What’s an electric car?
It seems like a simple question with a simple answer. But like so many things in the automotive world, it's an answer with many shades of gray. Put in the simplest terms, and for our own purposes of categorizing the many flavors of hybrid, plug-in hybrid, electric and other “green” cars currently headed for American shores, an electric car is a passenger vehicle that is propelled solely by using electrical current to turn the driveshaft.
Now, not everyone in the automotive world might agree on this definition, because after all, isn't the much-anticipated Chevrolet Volt an electric car since it's plugged into an outlet to charge overnight?
It's a fair question, especially since the Volt will be largely propelled by electricity, but not solely – it also has a gas-burning motor that extends the overall range of the car. That's why we're putting the Volt and other gas-assisted plug-in hybrids like the Fisker Karma in the “plug-in hybrid” category, and sticking with electric-only vehicles like the Tesla Roadster and Nissan Leaf when we talk about Electric Cars.
We think it's the best way to make sure we're all on the same page, and we've got a hunch the rest of the media will be following suit once the public starts to take all these new technologies and models for their first spin around the learning curve.
So now that we know what we aren't talking about, let's get down to what really makes an electric car hum.
21st Century Electric Cars are Real Cars
Odds are you've already taken a ride on one of the most commercially successful electric vehicles ever – the golf cart. Think of today's electric cars as the inevitable evolution of that covered bench on wheels that moves you quickly and quietly over to your final putt.
An electric motor, most often run off a controller connected to rechargeable, high-capacity lithium-ion batteries (although other technologies like ultracapacitors are in research and development for use in cars) propels the car on its own.
The controller is key to creating the smooth, silent ride that is distinctive to electric cars. The controller is essentially a box that translates gas pedal pressure into acceleration. Press hard on the pedal, you go faster. Depress the pedal and you slow down.
Battery packs in the Nissan Leaf
The electric car engine design is actually far more simple than a basic gas-propelled car because it eliminates the need for a transmission, exhaust system and all the other cumbersome parts tied to combustion.
However, getting rid of the engine does create a need to replace some of the secondary systems that run off of it with small motors to power things like the water pump, air conditioner, power steering and power brakes. But overall an electric car has far fewer parts that can break down or require maintenance. Some argue that mechanical simplicity will likely result in electric cars being less expensive to maintain. Only time and real-world ownership of electric cars will reveal the answer to that opinion.