Everyone has her own definition and description of the various types and designs encompassed by this evolving form of transportation. What follows is simply our attempt at providing a structure within which to discuss and evaluate these up-and-coming electric (and partly-electric) vehicles.

First off, we should recognize that there is nothing really new going on here at all. Electric vehicles have existed since before the turn of the last century and initially out-performed those vehicles being powered by gasoline. Interestingly, many of the early electric vehicles were later used extensively by women; most often for in-town travel. Even the new so-called “hybrid” (or partly-electric) vehicles, often heralded as being “the latest advancement in electrically-powered vehicle technology” have been around for decades, just not in our garages. Case in point, the next time you see a locomotive pulling a few hundred freight cars you can rest assured that you are witnessing the power and reliability of a long-time hybrid known, descriptively enough, as a diesel-electric.

So then, having recognized that our current offering of electric vehicles are not really new but more just a long-proven idea mated with 21st century materials what is it exactly that qualifies as an electric vehicle and how do they work?

It may be helpful when considering electric vehicles to first arrange them into one of two broad categories: Pure Electrics and Hybrid Electrics. Within the Pure Electric category are the battery-powered vehicles that have no primary on-board means of generating electricity. All the electrical power must come from energy stored in the batteries themselves. Within the Hybrid-electric category are all the vehicles that do have a primary on-board source of electrical power. This on-board electrical power source could be as simple as a regular gasoline engine mated to a mechanical electrical generator, or something as exotic as a solar panel or a fuel cell.

At first the idea of mating a gasoline engine to a mechanical electrical generator just to produce electricity which, in turn, will be used to drive an electric motor which, in turn, will help drive the wheels may all seem like “much to do about nothing”. However there are great advantages even in this the most complex combination, as we shall see later.

That said, there are certainly far simpler ways to produce electricity than by mechanical means. Electricity can, for instance, be created either chemically though the use of “fuel cells” or photovoltaically, using solar panels. The direct creation of electricity eliminates the need to first convert mechanical energy into electrical energy by way of a generator, eliminating both the generator and the engine that drives it.

While simple and quiet, fuel cells still need a “fuel supply” (generally hydrogen and oxygen) to make them work. Thus even this type of hybrid-electric needs to stop to refuel. The only type of hybrid vehicle that can avoid stopping to refuel is one that is solar powered since, in effect it refuels constantly while driving. Constantly that is during the day, at certain latitudes, at certain times of the year, and under certain meteorological conditions.

Confused Yet?

We will pause briefly at this point to comment on two items that may possibly have already caused some confusion (or argument!) in the minds of our more careful readers. The first of these is the fine but important distinction between a “hybrid engine” and a “hybrid vehicle”. The second item we will examine is our decision to classify the solar-powered vehicle as a “hybrid” rather than as a “pure” electric.

As to the first item, be aware that relatively few “hybrid vehicles” utilize anything that could rightfully be considered to be a “hybrid motor” although such all-in-one “engine/generator/electric motor” combinations certainly do exist. The Honda Insight is one example. In these “hybrid-motored” vehicles the traditional engine/generator system is mechanically connected to the electric motor as well. By way of contrast, in the increasingly more common “distributed” design, the only physical connection between the engine/generator and the electric motor may be by way of high voltage wiring.

The distributed approach allows for the placement of the electric motor far away from the engine/generator. Of course, even when the engine/generator is mechanically separate from the electric motor it can still be said to be a “hybrid vehicle” even if it cannot be said to be a vehicle that has a “hybrid engine”. You may well find this to be too fine a distinction, perhaps, but one that might come in handy later.

As to the second item mentioned, that being our classification of solar powered cars as “hybrids” we can only say that we believe those who prefer to classify them as “pure” electrics do so for reasons of status and praise rather than physics. Unlike, say, solar heated water panels, solar vehicles most certainly blend two very different technologies, namely electric motors and photovoltaic panels. Not even the fact that sunlight is free, natural, and readily available can make the vehicle that it powers any less a “hybrid” given the basic meaning of that term: On-board generation of primary electrical power and an electric motor which uses it.

But enough about the finer points of electric vehicle classification! The end goal here is to create a framework within which the pros and cons of each of the various types of electric vehicles can be discussed and evaluated.

However, before comparing and contrasting these various types, it would be most productive to take a quick look at the overriding principles and the resultant operational advantages that apply to virtually any form of electric vehicle.

Off to the Races