Trucks with e-axles to proliferate

The 2025 Brisbane Truck Show (May 15-18) looks likely to have an increased focus on electric axles (e-axles), which have the potential to boost the efficiency and environmental performance of both truck and trailer setups – especially for refrigerated transport.

Since a handful of e-axle technologies were showcased at the 2023 Brisbane Truck Show (the event is held every two years), e-axles have emerged as a key development in the push towards more sustainable transportation.

E-axles are becoming increasingly efficient, cost-effective, and adaptable to a variety of applications. They are also on the radar for applications outside of heavy goods transport, with caravan manufacturers and their suppliers quietly investigating ways of overcoming the battery range implications of towing with electrified vehicles.

Before diving into some of the standout E-Axle innovations from the 2023 show, here’s a brief recap of the technology.

The technology

An e-axle is a compact, integrated unit that combines the electric motor, power electronics and transmission, typically linked to a lithium-ion (Li-ion) battery pack.

In diesel trucks, e-axles are integrated into either the prime mover axle or the trailer’s axle, assisting with propulsion and/or enabling regenerative braking energy recovery in the name of improving fuel efficiency.

For businesses unable to invest in new fully electric trucks, retrofitting existing diesel vehicles with e-axles can offer a cost-effective way to reduce their carbon footprint without replacing entire vehicles or fleets.

Why e-axles make sense for trucks

E-Axles provide instant torque response, offering smooth and immediate acceleration. Less reliance on the diesel engine at low speed or under acceleration can also help reduce operational noise.

Because e-axles condense components into a single unit, they can result in a simpler and more compact axle design that also frees up space for battery storage inside the truck’s protective frame rails.

However, most propulsion e-axle designs rely on ‘super single’ tyres that come with payload restrictions in Australia, complicated by each state having its own criteria.

The rolling resistance and aerodynamic advantage of single- rather than dual-tyre arrangements is compounded by the use of an e-axle, resulting in fuel use savings of up to 20 per cent.

Powered trailers are being trialled overseas and Australian regulations might hamper the same taking place here for some time but energy recuperation is the big opportunity.

Regenerative braking extends brake life by capturing energy during deceleration and overall driveline efficiency can be improved by reducing gear losses.

Some e-axle designs can recuperate energy under deceleration and acceleration when used with a diesel prime mover but for now the immediate future for Australia is in recuperation, primarily for running refrigerated trailers without relying on diesel.

E-axles to look out for at Brisbane Truck Show

SAF-Holland TRAKr

SAF-Holland’s TRAKr E-Axle can generate up to 20kW and and is already operational on Australian roads as part of a McDonald’s fridge trailer built by FTE.

The TRAKr E-Axle captures kinetic energy and converts it into electricity. This stored energy powers accessories like fridge units, lifting platforms, or cranes, significantly reducing reliance on diesel generators.

Notably, the TRAKr system does not rely on rare-earth minerals or copper, aiding sustainability claims.

Dana Spicer eS9000re

The Spicer eS9000r is a fully integrated drive axle suited for vehicles with a GVM of up to 10.6 tonnes and can be retrofitted to replace an existing truck axle.

Combining the motor, power system, and transmission into a single unit, it delivers 237kW of power and up to 9000Nm of torque while weighing just 370kg.

BPW Transpec ePower Axle

BPW Transpec’s regenerative unit uses two generators to double the power and reliability of the system.

The company claims that this technology can save up to 4000 litres of diesel per year in specific applications. 

Intelligent energy management ensures that battery reserves are effectively controlled, even in heavy traffic or during long journeys, while its own cooling system further enhances efficiency and longevity.

VE Motion E-Trailer and parallel hybrid system

Local innovator VE Motion’s E-Trailer system integrates a fully powered e-axle while the parallel hybrid system can be retrofitted to diesel trucks.

These systems are designed to reduce diesel fuel usage by up to 50 per cent while retaining the range benefits of diesel trucks.

VE Motion’s hybrid truck system operates much like parallel hybrid systems in passenger cars, where an electric motor and battery sit between the transmission and driveline.

Move Engineering Group’s powered trailer concept

Aiming to reduce diesel use by 58 per cent and cut emissions by half, Move Engineering Group’s  groundbreaking powered trailer concept has been described by Heavy Vehicle Industry Australia (HVIA) chief technical officer, Adam Ritzinger as a visionary approach to enhancing freight transport efficiency.

“The concept of a ‘powered trailer’ stems from the idea to add either regenerative energy and/or motive power capabilities to a heavy goods trailer,” said Mr Ritzinger.

“It is an incredibly innovative and exciting freight transport decarbonisation opportunity that has recently emerged from within HVIA’s member base.”

What makes this technology even more appealing is that it can work with any type of prime mover – diesel, electric, or hydrogen-powered – making it highly versatile. 

Additionally, the system can increase gross combination mass (GCM) and help extend the driving range for electrified vehicles.

Given all these systems have different thermal management requirements, e-axle adoption looks like a win-win.