Hybrid Transit Buses

Taken from Hybridcenter

Hybrid transit buses are starting to catch on with transit agencies around the country. But what’s the real story with these buses? Are they really cleaner and more fuel efficient than their conventional diesel counterparts?

Under the Hood & Around the Nation

Hybrid bus technology is similar to that used in hybrid cars and trucks, with options for both parallel and series drive train designs. These buses employ similar technology including regenerative braking, electric motors, and battery storage. One main difference is that most hybrid buses are coupling diesel-fueled engines with electric motors instead of the typical gasoline-electric hybrid configurations available in light duty vehicles. Maximizing the benefits from these buses requires optimizing the hybrid system for the transit bus routes, which might be affected by the terrain the bus travels or whether the bus frequently travels at freeway speeds or stays on city streets.

The majority of hybrid transit buses are currently being manufactured by three companies; General Motors(GM) Allison transmission, British Aerospace Engineering Systems, and ISE corporation. GM is planning to use the same technology from their hybrid bus to make their first real hybrid, a pickup to be offered in 2007. Hopefully the ability to share technology across vehicle types will allow them to keep costs down and compete with Toyota (though it is not clear that GM is so confident). Transit agencies in New York City, Seattle, San Francisco, and other cities around the country are investing in hybrid diesel buses, which promise to be more fuel efficient and lower emitting than conventional diesel buses.

Hybrid Bus Emissions

As with other hybrid technology used in cars and trucks, there is a perception that hybrid buses not only save fuel, but inherently are cleaner than their non-hybrid counter parts. As we have previously noted on HybridBlog, hybrids can have lower emissions, but they don’t automatically come that way.

The same goes for hybrid transit buses. A recent study by the University of Connecticut measured the particulate emissions from two hybrid transit buses and two conventional diesel buses in over-the-road tests. The researchers found no decrease in particulate emissions from the hybrid buses compared with the conventional diesel buses. Of course, this would be much less of an issue if the buses were equipped with diesel particulate filters that can reduce particulate emissions by more than 85 percent. Diesel particulate filter technology can be employed on both conventional and hybrid diesel buses.

Studies have shown lower emissions of nitrogen oxide (NOx) and other smog-forming emissions from hybrid buses than conventional diesel buses in full chassis dynamometer testing. However, the current Environmental Protection Agency (EPA) emission certification method is based on bench testing the diesel-fueled engine only and does not account for the bus configuration and the full benefits of the hybrid drive system. As an interim solution, California is crediting hybrid diesel buses with a 25 percent NOx emission reduction over the engine certification values. Until a proper certification method is established, emission comparisons of hybrid buses will continue to be difficult.

Fuel Economy: Potential Promise, but Questions Still Remain

The fuel economy of hybrid transit buses is all over the map, but all are improvements over conventional technology. There are reports from transit agencies of fuel economy improvements of 10 percent all the way up to 50 percent, depending on variables such as series or parallel hybrid design, system optimizations, and the type of bus route. Some over-the-road tests are being carried out by the National Renewable Energy Laboratory (NREL), but final results have not yet been released. However, preliminary results are promising with fuel economy tests showing a 25 percent to 50 percent increase for the hybrid buses being evaluated, depending in part on the conventional diesel used in the comparison. (See NREL’s website for further info). The Connecticut Department of Transportation is also performing in-use testing that shows hybrid buses netting a 35 percent fuel economy improvement over their fleet average, but only 10 percent greater than a comparable conventional diesel bus. More real-world testing and data collection, along with improvements to the hybrid systems themselves, should result in better estimates of fuel economy improvements of the different types of hybrid buses.

One interesting development in the hybrid bus world is the introduction of gasoline hybrid buses. Diesels have typically been the power plant of choice for urban buses because of the extra torque diesel engines offer to haul a busload of people. Hybrid technology is enabling gasoline buses to compete in the same market because of the boost in torque the electric motor can give and the increased fuel efficiency that hybrid drive technology offers. The gasoline hybrids offered by ISE Corporation are certified to lower emission standards for NOx and particulate matter than their hybrid diesel and even natural gas counterparts.

