Hybrids get better mileage in the city than highway because the mechanical energy from braking is used to charge the battery. Are there any gas vehicles where they have used this braking energy for anything?
Regenerative braking requires the presence of a load along the power train that can be applied to convert the kinetic energy of the mass into potential energy of some kind, such as electric potential or a mechanical spring. Also, the kinetic energy of the car could be converted to a spinning mass, such as a flywheel.
I believe some buses in the 1950’s were engineered to use a flywheel to store the energy of the wheels and return that energy when accelerating from a stop, but no contemporary commercial cars use that means.
As far as I know, the only method used nowadays for converting the kinetic energy is to use the drag of an electric motor in the drivetrain. If you have an electric motor in the drivetrain, you basically have a hybrid vehicle.
BTW, the hybrids that get better mileage in the city do that through greater use of the electric motor when the gasoline engine is not running, which maximizes the efficiency of the electric motor / gasoline engine system. Only a small proportion of the increased mileage is due to regenerative braking.
Regenerative braking requires the presence of a load along the power train that can be applied to convert the kinetic energy of the mass into potential energy of some kind, such as electric potential or a mechanical spring. Also, the kinetic energy of the car could be converted to a spinning mass, such as a flywheel.
I believe some buses in the 1950’s were engineered to use a flywheel to store the energy of the wheels and return that energy when accelerating from a stop, but no contemporary commercial cars use that means.
As far as I know, the only method used nowadays for converting the kinetic energy is to use the drag of an electric motor in the drivetrain. If you have an electric motor in the drivetrain, you basically have a hybrid vehicle.
BTW, the hybrids that get better mileage in the city do that through greater use of the electric motor when the gasoline engine is not running, which maximizes the efficiency of the electric motor / gasoline engine system. Only a small proportion of the increased mileage is due to regenerative braking.
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