HYBRID VEHICLES

After owning and driving a hybrid automobile for a year, I want to share my observations.

Many hybrid cars are not much more than golf carts, and ideal only for commuting. However, there are some mid-sized hybrids out there – mine is a Toyota Camry. It’s not a Cadillac by any means. But it is more than adequate, and is as good as most vehicles for those longer trips.

For those of you unfamiliar with hybrids, let me point out that they have an electric motor that runs off a high voltage battery in addition to the gasoline engine which powers the car. What you may not realize is that the electric motor and battery are comparatively minimal. Their job is pretty much limited to soaking up energy when the traffic signal turns red and giving it back when the light turns green. All power originates in the gas motor. The electric side of things merely lets the vehicle recoup small amounts of energy lost during braking, improving city fuel economy.

However, Toyota did things differently. They implemented the electric motor is such a way as to achieve a continuously variable speed transmission. Yes, that’s right. My Camry does not shift gears. The gas engine is connected to the drive wheels through a planetary gear that is also connected to the electric motor. Thus the gear ratio of the gas engine is determined by the RPM of the electric motor, which is computer controlled.

The result of this scheme is powerful smooth acceleration all the way up to the point the computer says you are going fast enough (>112MPH, where many cars quit). Passing performance is impressive – even going uphill. Alternately, when you are just cruising along the gear ratio is optimized for fuel economy. The bottom line is that fuel economy is optimized regardless of cruising uphill or down, with a headwind or tailwind. But when you floor it, you have the maximum acceleration possible because that results in the engine being wound up tight until you reach the max vehicle speed – or when, if you have any brains at all, you back off.