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Doctor Drivel[_2_] Doctor Drivel[_2_] is offline
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Default What to use on alloy wheels?


"Adrian" wrote in message
...
"dennis@home" gurgled happily, sounding
much like they were saying:

And some modern BMWs use regenerative braking via the alternator. So
you don't even need a hybrid for that...


What do they do with the energy?
The battery should be charged by the alternator within a few seconds of
starting the engine so I doubt if it could store the energy generated.
Its probably just some marketing man telling porkies.


They run the alternator light under computer control to help save a
weensy drip of fuel. (Same with the oil pump, ffs... If that isn't a
recipe for disaster, what is?)

Then there's the stop-start of the engine in traffic, so greater battery
consumption due to more regular starting.


So probably even out at best. Chemical batteries store a lot of energy but
because of the state change, they charge and discharge slowly. A car
braking will not take all the kinetic energy. Using a supercapacitor
virtually all the kinetic energy will be clawed back, then this can be used
accelerate the car using an electric motor.