Cost and Maintenance

How much do hybrid buses cost? Hybrid buses can cost up to $500,000, a significant increase over a standard diesel transit bus, the cost of which is closer to $300,000. Natural gas buses, a lower-emission alternative to conventional diesel transit buses, are generally $20,000 to $50,000 more than a diesel bus. Natural gas buses will likely continue to be able to meet lower NOx emission standards than even diesel hybrid buses until at least 2010 when stronger diesel emission standards go into effect.

One advantage of diesel hybrids over natural gas buses is the relative ease for transit agencies currently using diesel buses to incorporate diesel hybrids into their fleet. Adopting natural gas technology requires installation of natural gas fueling and maintenance infrastructure that is not required for diesel hybrids (though diesel hybrids may require additional training and equipment for maintenance). For transit agencies looking only to purchase a few buses, hybrids may make sense. However, for transit agencies looking to purchase a large number of buses, a closer look at the full life-cycle cost and emission benefits of hybrids versus natural gas buses is required to make sure they are not paying more money for fewer emission benefits.

A Promising, but Cloudy Future

As with hybrid technology in cars and trucks, there is potential for significant fuel economy improvements and emission reductions from hybrid transit buses. So far, the results look promising. We’ll just have to wait and see how far manufacturers can go to improve emissions and fuel economy of hybrid transit buses, while lowering the overall cost of the buses.

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Eco-friendly hybrid car unveiled

A new environmentally friendly hybrid car has been launched, although its manufacturer admits half of UK drivers know little about this type of vehicle.

The Honda car has a petrol engine supplemented by an electric motor which takes over when the car is idling.

(Picture right: Hybrid cars have a combined petrol and electric engine)

BBC Transport Correspondent Tom Symonds said sales of such cars were growing.

Of the drivers who said they knew about hybrids, more than 40% did not know that it was a vehicle which operated using a combination of petrol and electric power.

The findings were based on the responses of British drivers who were questioned by market research company TNS on behalf of Honda in January.

Hybrid cars are more environmentally friendly than standard vehicles because the integrated electric motor aids the engine by giving it a boost during acceleration in order to improve fuel economy.

It also runs the car at idle in order to minimise emissions.

In addition to this, the battery that powers the car's electric motor charges itself up with e energy recovered during deceleration.

'Fuel economy'

Honda is just one of a number of automobile firms which are working on green technology.

Toyota's top-end subsidiary Lexus was the first company to unveil a luxury saloon equipped with a hybrid petrol-electric engine.

And Toyota hopes to see worldwide Prius sales of one million a year by 2010.

Meanwhile a Ford Focus car is available which runs on bioethanol.

Bioethanol made from grain produces 65% fewer greenhouse gases than petrol, according to the UK government agency Central Science Laboratory.

Commenting on its new car, Honda said: "The result is a car that behaves like a petrol-engined car in terms of performance, emits less CO2 than an equivalent diesel and delivers mind-boggling fuel economy."

The company said its scientists and engineers were attempting to develop a car that runs on hydrogen and does not emit nitrogen oxides or carbon dioxide.

Car tax

"Car manufacturers are worried that lack of awareness is putting car buyers off hybrids, because they're seen as difficult to fill up, drive and maintain - and expensive to buy," said the BBC's Tom Symonds.

He went on: "It is hoped cuts to car tax announced by the chancellor last week will help, though a system of grants to encourage more people to buy hybrid vehicles has been delayed."

Honda's research revealed that 70% believed that the government should be responsible for encouraging better take up of environmentally friendly vehicles.

And 35% of those questioned said the responsibility lay with car manufacturers.

Less than a fifth - 17% - felt it was the driver's responsibility to reduce the environmental impact of their vehicle.

