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Advantages And Disadvantages Of Hybrid Cars Essay

If you listen to the makers, hybrid cars are the best invention since sliced bread. While there are many reasons to buy a hybrid car, including a new tax incentive for US owners, it helps to have a good understanding of how they work. This article explores the myths, benefits and drawbacks of owning one of these new “green” vehicles.

First off: What is a hybrid car? Basically, it’s a normal, fuel efficient car that has two motors - an electric motor and a gasoline powered motor. It also has a special system to capture braking energy to store in an onboard battery.

Why a hybrid? Why not a straight gas or electric powered car? After all, one of the basic rules of science is the more complex the system - two motors instead on one - the more often it will break down. This is the main reason many boat owners prefer one motor instead of the “double trouble” of two - despite the obvious safety advantages. This is a hard question and, in the minds of some experts, not fully answered.


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The reason for two motors is in the strengths and weaknesses of both types. Specifically, electric motors use no energy during idle - they turn off - and use less than gas motors at low speeds. Gas motors do better at high speeds and can deliver more power for a given motor weight. That means during rush hour stop and go driving, the electric motor works great and, as an added benefit, does not produce any exhaust thus reducing smog levels. At higher speeds - above 40 mph - the gas motor kicks in and gives that peppy feel so many car owners look for when driving on the highway.

Another benefit of having the gas motor is it charges the batteries while it’s running. Many an electric car owner has been stranded just out extension cord range of an outlet. Hybrid owners can forget about this annoyance; the gas motors starts automatically when the battery gets low and proceeds to charge the battery - a hybrid never needs to be plugged into an outlet. Of course, if you forget to fill the tank…. Still, you can carry a gas can a half mile while a tow truck is necessary in a straight electric car.

All this new technology comes at a price: a hybrid car is complex and expensive. It has two motors and all the ancillary systems to manage them plus a heavy battery and a regeneration system used to produce electricity during breaking.

All of these systems must work together, adding complexity. While cars and, just as importantly, the computers that control them, have become more reliable, they still suffer from failures. So owners of hybrids can expect more time in the shop and larger repair bills.

Hybrids are the most gasoline efficient of all cars - they typically get 48 to 60 mpg (claimed). Not bad, but only about 20% to 35% better than a fuel efficient gasoline powered vehicle - like the Honda Civic, for example, that gets 36 mpg. But, when comparing prices - hybrids cost from $19,000 to $25,000 and gas saver cars cost $14,000 to $17,000 - the justification to buy becomes less clear.

Indeed, the difference in average annual fuel bills - $405 for a Honda Insight versus $635 for a Honda Civic - means you may never recoup the added initial cost of a hybrid. Over a ten year period owning a hybrid will save you only $2,300 - less than the cost difference for comparably equipped cars.

Much of the fuel efficiency comes from improvements in aero dynamics, weight reduction and, the biggest change: a smaller, less powerful gas engine. In fact, any car will get substantially better mileage just by reducing the engine size. The main reason this is not done has to do customer demand - they want the extra power and zippiness.

Divers find that real mileage from hybrids is actually about 10% less than claimed. When consulting manufactures web pages for mileage tips, they list the same ones that would give better fuel economy from any car: drive slow, no jack rabbit starts, etc...

But hybrid cars offer more than just great fuel economy, they offer many green advantages as well. Even a small increase in fuel economy makes a large difference in emissions over the life of the car. Also, in large cities were pollution is at its worst, they make an even larger difference since they produce very little emissions during low speed city driving and the inevitable traffic jams.

While the US has just started producing hybrids, the Japanese are the recognized leaders. Honda and Toyota are the two largest producers with the Insight and Prius. US car makers are well behind. In fact, during recent introduction of a new hybrid by GM - the Mercury Mariner, they admitted they had to license over 20 separate technologies from the Japanese. US car makers still specialize in SUVs and trucks - Ford has even introduced a hybrid version of its popular Escape SUV.

Industry analysts say US hybrids are just token models - not a serious attempt to get into the market. The reason for hybrid introduction has to do with Corporate Average Fuel Economy (CAFE) regulations. Current standards mandate that average mileage of the fleet of cars sold by an automaker should be 27.5 mpg. This means that if an automaker sells one hybrid car that gets 60 mpg, it can then sell four less efficient cars - like SUVs and trucks - that only get 20 mpg.

With only a marginal savings on gasoline and a much higher initial cost, hybrid builders are relying on two main factors to sell: the “green” image and the “new” technology. Any marketer will tell you that “new” and “green” are good for any sales.

