion variations. We build the batteries ourselves and they are fully waterproof and spark-proof, which makes them very safe. Once the coal industry allows these batteries, this car will be a perfect opportunity to reduce costs.”
He explained that once the electric vehicle fleet is digitized it will be easy to add benefits. “It will be possible to create a tag-along situation where five or six cars can be driven down and after the people and equipment are unloaded, one operator electronically tags them together and drives the lead vehicle out with the other driverless vehicles following,” he said. “Electronic vehicles can be autonomous and the tag-along system will be pseudo-autonomous.
“Digitization will also mean that where people are working underground, transponders can be placed either side of the work area and vehicles will automatically slow down to make conditions safer for everyone. It will know when it is underground and slow down, it will know when it is out of the tunnel and speed up. It is a very intelligent design.”