Honda said it had sold more than 130,000 hybrid vehicles worldwide, including more than 2,000 in Europe.

http://news.bbc.co.uk

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How hybrid power surprised the car industry

By Jorn Madslien BBC News business reporter

Toyota's petrol and electric hybrid model, the Prius, is more than just a car - it is a phenomenon.

And not only because it has just been voted car of the year 2005 in Europe, on top of a similar award in the USA early this year.

The car's surprise success has sparked a revolution in the car industry that is about to change forever the way the world's automotive sector operates.

"In 20 or 40 years" all the automotive group's cars will be hybrids, the man in charge of Toyota's research and development, design and product development, Kazuo Okatmoto, told the car industry magazine Automotive News Europe.

(Picture Right: How Does It Works? A hybrid car is powered by an electric motor. The motor's battery is recharged by an electric generator which is powered by a petrol engine. Since the petrol engine runs at an optimal speed, it consumes fuel in a more efficient way than traditional petrol engines. Additional power to the battery comes from kinetic energy from the wheels when the car is slowing down. The petrol engine provides extra power for the car when required)

"And it won't just be Toyota. All makers will have hybrids," he said.

Prius stars

But these are early days.

With just 8,500 sold in Europe this year, the Prius's lofty reputation has not come about as a result of it being a best-selling model.

Rather, it has risen to the pinnacle largely thanks to endorsements from the Hollywood glitterati and their penchant for political correctness.

High profile Prius drivers such as Leonardo di Caprio, Billy Crystal, Harrison Ford and Susan Sarandon have done a world of good for hybrid cars; these days everyone who is anyone want one.

(Picture Right: DiCaprio's custom did wonders for the Prius's image)

And yet, total global Prius sales reached just 43,000 last year.

Made in Hollywood

Hollywood's enormous impact on the Prius's fortunes surprised even Toyota, which has simply been unable to deliver in sufficient numbers.

So in a rearguard action, it dramatically boosted its capacity to support the sale of 130,000 Prius next year, just over a tenth of them in Europe.

Further production facilities are being prepared outside Japan, including in China where Prius production will start next year.

And the company might even start producing the Prius in California, where Hummer-driving Governor Arnold Schwarzenegger has been prompted to swear his allegiance.

(Picturte Right: "We only have one planet," says Kevin Bacon)

Last Friday, Mr Schwarzenegger held talks with Toyota President Fujio Cho about producing Prius at the car maker's Fremont plant.

Late entrants

But if the Prius' success caught Toyota unawares, the situation was much worse for its competitors, some which have no hybrid offering at all.

Several are now desperately scrambling to catch up, with Ford and Nissan both having entered into licensing agreements that allow them to use Toyota's hybrid technology.

Ford's Escape Hybrid Sports Utility Vehicle hit the street earlier this year, complete with movie stars uttering statements to enhance both their own and the car's images:

"We only have one planet," declared actor Kevin Bacon after having driven the car last April. "We have to protect this one."

(Picture Right: Lexus unveiled its hybrid SUV earlier in year 2004)

GM, which initially had little faith in the hybrid solution, arrived late at the party, though. In Europe, meanwhile, the French car makers' stop-and-go technology has some way to catch up with Toyota.

Toyota's own efforts are also impressive: earlier this year, the car maker's luxury subsidiary Lexus unveiled its RX400h SUV and soon all Toyotas will come with hybrid engine options.

The trend is clear: the supply of hybrid cars is set to rise very fast indeed.

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The gas-guzzlers versus the greens

BY Bill Garrett (BBC Money Programme)

Whether you see them as gas guzzling monsters of the road or as versatile necessities of modern life, four-wheel drives have become the most controversial cars on the road, pitting environmental campaigners against car lovers and motor manufacturers.

Now the industry is fighting back by using new technology it says will improve the green credentials of their 4x4s.

