On Sat, 19 May 2012 23:36:40 +0000 (UTC), Denis McMahon
wrote:

On Sat, 19 May 2012 17:20:35 +0100, Robin9 wrote:

I imagine the main motor manufacturers are investigating possibilities
for goods vehicles including diesel/electric hybrids.

Isn't the new "London Bus" such a hybrid? Given that the carrying
capacity of most vehicles is related to the size, I don't see why a Prius
sized "car-derived-van" couldn't use the Prius system, nor why it can't
be upscaled to match the increased vehicle size for eg ford transit /
mercedes sprint / vw transporter etc sized vehicles.

Probably because a Prius isn't much more economical than a modern euro
diesel, but is much more expensive. Diesels don't sell in the US car
market, hence the need for hybrid petrol cars. But commercial vehicles
are usually diesels, even in the US, and the benefits of hybrid
propulsion are smaller for diesels (as they're more efficient in
part-load conditions). The NB4L is a range-extender (similar to the
Ampera), and they tend to be more efficient, particularly if you
charge the batteries overnight at lower cost.

The Prius is far more economical (in terms of fuel consumption) than a
diesel engine car when driving at low speeds in urban streets
with innumerable stops for traffic signals and other vehicles.
On open roads, particularly motorways, a diesel is more economical.
Previously I was driving a diesel engine car and I'm very conscious
of the difference in my fuel consumption!