How to Go Green: Hybrid Cars


Photo credit: romana klee/Creative Commons

[by Michael Graham Richard]

Everyone knows that our automotive way of life has had a massive impact on the environment. Better public transportation, getting more people on bicycles, and carpooling and car-sharing all have their place in making the world a greener place, but the transition to a green utopia where we're whisked through tubes and dropped delicately at our destinations without emitting a single molecule of CO2 isn't going to happen overnight. For now, most of us need (and many of us love) our cars - not to mention the open road and all that is good about driving.

Hybrid cars are, of course, playing a large part in the current era of the green transportation revolution. In the past decade, they've gone from avant-garde curiosities to mainstream objects seen in parking lots everywhere. Most people associate the term "hybrid" with better gas mileage and lower emissions. And while it's true that most hybrids are better for the environment than their traditional counterparts, not all hybrid vehicles function exactly the same way. In this guide for How to Go Green, we take a look at how different hybrid vehicles work, provide tips for buying a new hybrid car, and even show you how you can drive a little greener.

Understanding the Different Types of Hybrid Cars
By definition, a hybrid vehicle uses more than one source of power to move around. Currently, all commercially available hybrid cars are gasoline-electric hybrids. But there are different types of hybrid cars - ;full, assist, and mild hybrids - that work in different ways to achieve various goals with varying environmental benefits and effects. Key differences between varieties of hybrids are defined by the differences in their drivetrains; there are also cost differences between the different systems. Following is a primer that will bring up to speed.

Full Hybrids / Strong Hybrids
The defining characteristic of these cars is that they can run on either just the gasoline engine, or just the electric motor. They can also run on a combination of both. Examples of full hybrids are the Toyota Prius, Ford Escape Hybrid, and Nissan Altima Hybrid
Assist Hybrids / Power Assist Hybrids
These cannot run on the electric motor alone. The electric motor is used as a way to "boost" the gasoline engine, as well as to allow regenerative braking and stop-start capabilities. Examples of assist hybrids: Honda Civic Hybrid, Saturn Aura Hybrid.

Mild Hybrids
Mild Hybrids have drivetrains similar to regular cars, with beefed up starter motors that allow them to turn off the engine to save gas (while stopped at a red light, for example) and to restart the engine very quickly when needed. An example of mild hybrid is the Chevy Silverado Hybrid.


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Top Green Hybrid Car Tips



  1. Educate yourself.
    To be a conscious buyer,you first need to educate yourself about the various kinds of hybrid cars (remember, that's full, assist, and mild hybrids) and take a good look at the real reasons you have for owning a car. The goal is to find the best match between a hybrid car and your needs and goals.

  2. Define your Needs
    If you're considering buying a hybrid car, start by creating a list of what your needs are. How many passengers do you generally carry? How much cargo space you need? What type of terrain and weather do you need to conquer most often? If you tow a boat just twice a year, for example, you might not really need towing capabilities the rest of the time. (You could always rent or borrow on those two days.) And if you transport more than 4 passengers only a few times per year, you probably don't not need a seven-seater.

  3. Define Your Goals
    Some people want a hybrid car for environmental reasons,such as maximizing fuel-efficiency and minimizing smog-forming tailpipe emissions; some for financial, such as saving money on gas and having a low total-cost of ownership. Yet others want to make a statement or "vote with their wallets" to help build a market for cleaner cars, and to help promote the technology. Whatever your reasons - and they may likely be a combination of these factors - defining your goals can help you decide which car is right for you.

  4. Get the low-down on local policies.
    Some local governments offer special exemptions for hybrid vehicles, such as free reign to drive in High Occupancy Vehicle, or HOV, lanes, regardless of the number of people in the car. Some companies also offer preferred parking for hybrids, or employee rebates. Looking into federal and local tax incentives is also worthwhile.

  5. Check Out Our Hybrid Car Buying Guide.
    So you've assessed your transportation needs, determined your environmental goals, and secured that car loan. Now it's time to get down to the business of specific makes and models. That's where our forthcoming guide for Buying Green Hybrid Cars comes in. Stay tuned for our reviews and picks that fit different lifestyles.

  6. Use the Onboard Computer to Drive More Efficiently.
    So you've purchased a hybrid car--congratulations! There's still more you can do. By adjusting some habits, and especially by using the onboard computer available in most hybrid cars (we wish all vehicles had them!), you can monitor things such as your current and past fuel economy, which can help you learn to be a more efficient driver by understanding which practices get the best (or worst) fuel economy, you can then adjust accordingly. It's almost like a game - seeing your "score" encourages you to do better.

  7. Remember That General Green Driving Tips Apply to Hybrids, Too.
    Hybrid car engines may be more advanced than internal combustion versions, but that doesn't mean you should forget about general green driving tips. Driving at a relatively constant speed as much as possible, combining trips, coasting to decelerate, keeping your tires properly inflated, removing unnecessary weight from the car (don't carry those bowling balls in the trunk permanently!), reducing aerodynamic drag (by removing cargo racks, for example), and avoiding excessive idling are all ways to help you minimize your environmental footprint -- and maximize fuel efficiency -- no matter what you're driving.

