How a Hybrid Car Works

Hybrid means a mix or fusion. In the case of hybrid cars, it refers to the employment of dual means to power a vehicle.

In 1997, Toyota introduced the groundbreaking Prius hybrid automobile. The futuristic-looking car was still powered by an engine. You still had to take it to the pump and fill it with gasoline. But something was profoundly different about this vehicle, which had managed to come out of production two years ahead of schedule. The buzz had to do with the electric motor that worked in unison with the engine, allowing for efficiency that until this point was associated only with mopeds and cars you plugged into the wall.

The press was curious; drivers were perplexed. Wasn't this still half an electric car? It had batteries, after all. So didn't it need to endure the same critical feature of the electric car: the recharge; the long power cord stretching from the car to a portable generator or electrical outlet?

But that was the key behind the new technology: A consumer now had many of the benefits of the electric car, without having the nuisances. The batteries in the Prius recharged internally. Thus, no need to hook the vehicle into a wall. Another drawback associated with the electric car―power―was also solved with the inclusion of a regular, albeit small, gasoline engine.

Much of the technology for the hybrid vehicle had been floating around research centers and hobbyists' garages for decades. Now a vehicle was finally available to the public (at least in Japan) that blew away the miles-per-gallon (mpg) averages of standard vehicles. Instead of 15 to 20 mpg, the Prius was getting in the neighborhood of 50 mpg. That was pretty close to the electric car. Plus, the emissions were greatly minimized.

Of course, during the booming 1990s, the bigger the vehicle the better―and the fact that gas was cheap made the mileage issue a moot point. Honda came out with the Insight a couple of years later, which topped 70 mph on the highway. Still, the big SUVs ruled the road.

In 2000, hybrids became available in the United States and were an instant hit, especially with the environmental crowd. The vehicles were so popular that dealerships couldn't keep them in stock―and still can't. There is generally a waiting list of up to six months before the car is delivered.

Today, things have changed, and bigger only means you will have a big hurt at the gas pump. Gas tops $3 in many parts of the country, and the demand for vehicles with better fuel efficiency could not be higher.

The Makings of a Hybrid

So what is the hubbub all about? What makes these cars so special that South Park will devote an entire episode to them (and the people who drive them)? There are two types of hybrid vehicle: parallel and series. Both essentially function on the same principles, with only slight variations. Both are equally complicated, but here are the basics.

Parallel Hybrid

This type of design involves the two means of generating power: an engine fueled from a gas tank and an electric motor supplied by batteries that generally reside under the floorboards. Both connect autonomously to the transmission, which in turn propels the vehicle. The electric motor also functions as a generator that amasses excess energy derived from the heat of braking and returns it to recharge the batteries. The power to make the vehicle function comes from two independent sources (although not necessary equally), thus you have a parallel arrangement.

Series Type Hybrid

In this setup, you have one system affecting the other. The engine (also attached to a fuel tank) in this case powers a separate generator. The generator then employs the electric motor, which runs the transmission that drives the vehicle. The generator, much like with the parallel hybrid, also gathers and stores energy from the brakes and dumps it into the batteries to keep them fresh.

How this Equates to Better Gas Mileage and Lower Emissions

There are so many factors playing a role in the hybrid's ability to achieve serious miles per gallon that it is impossible to pinpoint just one.

Engine

First, let's take a look at the engine. In your typical car or truck, an engine is just about the largest and heaviest component of the vehicle. Most vehicles are equipped with four to eight cylinders. Considering that many cars top 100 miles per hour (mph) without so much as a blink, you get the idea that these engines produce some serious oomph.

The engine in a hybrid is much smaller. For example, the Honda Insight has a three-cylinder engine that barely tips the scale at 100 pounds (a regular car engine averages 500 pounds). Along with the overall size, a hybrid engine is also constructed of lighter components. So while the total engine displacement is rather diminutive when compared with standard engines, the engine doesn't have to propel as much weight as the motor in a regular car.

One of the most interesting aspects of the hybrid and one that definitely raises the vehicle's cool factor is the automatic engine shut-off. That is, when the vehicle does not need power from the engine, it will simply power down until it's needed again.

Thus, when you come to your first red light and the vehicle seems to cut out, you just might begin to curse new technology until you push the gas pedal and instantly everything is back to normal. Besides conserving gas, the shut-off reduces the amount of emissions spewing into the air (when a vehicle idles, it tends to pollute more). In most cases, a hybrid will just shut the engine off until you accelerate again.

Frame

Notice how some hybrids look like something out of The Jetsons. This aerodynamic look is designed to create less drag. The hybrid takes it even further using lighter parts and more curving to help the small engine. And, the sides extending down over part of the back wheels masks the system that recycles energy from the brakes.

Electric Motor and Batteries

The electric motor aids the engine when it needs more power―say, for climbing or accelerating to high speeds. It has the ability to store excess energy because it also acts as a generator. It then delivers this energy to the batteries to keep them charged. This is mostly done via braking. When you press the brakes, some of the heat released is trapped as energy. This process is known as "regenerative braking." Thus, when you slow down you are storing energy that will ultimately be transferred to the batteries.

Tires

If you kick the tire on a hybrid, you might think it feels like the tires on an old Radio Flyer wagon: hard. The special design and high air pressure of the tires creates less drag, saving gas.

Are Hybrids Worth Buying?

While hybrids have plenty of advantages, there are a few things that some people might consider enough of a drawback to steer them away. So, it's always good to learn both sides so your decision is balanced.

The main dissent you will find in the consumer press and the blogosphere involves two basic issues: price and gas mileage. The first makes sense. Just browsing sticker prices of the hybrid sedans and SUVs will reveal that they cost more than many other vehicles. But, the gas mileage issue might throw people for a loop.

After all, hybrids are designed to reduce gasoline intake and to be exceptionally fuel efficient. They are―if compared to a mass of vehicles manufactured each year, especially the likes of the Hummer, Chevy Suburban, or Cadillac Escalade.

But up against other models, the mileage difference is not, these critics say, worth the price difference. For example, the Honda Civic is about $4,000 less the Honda Civic Hybrid. Yet, the mileage difference is separated by only one mile per every eight gallons. The critics conclude that it would take around four years for savings at the pump to make up the cost variable between these models.

Is there truth to this? Definitely. If you look at highway miles, the hybrid acts much like other vehicles. Hybrids burn gas. The electric motor is busy pumping energy back into the battery at that point. Where hybrids really save gas is in the city. That's when the electric motor really goes to work and when idling in traffic causes the engine to power down.

But there other things to look at, and ultimately the debate is a bit like the organic food debate. Is there really a difference? Yes and no. But, the consumer needs to measure whether the pluses outweigh the minuses. Much of this comes down to personal choice and lifestyle.

What we know is that hybrids do burn less gas. They cost more, but there are other financial incentives such as tax cuts offered from the IRS. Perhaps the biggest plus is the emissions factor. Hybrids release much less pollution into the air than a car that runs solely on gasoline.

But, is it better than, say, biodiesel or hydrogen? Well, probably not. However, while the former is really starting to hit the market; the latter appears years away. The best bet is simply to do plenty of research on all types of vehicles until you have a firm enough grasp of the pluses and minuses to make your own choice.