Another question was brought up to me,
What cools the electric motor? Electricity generates a lot of heat, doesnt it?

In the Insight, since the motor is mated up to the Internal Combustion Engine, they are both cooled by airflow directed through the engine compartment. I know there is a heat sink but I don't see any additional fan, etc for the electric motor.

edited to add: Of course the ICE is mainly cooled by the typical water cooled system found in non-hybrid cars, too.

I can take a stab and say that regeneration helps control some of that heat, but honestly I haven't the faintest.

atleast in the prius, its on its own water cooling system w/ the PSD (power split device)

I'm not sure that that is the case. From my understanding regeneration is mechanically driving the electric motor using the momentum of the car which results in the spinning of the armature generating electricity. This is merely the reverse of the process used to drive the electric motor in the first place. When the motor is driving the car resistance in the wire is (I think) the primary heat producer (working on the same principle as an electric heater). The same resistive losses that produce heat when the motor is driving the car will be present when the motor is used to slow the car. If anything regeneration will increase the heat load on the motor.

Regeneration will decrease the load on the breaks however.

According to This Link the elctric motor is water cooled.

Christian

by water-cooled we mean coolant, correct?

Yep.

The coolant is water that circulates probably in pipes around the electric motor. In wintertime you add antifreeze to the water and it becomes a mixture (A side note: antifreeze is not a good coolant all by its self and that's why you have to make sure there is still enough water in the mix).

The water is then cooled by radiators in the front of the engine by the air blowing through them. The air is either blown through by the motion of the car or (in the prius) fans driven by electric motors.

The other option is an air-cooled engine where the engine is cooled directly by air blowing over the engine. Most cars these days are water cooled.

Christian

water itself isn't good for cooling either... you'd need the antifreeze to keep the boiling point higher

and the freezing point lower...ah, the wonders of coligative properties.