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Recliner[_3_] · December 12th 16, 12:11 PM posted to uk.transport.london

On Mon, 12 Dec 2016 09:39:45 +0000 (UTC), d wrote:

On Fri, 9 Dec 2016 11:05:44 -0800 (PST)
DRH wrote:
The Red Arrow BYD / Alexander-Dennis Enviro200EV buses have iron-phosphate =
batteries at the rear and in the roof pod, which also incorporates the airc=
on unit. The driveline comprises two 90kW wheel-hub motors and water coolin=
g system plus regenerative braking system.

Wheel hub motors? They're a poor idea as they massively increase unsprung
weight. Also I'm surprised they could fit motors powerful enough in the wheels
with enough cooling for a bus tbh. Hope westminster has increased its pothole
budget.

They do increase the unsprung weight, though they also save the weight
of the live axle, differential and half the prop shaft. Incidentally,
the units also include a reduction gearbox.

But these heavy buses plod along at low speeds in dense urban traffic,
so I don't think the unsprung weight will be nearly as serious a
problem as it would in a higher speed vehicle.