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MOTHER:

How would I arrive at the right battery pack for my own car?

DA:

A typical 2,500 pound hybrid electric car will require approximately 200 amps at 36 volts to run 45 mph. Using that kind of information you can arrive at the best kind of battery pack for your particular use. For instance, two banks of the 186-plate, 12-volt batteries (six batteries) has nine kwh available. It takes 7.2 kwh to go 45 miles on the open road. With this battery system you should have a good hour of drive time on the batteries alone.

MOTHER:

How does the conversion process happen?

DA:

It can happen in many different ways. The simplest modification that you can make will give you a parallel hybrid. Add an electric motor to the existing engine of a car through drive belts, install an electric clutch (much like an air compressor), and that's basically it. The original engine and electric motor run in tandem and offer considerably improved fuel economy. The disadvantage to this method is that the large gas engine has to run all the time. It would be better if you could run on either gas or electric independently of each other. The series hybrid accomplishes that. In that design (used in the truck), the small diesel engine indirectly provides the motive force of the car. In other words it drives a generator to provide electricity to the electric motor. This method has several advantages. The diesel engine can be run at a constant number of revolutions per minute matching its peak fuel economy, and the electricity the generator produces can be shunted directly to the drive motor or into a battery bank. One of the greatest things about a series hybrid is its efficiency. Very little power is wasted. Every time you are going downhill and every time you stop, you have the opportunity to turn that inertia into electricity. You see, the electric motor which drives the vehicle is also a generator. A motor and a generator are virtually the same animal as long as we are speaking about direct current electricity. And when you are slowing down, you are actually "gearing down" : This over-revs the motor, turning it into a generator that produces electricity for the batteries. If you glance at the amp meter, you actually can see electricity returning to the batteries when this happens. This is not only energy efficient, but also saves a great deal of wear on the brakes because it slows the truck down.

MOTHER:

Why did you choose a pickup for your new design?

DA:

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