(Picture Right: Many celebrities like 4x4s - especially hybrid ones)

Cars have always attracted their share of criticism from green campaigners, but expensive four- wheel drives, with their heavy fuel consumption and high carbon dioxide emissions, have become a particular target for activists in recent months. Now a group called The Alliance Against Urban 4x4s has started a campaign against their use in Britain's cities.

On a cold early morning in January this year, members of the group took to the streets of North London to leaflet parents dropping off their children on the school run.

Mums and dads driving their off-road vehicles through the narrow streets were presented with mock school reports giving bad marks for using vehicles the protestors claim are bad for the environment.

Sian Berry, one of the founders of the group, defends the tactics of the protestors. "We have been trying to point out to parents who are taking their children to school in 4x4s that they're polluting the air and they are basically making a very irresponsible choice".

Ups and downs

But the rise of the anti-4x4 protest groups spells bad news for the car industry.

These off-roaders - known as SUVs or Sport Utility Vehicles in the States - are amongst the few growth areas for the hard-pressed motor industry, and now virtually all manufacturers, from Ford to Honda, Porsche to Land Rover, include them in their model ranges.

Demand for SUVs has doubled in the UK in the last 10 years with 80,000 sold in 2004 alone, and that accounts for over 6% of all new cars sold here.

David Motton, editor of What Car?, argues that they appeal to people's desire to make their lives feel more exciting.

"Maybe you are just on the way to the supermarket, but you might feel that if the mood takes you, you could dash off to Snowdonia.

"It just gives you a sense that perhaps life might be a bit more adventurous than the humdrum life that most of us really lead."

So the big problem for the car industry is how to hold on to this profitable and glamorous sector of the market whilst appeasing the environmentalists.

Escape to victory

Ford think they might have the answer by incorporating what is known as hybrid engine technology into some of their SUVs.

Hybrid vehicles are powered by a combination of a petrol engine and an electric motor, and the effect of this dual power source is to reduce both fuel consumption and carbon emissions.

They have now launched the new Ford Escape Hybrid in the USA, the world's first commercially-available hybrid SUV.

Mary Ann Wright, head engineer for hybrid technology at Ford, believes the company is responding to the concerns of its customers.

"We love our big bodacious SUVs, but in recent years we are not feeling quite so good about driving them because of the environmental footprint that they leave. And we are looking to create a product that would appeal to the environmentally-conscious consumer and the [Ford] Escape was perfect".

But is this a genuine effort to improve the green credentials of the SUV, or simply an attempt to make it more marketable?

Last year, Lexus, the luxury offshoot of Toyota, unveiled the Lexus RX 400h hybrid off-roader at European motor shows. It will be the first hybrid 4x4 to reach the UK market later this spring.

At a cost of over £40,000 it will be considerably more expensive than its petrol-only counterpart, but Lexus is hoping that customers will be won over both by the idea of lower fuel consumption and the concept of guilt-free 4x4 motoring.

Model behaviour

John Wormald, co-author of "Time for a Model Change", an analysis of the worldwide motor industry, argues that the industry is trying hard to balance the needs of its customers against growing environmental concerns.

"It's a classic contradiction... between the interests of the individual and the interests of society or of the global community. SUV hybrids are a way of reconciling those two conflicting interests, a way of being able to keep a larger vehicle without its being quite so thirsty and polluting."

Whatever the environmental arguments, the 4x4 is undoubtedly here to stay - the motor industry has invested too much to let it become a passing fad.

Whether the anti-4x4 campaigners can ever be persuaded that greener SUVs represent a genuine concession to environmental concerns is more of an open question.

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US prepares for hybrid onslaught

Sales of hybrid cars in the US are set to double in 2005, research suggests.

Research group JD Power estimates sales will hit 200,000 in 2005, despite higher prices and customer scepticism.

Carmakers are starting to build hybrid sports utility vehicles (SUVs), the four-wheel-drive vehicles which now dominate the US car market.

(Picture Right Above: Ford is racing to catch up on hybrids)

Hybrids cut both petrol consumption and emissions by combining a petrol engine with an electric motor constantly kept charged by extra engine power.

