TRUCK & TECH
ZERO EFFECT
In the right application opportunities will arise to maximise the full potential of PBS and take productivity to the next level as industry confronts the challenge posed by Zero Emissions Vehicles explains Tiger Spider Managing Director Marcus Coleman.
Marcus Coleman.
A
ustralian High Productivity Vehicles like B-doubles, roadtrains and PBS combinations have a unique set of challenges and opportunities when it comes to Zero Emissions. Compared to smaller urban trucks and buses HPVs travel long distances and consume huge amounts of energy. Battery electric powertrains have proven to work for buses and show promise for urban delivery and garbage trucks which travel less than 250 km per day and return to base for overnight charging. Elon Musk is promising an affordable Tesla prime mover with 500 km to 800 km range. It remains to be seen if this will hold true towing an Australian tri-axle semi reefer van let alone an 85-tonne PBS A-double. We’ve modelled various heavy
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electric powertrains using available electric motor, battery, and fastcharge technology and certainly some applications are feasible. But long distance electric High Productivity Vehicles are still some time away without significant battery improvement, massive fast charger deployments or advances in hydrogen based product options. However, the bevy of new EV technologies does provide ways to improve high Startability, Gradeability and Acceleration Capability performance. These PBS standards will become increasingly relevant as we progressively overcome road infrastructure limits. On-highway engine power has been constrained by emissions regulations and Australia’s reliance on overseas suppliers. While engine manufacturers have larger options available, they don’t support on-highway emissions beyond 600hp and 700hp. This is critical for PBS since speed on a 1 per cent grade performance caps GCM. The NHVR has been negotiating with road managers to remove the prescriptive pavement horizontal loading requirement which limits GCM of tandem drive prime movers to 70 tonnes (Level 1), 85 tonnes (Level 2), 110 tonnes (Level 3) and 150 tonnes (Level 4). This follows
recommendations made by the 2015 Austroads PBS Level 3 and Level 4 Standard Review. It is a useful change but only helps a little with existing prime movers. PBS vehicles are supposed to offer equivalent or better performance to the existing fleet, but this is impossible if we add an additional axle group or two (often between 15 to 50 tonnes more payload) and don’t increase power and tractive effort for Gradeability (A) - maximum grade percentage and Gradeability (B) - speed on a 1 per cent grade. PBS driveline requirements are already difficult to achieve for PBS Level 3 and Level 4 vehicles. Main Roads WA overcame this for remote and regional areas by relaxing the Level 4 standards and requiring only that a more appropriate prime mover is not readily available on the market. This is a pragmatic approach, which works for remote areas, but won’t be accepted by the Eastern states and in higher traffic areas. Ultimately, more power is required and that’s been too difficult to achieve with on-highway emission requirements. But electric motors don’t have these constraints and are already available with peak power ratings over 250kW per axle. With this technology we could
