Furrer+Frey proposes tractor swapping for long-haul trucks

Opbrid Trůkbaar truck1

While short-haul applications such as local delivery trucks, port drayage trucks and city buses are perfect candidates for electrification, long-haul trucking will likely prove more of a challenge, because of battery-electric vehicles’ limited range.

Now Furrer+Frey, a Swiss firm that provides a wide range of rail transport products and services, has proposed a simple, low-tech solution: tractor swapping.

In a recent presentation outlining the concept, Roger Bedell, Product Director of Opbrid Fast Charge Systems at Furrer+Frey, noted that a variety of solutions have been suggested for shifting long-haul trucking to electric drive, including the use of overhead catenaries; in-road inductive charging; ultra-fast battery recharging; and battery swapping.

The first two require major investments in infrastructure; the third relies on heavier, lower energy density LTO batteries and ultra-high charging rates; and the fourth is technically difficult, given the size of the battery packs and the need for dedicated swap stations.

Under the proposed tractor swapping model, a tractor-trailer with a low charge pulls into a station where a fully charged tractor is waiting. The driver switches tractors and departs with a full pack, leaving the first tractor to recharge.

A couple of enabling technologies could streamline the process:

  • The Jost KKS automated coupling system, a fully automatic driver assistance system that controls all functions of the coupling and decoupling process, including an automated interface for pneumatic and electric connections.
  • The Furrer+Frey Opbrid Trůkbaar, an overhead high-power charging system for heavy-duty vehicles that supports power levels up to 650 kW.

A tractor swapping system would be simple and fast, with no need for special infrastructure. However, Bedell graciously pointed out that there are a couple of disadvantages. Precise scheduling would be required to avoid idle tractors, and delays could propagate through the system, as is the case with air travel. Such a business model would also favor large shippers.



Source: Furrer+Frey via Green Car Congress

  • brian_gilbert

    1: Tractor swapping would also be useful in connection with completely driverless zones/countries, A driven tractor would be used outside the zone and hand over to a driverless tractor at the border of the driverless zone/country.

    2: The driverless tractors would probably be owned by a hire company licenced to operate in the zone. There would therefore be no problem having it waiting ready-charged at the changeover point, There would also be no problem with swapping to another driverless tractor during long journeys.

    • rogerbedell

      Of course. Tractor swapping is completely compatible with driverless vehicles. In fact, I talked with some Volvo engineers who said that the complete tractor swap operation can be automated now, letting the driver rest (or get a coffee). Then the swap operation doesn’t eat into driving time.

  • Geoff

    Wouldn’t putting batteries in the trailer be a better solution? Having an electric tractor with enough onboard range to get to the trailer (from previous job or charge station) then couple it to long range batteries on the trailer for the line haul seems more effective.

    Trailers sit for hours at depots and warehouses so have a better opportunity to be fast charged, and are hauled 1000+km each night. You’d still need the same battery capacity on the road to cover the range, however eliminate swapping time and the capital cost of the additional tractor units.

    • brian_gilbert

      You need to do a project spreadsheet for the alternatives to decide and it might be best in some places but not others. THe commonest batteries used (lithium-ion) are very heavy and very costly per kwh. Trailers are more likely to be idle than tractors and you do not want the expensive battery to be idle.

      No large system is likely to go live within 5 years becuase it must involve a government and therefore politics. In that time battery texhnology will have increased significanly. Hopefully batteries by then can be fast-charged and a lot cheaper and lighter per kwh, One favourable factor is that lithium-ion batteries are only preferred now becuase driven electric vehicles are only used a small,part of the day. (Their capaciry reduces with use.) With high usage per day other types are more more suitable/cheaper per kwh.

      • rogerbedell

        What I’m looking for is the transport case with most diesel use per vehicle per hour. Then the business case that exploits the cost differential between diesel and electricity goes to its maximum. Long haul trucks are the highest users of diesel in the transport arena, therefore, they are the best targets for electrification. If the business case is validated, we don’t need to wait for governments.

        • brian_gilbert

          Offhand another high user of diesl vehicles would be a taxi operator where the vehicles operated 24 hours a day with drivers working shifts. I think most London Taxis are diesel but there is currently talk of taxing diesel vehicles smore because of the new measure of how much harm the gasses do”