  8. Become a hypermiler!
    Hypermiling, or the act of tweaking every little thing you do to inch your fuel efficiency ever higher, is practically considered an art form by the people (known as "hypermilers"), who practice it. Perfecting the skill requires some dedication (some drivers even do it for sport) but the basic principles begin with the tips mention in tip 7, above. Put them all together, and make it your M.O. to save fuel at every turn, and before you know it, you'll be a seasoned pro hypermiling down the highway.


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Hybrid Cars: By the Numbers



  • 16,000 lbs.: Amount of money the average driver saves per year from buying a hybrid car.

  • $3,750: Amount of money you save per year from buying a hybrid.

  • 22: Number of hybrid vehicles on the market that have a lower total cost of ownership than their conventional counterparts over a five year/70,000 mile period.

  • $13,408: Amount of money the Toyota Prius saves consumers over a similar-size sedan that is not a hybrid.

  • 40 mpg: Average fuel efficiency of new vehicles by 2020 that manufactuerers currently have the techonology to create by improving conventional engines.

  • 2010: Year Federal tax credits on hybrids are available until.

  • 60 mpg: Fuel efficiency of the 2007 Toyota Prius sedan in city driving as rated by the U.S. Environmental Protection Agency.

  • 50 mpg: Average fuel efficiency of the hybrid version of the Honda Civic.

Sources: NRDC, StopGlobalWarming.org, TreeHugger.com
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Green Hybrid Cars: Getting Techie

Here are a few technical details that you don't need to know about to buy a hybrid car, but that you might still find interesting. These technologies are not exclusive to hybrid cars, though you will rarely find all of them on a non-hybrid. We do wish they were more common, though. For example, if more vehicles had a stop-start system and low-rolling resistance tires, vast quantities of pollution would be avoided.

Continuously Variable Transmission
If you are like most drivers, especially in North-America, there's a good chance you've never driven a car with a Continuously Variable Transmission (CVT). Unlike manual and automatic transmissions, the CVTs used in most hybrid cars (and a growing number of non-hybrids) don't have a set number of gears. Operating a CVT vehicle is a unique experience, and although driving one might seem weird at first, it will soon become second nature. If you give it a chance, you'll find that the CVT is smoother and more efficient. Its design allows for an infinite variability between the high and low gear ratios, so it can keep the engine near the most efficient RPM while smoothly shifting the transmission to accelerate or decelerate.

Regenerative Braking
To power their electric motors, hybrid cars need to keep their batteries charged. They can do this in two ways: by using the gasoline engine as a generator, or by capturing energy that would otherwise be lost as heat when braking. They do the latter by using the electric motor as a generator. During deceleration, instead of using the brake pads, the hybrid car will use the resistance created by that generator to slow down the car, generating electricity that is then stored in the batteries. This is one of the reasons why hybrid cars get better fuel economy in the city than on the highway: All those stop signs and red lights help recharge the battery.

Stop-Start System
When a car is idling at a red light, it is getting zero miles per gallon. Hard to get more wasteful than that! Hybrid cars solve that problem by shutting down the gasoline engine when the car is stopped. That wouldn't be much fun if the restart was as rough as in a regular car, but hybrids have over-sized starter motors that allow them to smoothly and instantly re-start the gasoline engine as soon as the driver takes his or her foot of the brake pedal. This doesn't make much difference on the highway, but it is a big help in city driving, helping increase fuel economy, and also improving air quality.

Low-Rolling Resistance Tires
According to the U.S. Department of Energy, between 5% and 15% of the fuel burned in a typical car is used to overcome rolling resistance. Low-rolling resistance tires are simply tires that are designed to minimize the effort that the vehicle's engine has to deploy to make them roll. This is a bit like the difference between an under-inflated tire and a well-inflated one. Most hybrid cars are equipped with them, and according to the Union of Concerned Scientists, they "meet the same federal standards for treadwear, traction, and temperature resistance as regular tires."

Plug-in Hybrid Cars
The next generation of hybrid cars will be "plug-in" hybrids. Two things separate them from the current type of hybrids that you never have to plug in: a longer all-electric driving range, and the ability to not only recharge the battery both from the gasoline engine and from regenerative braking, but also from plugging the car into an electrical outlet. This might seem like a small difference, but in practice, it can mean huge fuel economy benefits. For example, if you drive a plug-in hybrid with an electric range of 40 miles, and on the average day you drive less than 40 miles, you will not use a drop of gasoline and the car will act just like an electric car. It's only for trips longer than 40 miles that the gasoline engine would turn on.

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Where to Find and Buy Hybrid Cars



  • Cadillac Escalade Hybrid

  • Chevrolet Tahoe Hybrid, Malibu Hybrid (limited availability), and Silverado Hybrid (limited availability)

  • Chrysler Aspen Hybrid (coming fall 2008)

  • Dodge Durango Hybrid (coming fall 2008)

  • Ford Escape Hybrid

  • General Motors Saturn AURA Hybrid, Saturn VUE Hybrid, plus Chevrolet models mentioned above

  • GMC Yukon Hybrid

  • Honda Civic Hybrid

  • Lexus GS Hybrid, LS Hybrid, RX Hybrid

  • Mazda Tribute Hybrid

  • Mercury Mariner Hybrid

  • Nissan Altima Hybrid

  • Saab 9-X BioHybrid

  • Saturn AURA Hybrid, VUE Hybrid

  • Toyota Camry Hybrid, Highlander Hybrid, and Prius


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Green Hybrid Cars: From the Archives



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Further Reading on Hybrid Cars


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