Several jurisdictions, notably the state of California, mandate low emissions for new cars.

Equally, the rise in oil prices over the past year has sparked hopes that consumers may be tempted by potential savings of a few hundred dollars a year on fuel.

The race is on

At the Detroit Motor Show, a range of manufacturers are prominently displaying their hybrid credentials.

Toyota has led the market to date with the Prius, popularised by a number of celebrities keen to burnish their "green" credentials.

In April it will launch a hybrid version of its luxury Lexus SUV, with a Highlander SUV due later in the year.

Honda has three hybrids on the market, and between them the two Japanese carmakers sold more than 80,000 units last year.

(Right Picture: Hollywood has taken hybrids to its heart)

Ford, which has sold 4,000 of its first hybrid since its launch in August, is bringing a hybrid SUV - the Mariner - to market a year ahead of schedule, with plans for three more models by 2008.

GM has a hybrid pickup on the market and is showing two concept SUVs in Detroit.

Even sports car maker Porsche may join the race, although it insists it is still considering whether to hybridise its Cayenne SUV.

Caution

Others remain more sceptical.

Nissan has bought Toyota's hybrid technology, but plans to bring out its first model only in 2006.

"We want to make sure we are not concentrating on one technology," Nissan chief executive Carlos Ghosn said.

"We will not be surprised by any acceleration or deceleration in the hybrid market."

Volkswagen, meanwhile, says it will focus on clean-burning diesel engines instead.

And some watchers point out that the price tag on a hybrid - upwards of $3,000 above that of an equivalent normal-engined car, and suspicion of the technology - may still cool its attraction.

"The average consumers aren't willing to pay that premium for a car they won't drive more than six years," said Anthony Pratt from JD Power.

http://news.bbc.co.uk

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Hybrid cars take hold in US

By Kevin Anderson BBC News Website, Washington

The United States - land of the brave and home of the SUV, sport utility vehicle.

But now the gas-guzzling gargantuans are being challenged by fuel-efficient, environmentally friendly hybrids like the Toyota Prius and hybrid versions of popular models from Honda.

(Picture Above: Hybrid car owners rally for energy independence in Washington)

The hybrids could one day help to reduce the United States' output of greenhouse gasses, but despite the buzz surrounding them, they still make up a relatively small percentage of auto sales.

'Prius Patriots'

Hybrids use both petrol and electric motors to double their fuel efficiency and halve their emissions.

It's a well-known fact that environmentally-minded celebrities including Cameron Diaz and Leonardo DiCaprio have bought them.

As a matter of fact, Mr DiCaprio has a small fleet of four not only for himself but also for his mother, father and step-mother.

The Washington Post called Toyota's Prius hybrid "Hollywood's latest politically correct status symbol".

But it's not just environmentally minded movie stars that are snapping up hybrids by the thousands.

Hybrid cars are one of the few things that seem to bridge the political divide in the US.

"It's a darn shame the US manufacturers didn't get on the bandwagon"
[John Andersen, hybrid car owner]

So-called "Prius Patriots" including former CIA director James Woolsey drive the cars because they see it as a strategic necessity for the US to reduce its dependence on foreign oil.

According to the Natural Resources Defense Council, the US spends $200,000 every minute on foreign oil.

John Andersen, who lives outside of Washington DC, drove his Prius in a rally last summer on the 4th of July holiday, which was billed as a declaration of independence from foreign oil.

Mr Andersen describes himself as a pro-life, religious conservative who still has to be convinced of the threat of global warming, but he loves his petrol-sipping Prius.

He loves it so much he says he will never buy another traditional car.

Depending on his driving patterns, he sometimes gets as much as 53 miles to the gallon, compared to an estimated 9.6 miles per gallon for Hummer's H2 heavy-duty SUV (based on listed range and fuel capacity).

