Current battery technology places the same range restrictions on electric commercial trucks as on electric cars.

So while electric trucks may be suitable for local delivery service and other short-range operations, they can't cut it in long-haul trucking at the moment.

However, Swiss rail-infrastructure company Furrer+Frey has a fairly simple and low-tech solution: tractor swapping.

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Furrer+Frey—which provides equipment for rail electrification—recently acquired Opbrid, a developer of overhead-pantograph charging systems for trucks and buses.

The combined companies (as Furrer+Frey Opbrid) are now investigating ways to electrify long-haul trucks.

Tractor swapping may be one of the most straightforward ways to accomplish that, argued Opbrid founder and current Furrer+Frey executive Roger Bedell in a recent presentation covered by Green Car Congress (via Charged EVs).

Volvo Concept Truck

Volvo Concept Truck

The proposed tractor-swapping model calls for a truck with a nearly-depleted battery to pull into a station, where a fully-charged tractor would be waiting to pick up its trailer.

In a way, it's similar to the current procedure of the Formula E electric-car racing series, where drivers swap cars mid-race.

Certain commercially-available hardware could facilitate this process, Bedell noted in his presentation.

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One is the Jost KKS automated coupling system, which can couple and uncouple tractors and trailers with minimal driver involvement.

This would theoretically speed up the swapping process.

To ensure tractors get charged in preparation for swaps, Bedell volunteered his company's own Trukbaar system.

Furrer+Frey Opbrid Trukbaar charging system

Furrer+Frey Opbrid Trukbaar charging system

This DC fast-charging system uses a pantograph like the ones used to power electric trains.

Even with the necessary charging stations, Bedell claims tractor swapping would be the least complex option for electric long-haul trucks in terms of infrastructure.

However, he also noted that there are some potential drawbacks.

Fleets of tractors and trailers would need to be equipped with the KKS coupling system in order to cut swapping times.

Daimler Trucks North America SuperTruck

Daimler Trucks North America SuperTruck

Swaps would also have to be precisely scheduled, and delays could propagate throughout the system, similar to what happens with air travel.

Tractor swapping also favors large shippers that have substantial fleets of tractors.

Still, it's one possible way to get electric semi trucks on the road, even if battery technology doesn't allow for the range operators need right now.


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