Dual-mode vehicle

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See also Global Hybrid Cooperation for the General Motors/DaimlerChrysler/BMW hybrid vehicle technology often called "Dual-Mode"

A dual-mode vehicle is a vehicle that can run on power from two different sources (hybrid vehicle), typically electricity from overhead lines or ground level power supply and in parallel or alternating from an internal combustion engine burning liquid fuels or gas.

1 Technology
2 Logistics
3 Motivation
4 See also
5 References

[edit] Technology

'Dual-mode' was first used for trolleybuses capable of running also on diesel for part of their route. Dual-mode operation is useful mainly for big vehicles because of the costs of the electric power supply. Thus especially busses and trucks are candidates to be equipped with dual-mode propulsion systems.

Both propulsion systems have apimately the same output at the power train so the maximum velocity in both modes is comparable.

The ground level power supply system is well known by children playing with cars at miniature racing tracks using vehicles with rubber tires and DC-power rails (which have also a guiding function). Because of the health risks with higher voltages in real systems, the power rail is only switched on when a vehicle is covering the section thus preventing pedestrians from being injured. This system is used in Bordeaux with trams and is called Alimentation par Sol(Pictures of the power rail). The French wikipedia article states that it is three times more expensive than the catenary system.

Hybrid vehicles differ from dual-mode vehicles because they may not be fed by another energy source during operation (there might be an exemption for a hypothetical hybrid solar vehicle).

[edit] Logistics

On the main urban arterial streets a catenary system may serve both public transport and freight forwarders. This has great synergic effects making the operation of trolleybuses more efficient because of the additional income from freight forwarders. The operation of dual-mode trucks is not bound to the electric system. The distance from the logistics centre to the inner city is driven in a conventional way. Also there is the possibility to reach all clients aside the catenary system.

[edit] Motivation

Cities with slow air exchange (inversion) and high emission figures (particulate matter PM₁₀, PM_2.5, NO_x, Ozone) caused by diesel-powered vehicles, need a way to reduce big pollution sources. Commercial diesel-fueled vehicles are prime targets because of their high NO_x and PM emissions caused by the lack of sufficient pollution controls.

[edit] See also

[edit] References

The best suited power supply was discussed attached to the EV-World article "The DualMode EV Revolution" [1]. There are a few sites so far discussing electric power supply systems, partly having a guiding function. The term dual-mode vehicle is also used for dual-way vehicles capable of using both roads and tracks.