Mr Andersen has been disappointed by US hybrid efforts. "It's a darn shame the US manufacturers didn't get on the bandwagon," he said.

A hybrid version of the Ford Escape, an SUV, achieves only 33 miles to the gallon, according to the Ford website.

US automakers say they are working hard to develop hydrogen fuel-cell technology, but Mr Andersen said the widespread use of fuel cells is still years away.

"That's what great about hybrids. They are here now," he said.

Small percentage of market

However, despite the buzz about cars like Toyota's Prius, hybrids still make up a relatively small percentage of overall car sales in the US.

Toyota plans to double the production of the Prius to 100,000 a year for the US to help alleviate severe shortages in some parts of country, where buyers must wait three to six months to take delivery.

Last year, about 80,000 hybrid cars and trucks were sold out of some 17m total sales in the US, according to David Friedman, research director for the Union of Concerned Scientists' Clean Vehicle Program.

"Hybrids are becoming a mainstream product," he said, adding that if anyone would have said five years ago that hybrid sales in the US would be approaching 100,000 per year, it would have been thought "inconceivable".

"If for every 40-mile-per-gallon hybrid sold, they sell a 16-mile-per-gallon gas guzzler, then there will be no effect from hybrids"
[David Friedman, Union of Concerned Scientists]

Mr Friedman said that Americans would have to buy 40m to 60m hybrids over the next 10 years to stall greenhouse gas emissions at 2010 levels.

"If the government continues its vacuum of leadership, nothing will happen" to address greenhouse gas emissions, he said.

The US government sets a minimum standard for fuel economy for auto manufacturers.

But the minimum applies to a weighted average across the entire line of vehicles sold by the manufacturer, and trucks and SUVs are held to lower standards.

Furthermore, SUVs designated as heavy duty vehicles like the Hummer H2 are not held to any standard.

"If for every 40-mile-per-gallon hybrid sold, they sell a 16-mile-per-gallon gas guzzler, then there will be no effect from hybrids," Mr Friedman said.

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Hybrid cars: Do they make sense for you?

Soaring gas prices and a tax deduction may sway some buyers, but if you'd rather go cheap than go green, nirvana is still a ways off.
by Des Toups

Hybrids, those fuel-sipping cars that use both gasoline and batteries but never require recharging, seem to make a world of sense as gasoline prices blow past $2 a gallon. They pollute less, they consume less, and they make you feel good. But do they make sense if you’re simply trying to save money? Not yet.

Hybrids are an expensive way to save gasoline. If you spend more on a hybrid car than you'd have spent otherwise, you're unlikely to ever get your money back -- even if you got rid of a gigantic, fuel-sucking SUV. Right now, a cheap compact is a better buy than an expensive hybrid. A couple of things could help tilt the balance for you:

• The IRS has decided that hybrid vehicles qualify for a one-time "Clean Fuels" tax deduction of up to $2,000. If you’re paying the top 35% rate, that’s $700 off your bill. This deduction applies to hybrids bought in 2004 and 2005; it's scheduled to disappear for 2006.
• A number of new hybrids -- sedans, SUVs, even trucks -- are on the way. At least one of the new models is no more costly than its similarly sized, gasoline-powered kin.

The choices

Only a true fuel miser would appreciate Honda's tiny >Insight, A featherweight two-seater with limited cargo space. At about $21,000, it's powered by a tiny, three-cylinder engine with an occasional assist from the batteries, which recharge by reclaiming the energy expended when you slow down or brake. The EPA rates the automatic version at 57 city, 56 highway, but enthusiastic owners report as much as 100 mpg if driven ultra carefully.

Sedan buyers won't get that kind of mileage, of course. The two best sellers are Toyota's Prius and Honda's Civic Hybrid. Both start around $22,000. Honda also makes an Accord Hybrid, which has a unique twist in that the power from its small electric motor is used primarily to boost performance. It's about $30,000.

Both Ford and Toyota have hybrid sport-utilities on the market, and Chevrolet, GMC and Dodge have hybrid pickups on sale or in the works.