To offset perceived reliability problems, makers are offering strong guarantees: The Honda Insight has an eight-year/80,000-mile warranty on most of the power train, including batteries, and a three-year/36,000-mile warranty on the rest of the car. The Toyota Prius has an eight-year/100,000-mile warranty on the battery and hybrid systems and a three-year/36,000-mile warranty on everything else.

The motors and batteries in these cars do not require maintenance over the life of the vehicle. The engine doesn't need any more maintenance than in any other car. Because hybrids have regenerative braking, brake pads may even last longer than those in normal cars.

But what’s a smart car buyer to do? Are the savings in gas worth the extra headaches and higher cost? Maybe, it depends on how you drive. If you drive mostly in the city, you may save enough to warrant the extra cost. Remember the gas motor turns on to charge the batteries if you use the electric motor all the time which offsets some of the advantage. Heavy long-distance commuters and lead footers will see fewer savings.

Then, there is always the environment - always worth thinking about. A hybrid cuts emissions by 25% to 35% over even the most fuel efficient gas powered models.

The tax incentive in the U.S. is another powerful motive - it can reduce your cost up to $3,400 depending on the cost of the vehicle. Better act fast, however, to get the model you want: the tax break only applies to the first 60,000 vehicles produced yearly by each manufacturer. Toyota’s Prius, for example, will quickly reach that number of sales before year-end.

Experts think in the end, hybrids are probably a transition technology. Hydrogen or methane fuel cell powered cars are probably the cars of the future. As for the environment, there are many ways to reduce emissions - using public transport, car pooling, riding a bicycle and even walking. Even just buying a smaller, fuel efficient car makes a big difference. So, think about what you are really trying to accomplish before buying a hybrid - don’t just throw your hard earned dollars at new technology for its own sake because it may be fashionably “green”.

By Philip Dunn, Copyright 2006 PhysOrg.com

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My wife and I thought we were doing well with our Subaru wagons since we had avoided the purchase of a gas guzzling SUV. Our “Subies” are fun to drive, hold lots of stuff, and usually see about 22 miles to the gallon.

Nevertheless, our Outback was starting to get up there in miles and was generating repair bills that were uncharacteristic for a Subaru. Being fascinated with hybrid technology, we finally decided to take the plunge and replace the old Outback with a newer hybrid.

We carefully weighed the arguments for buying a new vs. used car. We realized there weren’t any reasonably equipped new hybrids for less than $20,000, so we settled on a loaded 2007 Prius in pristine condition. Here is what we learned.

Benefits of Hybrid Cars

1. Hybrid Cars Show You How to Drive Efficiently
Just like a Jeep is in its element when driven off-road, and a Ferrari likes to be driven like a race car, a hybrid desperately wants to be driven efficiently. Our Toyota Prius, like most hybrids, has a display that shows our present mileage as well as average miles per gallon. It even tells us how much energy we recoup with the brakes.

All cars get better mileage when you accelerate and brake gently. But with a hybrid, you can see it, especially when you accelerate gradually enough so that only the electric engine is used. Normally I love to drive fast, but I’ve discovered myself unexpectedly enjoying the challenge of driving efficiently.

2. You Can Beat the EPA Mileage Estimates
Our goal was to double our observed fuel economy from the 22 mpg we had been getting with the Subaru. While we would have been happy with 44 mpg, or even the EPA rating of 48 mpg in the city, we were astonished to regularly see our fuel efficiency in the mid 50s. We credit efficient driving, aided by the Prius display, as the key to beating the EPA mileage estimates.

3. Hybrids Love the City
Hybrids are unique in that their EPA mileage ratings are actually higher in the city than they are on the highway. Our Prius is perfectly suited to my wife’s daily commute in stop and go traffic. Every time you stop, it generates more electricity which can then be used at lower speeds, or for accelerating quickly. It is in town where we see our mileage jump above 50 mpg.

4. Hybrids Have Multi-Engine Power
As a pilot with a sport pilot license, I appreciate the difference between a single engine airplane and the power of a multi-engine craft. The Prius is no hot rod, but, unlike a Ferrari, it actually comes with two engines. Its small gasoline engine is complemented by a powerful electric engine. Electric engines produce all of their torque from 0 rpm (revolutions per minute), a feature that allows the Prius to really scoot through an intersection from a stop. It is kind of like the snap you feel in your wrist when you operate a powerful electric hand tool.

5. It’s Eerily Quiet
Starting this car is about as much of an event as turning on a light switch. When the car begins to move, it is so silent that you are confused into thinking it is rolling downhill by itself. This is because the gasoline engine isn’t running and the electric engine is noiseless.

