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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default Lets have green public transport

harry wrote:
On Dec 28, 6:44 pm, The Natural Philosopher
wrote:
harry wrote:
On Dec 28, 1:22 pm, The Natural Philosopher
wrote:
tony sayer wrote:
In article , Doctor Drivel
?@?.? scribeth thus
"tony sayer" wrote in message
...
In article , Doctor Drivel
scribeth thus
"dennis@home" wrote in message
b.com...
"funkyoldcortina" wrote in message
...
That's not true for the Prius. You still get better mpg than a
conventional petrol car on motorway trips, as once you're up to speed
you
can ease off the pedal and the electric motor does most of the work to
keep you at-speed, requiring much lower power output from the engine.
Well that's plain rubbish.
If the electric motor is doing the work then it has to get its energy
from
somewhere.
It can't be the battery or it would go flat.
Engine braking and wheel braking put energy back into the battery
reclaiming
otherwise wasted energy. The Prius is old hat now - 1997. The Volt and
the
new Volt, Lotus/Jaguar designs are the way now.
Kinetic energy is best reclaimed using supercapacitors -
electric trains use
these.
Which ones, any in the UK?...
In Germany and experimental in UK. Some have the capacitor bank on the side
of the track rather that on the train.
And just how many kilowatts hours does one of they hold then?..
think watt seconds.
They are power factor correction devices.
The trains run off AC. capacitors store DC only..- Hide quoted text -
- Show quoted text -
They would hardly be power factor correction devices mounted on the
trackside.

Why not?

Its a lot better than in the trains..they are heavy..- Hide quoted text -

- Show quoted text -


They would be close to the motors to reduce current transferred
through the pantograph.

That is predicated on you thinking they are batteries there to assist
acceleration.

They are not. They are PF correctors there to reduce losses down the
overhead wires.