Forgo an SUV and save a bundle

Whether or not the purchase of one of these fuel-sipping machines makes financial sense depends on the alternative. You'll save a small fortune if you opt for a hybrid over a larger sedan or sport-utility. Buy that Civic Hybrid instead of a 20-mpg Accord V-6 and you’ll see a savings of $656 a year on $1.50 gasoline, not to mention a few thousand on the purchase price. Commute in the hybrid rather than a 13-mpg sport-utility and you’d save $1,262, not to mention a tankful or two of guilt.

Apples-to-apples comparisons are less kind. A garden-variety Civic LX sedan sells for about $16,500 and returns 31 mpg in the city, 38 on the highway. Using the city mileage figure (which most people would achieve in day-in, day-out driving), you’d spend $725 a year to drive 15,000 miles on $1.50 gasoline. The Civic Hybrid would consume $469 worth, a savings of just $256 a year. (At $2 a gallon, the savings is about $342 a year.)

Without the tax deduction (and recognizing the time value of money), a hybrid owner would never earn back the $4,000-plus premium for his car. Lop $700 off the cost of the hybrid and the picture improves, but it’s still no deal. But every dime increase in the price of gasoline pulls the break-even point closer.

Some states offer incentives that sweeten the deal even further. Oregon, for example, offers dollar-for-dollar credit against state income tax up to $1,500. Maryland offers a break on sales tax. There are little perks, too: Several states allow solo drivers in these hybrid cars to use the carpool lanes, and some cities offer free parking. Check with your local bureaucrats before you buy.

Some alternatives

There are alternatives for both the economy- and ecology-minded. A Volkswagen Jetta TDI, for example, is a diesel-powered sedan that sells for $1,240 more than its gasoline-powered version, yet achieves 50% better economy. Diesel fuel economy is less fragile than that of hybrids; driving style affects them much less. Their gutsy nature is well-suited to trucks and SUVs.

Many more "clean" diesels, built to take advantage of low-sulfur fuel coming in 2006, will show up on car lots soon.

There are many traditional gasoline-powered models that are just as clean as hybrids, achieve good mileage and cost much less. The Consumer Reports-recommended Ford Focus, for example, has an engine that qualifies for Partial Zero-Emission Vehicle status, achieves 27 city/36 highway, and starts at about $13,000 -- $7,000 less than the cheapest hybrid, even before rebates.

Before you shop

It's important that drivers realize that they will have a difficult time matching the advertised fuel economy for these hybrids. Hard acceleration, cut-and-thrust driving and using the air conditioner take an even bigger toll on hybrids' mileage than they do in a regular car. Real-world economy could be as much as a third less; still, 40 mpg is pretty impressive.

Don't ignore the traditional risks behind any car purchase: You're responsible now for maintaining two power sources, not one. Hybrids have proved reliable so far -- these are Hondas and Toyotas, after all -- but their history is limited. Warranties on the hybrid-related systems are eight years, but replacing those systems after the warranty expires could cost thousands. (The battery pack in a Honda is estimated at $3,000.) And resale value is still a big question mark.

So far, resale values for the Insight have been especially disappointing compared with most Hondas. Despite a $4,000-plus difference when new, the price gap between a 2-year-old Insight and a run-of-the-mill, 2-year-old Civic LX sedan is very narrow. That's a big opportunity for hybrid-vehicle fans who don't mind forgoing the tax deduction (which applies only to the original owners) but want to pick up one of these lightweight two-seaters on the cheap.

The Prius, on the other hand, is riding a wave of consumer demand, with new models commanding thousands over sticker and used examples are maintaining their value well. Projected depreciation is less than that of the Camry, for example.

And of course, though you never have to plug one of these babies into your wall socket, there are compromises -- such as less power -- you'd do well to research. You can read more about them at MSN Autos by following the links at left.

Source: moneycentral.msn.com

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