Why drive a hybrid? Coast into fuel efficiency with sustainability expert Richard Freudenberger.

Five years ago, if you could bring up the term "hybrid" d not invite blank stares, you were probably by the d rack at your local agricultural supply. But today, hybrid electric vehicles--HEVs, or more precisely, gas-electric hybrid vehicles--are so popular that in some states there is a four-month wait for delivery, and used-car prices can exceed the manufacturers retail price in a tight market.

What happened? And how have hybrids become the answer that no one was looking for? In 1997, when the Toyota Prius was first introduced to the Japanese market, the company sold 300 cars. By June of 2006. that number worldwide had shot to over 500,000 units.

Much of the interest was sparked by ever-rising fuel costs, and, of course, there has always been a core group of enviromnentally-conscious consumers who would support anything designed to reduce the automobile's impact on the planet. But those sales figures reinforce what automakers had hoped would happen: that the hybrid technology has proven itself in the marketplace through reliability and recognition.

Hybrid-electric technology in itself is nothing new: submarines and locomotives have used it through most of the last century. But it wasn't until the advent of compact computerized components--assembled at a cost the average consumer could afford--that a mass-produced hybrid vehicle could be viable.

The concept, at least, is simple: gas-electric hybrids use an electric motor in addition to a conventional gasoline engine. The electric drive aids in acceleration, so the gas engine need not be so large, thereby reducing fuel consumption and increasing overall efficiency. What's more, the battery that powers the electric motor is set up to receive and store kinetic energy normally lost in braking, considerably reducing the stop-and-go losses of urban driving. In some hybrids, the electric drive can take over altogether at city speeds, so the gasoline engine can shut down completely. And during deceleration and traffic stops, when the foot is off the accelerator, the engine shuts down as well, eliminating wasteful idling losses,

So, manufacturers have, in one neat package, joined the best of both worlds: the clean, green electric vehicle with its silent drive and zero emissions meets the gasoline car with unlimited range and versatility. A hybrid never has to be plugged in, and the batteries are unobtrusive and expected to last the life of the car without replacement.

Toyota's Prius may be the most well known hybrid on the block. It is the most energy-efficient family sedan in North America (with a city/highway fuel economy rating of 60/51 mpg), while seating five in comfort with storage space to spare. Toyotas synergy drive uses sophisticated algorithm software to control the interaction between the gasoline and electric systems, giving the vehicle its renowned urban-driving fuel economy.

But the Prius is far from the only hybrid car available. If you can do with seating for two--which many commuters and single people can--Hondas teardrop-shaped Insight offers an average fuel economy of 63 mpg, along with an aluminum body and the lowest aerodynamic drag in the industry. Its fuel-sipping 1-Liter gas engine combined with a 14-horsepower electric motor is more than adequate to propel the 1,825-pound car, even with air-conditioning.

If you're an occasional off-pavement boonie type who'd really benefit from an SUV but can't abide the message it sends, there's always the Ford Escape Hybrid or the larger Toyota Highlander Hybrid Both come in 2WD and 4WD versions, with average fuel economy ranging from 29 to 31 mpg in the all-wheel-drive models. The Lexus RX 400h is also an HEV, with the 4WD version delivering EPA-rated city/highway economies of 31/27 mpg. Pickup trucks are not out of the loop, either. The Chevrolet/GMC Silverado (Sierra) Hybrids offer big-truck capacity with at least a nod towards fuel economy, with an average mpg rating of about 20 mpg.

And the list goes on, with the Honda Civic and Accord in HEV mode in this years offerings. The 2007 lineup is slated to include a Nissan Altima hybrid, and Toyota Camry and Sienna minivan hybrids, Chevy Malibu and Tahoe/GMC Yukon hybrids, and a Saturn VUE HEV.

Yet fuel economy is only one aspect of the hybrid Story. When you factor in environmental impact while driving, HEVs shine. Greenhouse gas emissions such as carbon dioxide (C[O.sub.2]), nitrous oxide (N[O.sub.x]), and Methane (C[H.sub.4]) all contribute to environmental pollution, and the smaller, cleaner engines available in hybrid-electric vehicles simply do not create the volume of gas emissions comparable to a conventional car. The average vehicle produces several times its own weight in emissions each )ear, mainly because of the fact that the carbon in the fuel combines with oxygen in the air once it's burned. Advanced Technology-Partial Zero Emissions Vehicles (AT-PZEVs) such as the Prius are engineered to achieve a 90-percent-reduction emissions standard. (Other vehicles, both hybrid and conventional, are also available as PZEVs, though not in all regional markets.)

Much has been made of the life-cycle cost of owning a hybrid car. and depending upon the source, the conclusions are ... well, inconclusive. Yet even in a simple analysis, when fuel savings and tax credits are factored in, the financial incentive for owning a newly purchased Prius compared to a similar-sized and priced conventional car--say a Pontiac Vibe--is considerable. At $21,725. the base price of a 2006 Toyota Prius is close to that of a similarly equipped FWD Vibe at 520,895. If you're a smart consumer and keep )our car for ten years (a long time, but a better investment) you'll probably put 160.000 miles on it--a reasonably safe milestone, even for an average car. In that period, you'll have spent $8,072 on fuel for the Prius and $15,999 for the Vibe, based on average EPA mileage figures and the national average fuel costs at this time. When you've subtracted the $3,150 federal tax credit for new-Prius buyers, it becomes clear that the HEV is a far better buy in the long term, with a lifetime savings of $10,247.

The tax credit will vary, depending on which HEV you buy: for 2006 and 2007, the credits range from $250 to $3,150, and each manufacturer has a quota. Some hybrids are so moderate in their technical approach that they do not qualify; a 45-mpg threshold has been set for hybrid vehicles. If you lived in Oregon or Colorado. you would also be eligible for state tax credits of up to $1.500 and $3,434 respectively, and sixteen other states offer some type of hybrid-buyer incentive such as free parking at marked meters or solo use in high occupancy vehicle (HOV) lanes.

There are other considerations involved in buying hybrid, most positive: the time between scheduled oil changes is twice that of a regular car, and because of the regenerative braking system, brake wear and replacement is reduced significantly. It's also possible to get a reduction in insurance premiums from some carriers for driving a hybrid vehicle. One issue that remains unresolved (because HEVs haven't been around long enough) is batter} life. Both the Prius and Ford Escape offer an eight-year/100K-mile warranty on the traction battery, and to date only a few batteries have been replaced. In California, the warranty has been bumped to ten years to meet the state's AT-PZEV requirements for those cars. Suffice it to say that neither manufacturers nor consumer advocacy groups anticipate early failure of the batteries, and most are expected to last well beyond the warranty period.

With the choices among HEVs growing, there's little reason to delay the purchase of a hybrid if you're in the market for a new car. In fact, with the current quota system for tax credits in place, the earliest buyers are the ones who stand to receive the greatest benefits.

Resources:

AAA Daily Fuel gauge Report: www.fuelgaugereport.com

EPA Fuel Economy Guide: www.fueleconomy.gov

American Council for Energy-Efficient Economy: www.aceee.org

Union of Concerned Scientists: www.hybridcenter.org

USDOE Hybrid Electric Vehicle Battery & Fuel Economy Testing: avt.inell.gov/pdf/korner.pdf

Internet Auto Guide: www.internetautoguide.com/reviews

Richard Freudenberger is a co-founder of BackHome magazine in Hendersonville (www.BackHomeMagazine.com) and was a technical editor and Research Director at the original Mother Earth News. Besides publishing a magazine, he works with book publishers in North America and the UK on renewable energy and green building projects.