Trailer technology: The stepping stone to long-distance truck electrification

Long-distance truck electrification is starting to become a reality in Australia, but the road ahead is long and complex as we have to roll out charging infrastructure and progressively replace every prime mover in the fleet.

Prime movers are an expensive asset and they are kept running over long lifetimes. A quick scan of trucksales.com.au shows that there are over 200 prime movers from 2006 or earlier advertised for sale, some with over 1,000,000km on the clock and still fetching good prices.

No matter how well painted a 20-year-old truck is, it is not going to be as efficient as a new one, and diesel trucks bought today may take 20 years or more to cycle out of the logistics chain. That’s a long tail of diesel smoke and carbon emissions.

Luckily we are starting to see trailer-based solutions that can improve the efficiency of moving loads from A to B. Refrigerated trailers have a second ICE engine in them that runs a generator to power the refrigerator. In a hot country this consumes a lot of diesel to do so. There are two solutions to this problem currently testing on the roads of Australia and New Zealand.

Firstly we have Protran, who are demonstrating the Endurance trailer from UK outfit Sunswap. This combines a solar array on the roof of the trailer with a battery to power the refrigeration unit.

In a recent test on an 11,671km round trip from Sydney to Brisbane, the trailer maintained temperature over 32 hours of continuous operation—58.9kWh coming from the sun and another 27kWh coming from the battery.

This saved 64 litres of diesel and 172kg of CO₂ emissions. The system is designed to be a drop-in replacement for existing refrigeration units, making it simple for body and trailer builders like Protran to adapt it into their design.

This isn’t the only solution looking to address the costs and emissions of refrigeration. Australia has its own challenger in VE Motion.

VE Motion has two key technologies that can be fitted to trailers: the regenerative energy axle, which acts as a regenerative brake, capturing energy by slowing the truck as a BEV or hybrid would; and the motive power axle that can be used to provide an electric assist of up to 295kW in a way that is transparent to the driver. These can be combined with batteries from 200kWh to 600kWh.

The regenerative axle is available today, but the motive power axle is not currently compliant with the current Australian Design Rules. VE Motion are conducting trials in Australia and New Zealand to prove the technology and advocate for a rule change that would allow this technology to be widely deployed.

VE Motion claims they are able to achieve not only a diesel saving of up to 50%, but savings in maintenance to brakes and other components – a saving that BEV drivers will already understand.

Of course full electrification is the goal, but these technologies provide an important stepping stone, not least because we are a country of Doubles and Road Trains. Our prime movers are designed overseas for much less arduous duties, so distributing power and offloading some of the batteries and powertrain along the length of the vehicle will enable moving the kind of loads the Australian trucking industry is used to.

Listen to the latest episode of The Driven Podcast on the electrification of road freight here, or wherever you get your podcasts.