6. The Car Stays Warm
Mechanics will tell you that when you start an engine cold, it is harder to crank and produces more engine wear than when you start one that’s already been warmed up. In researching the Prius, I learned that it prevents cold starts by storing coolant in the equivalent of a thermos. This system keeps the fluid warm for up to three days. We are looking forward to enjoying easy starts and instant heat next winter.

7. No Emissions Tests Required
When I inquired about registering my car, I was told that a hybrid does not need an emissions test to be registered. Since your state’s laws may differ from those here in Denver, Colorado, check with your local DMV to see if an emissions or other test is required for registration.

8. Durability
One of the big myths out there is that the components of a hybrid will wear out and be costly to replace. Consumer Reports recently tested a 2001 Prius with over 200,000 miles; they found it still performed nearly identically to the 2001 Prius they tested new, and the hybrid battery was working fine.

9. Don’t Worry about the Battery
Every time I mentioned that I was buying a hybrid, I was warned about the battery failing. There is a popular myth that the battery is unreliable and a replacement is shockingly expensive. Consumer Reports notes that Toyota sells replacement batteries for $2,300 to $2,600. Practically speaking, if you had to replace a battery on a 10-year-old hybrid, you could pay about $500 for one from a salvage yard, just like you could if you had to replace any major component on an older car.

With that said, Toyota’s hybrid batteries and all other hybrid specific parts normally have a warranty of eight years or 100,000 miles. In California, the warranty is 150,000 miles. Moreover, there are numerous reports of the Prius being driven over 200,000 miles on the original battery. Given the strong warranty and consumer reports, I am confident we will never have to replace our hybrid battery.

10. Expect Less Maintenance
One of the neat things about a hybrid is that the gas engine is not running when you are stopped or driving slowly. It is amazing how often that happens in city driving. The result is that you are putting less wear on your engine. For this reason, Toyota only recommends oil changes every 5,000 miles, unlike my Subaru which specifies oil changes every 3,000 miles.

Its brakes should last longer too. Unless you have to brake suddenly, a hybrid regenerates electricity with a regenerative brake instead of applying the standard brakes. Since you could drive around all day without hardly using the conventional brakes, you can expect your brakes to need service far less often than a non-hybrid would. When the Prius was used in taxi fleets, it demonstrated less of a need for brake maintenance than its non-hybrid counterparts.

Problems with Hybrid Cars

1. Rising Gas Prices Equals Rising Hybrid Prices
We knew we had to pay a bit more for our used Prius due to gas prices rising. There weren’t many hybrids on the market, and they were selling fast. Some sellers were even trying to get a ridiculous premium by advertising their used cars for almost what a new one would cost! However, unless gas prices plummet and stay low for a long time, we feel we will largely make up our purchase premium when it comes time to sell our car.

2. Lower Highway Mileage
You won’t find me driving my Prius on the highway in the right lane at 50 miles per hour; I can only take the efficiency thing so far. When driven at the speed of most highway traffic, you can expect mileage in the mid to lower 40s. This is great, but there are compact cars and diesels that can achieve this kind of efficiency at highway speeds.

3. Not All Hybrids Are Equal
We also considered the very similar looking Honda Insight, but we were turned off by the fact that it is not a full hybrid, but rather a “mild hybrid.” Its gasoline engine shuts off when the car stops and it cannot run on its electric motor alone. It does not receive the fuel economy ratings of the Prius, and we were shocked to discover that its heat and air conditioning systems do not operate when the gasoline engine stops. That might be acceptable in a temperate climate, but it’s not acceptable in Colorado. A mild hybrid might get better fuel economy than a conventional car, but it won’t ever live up to the promise of a true hybrid.

4. Few Third Row Hybrids
We really wanted a larger vehicle with third row seating, but there is currently only one choice on the market. Toyota makes their Highlander Hybrid SUV with a third seat, but it is a huge vehicle with relatively poor mileage for a hybrid. Toyota recently announced they are coming out with a larger version of the Prius, but they will not offer a third row of seating in the version they plan to export to the United States.

5. Weak 12 Volt Battery
We were most surprised to discover that our Prius actually has a conventional 12 Volt battery just like any other car, in addition to the larger high voltage battery. This smaller battery provides power to the accessories, and like any other car, the Prius will need a jump start if this battery is drained. We accidentally left an interior light on overnight and couldn’t start the car in the morning – it turns out that accidentally draining the conventional battery is a common problem. Many Prius owners buy an aftermarket battery for $180 when the original one finally gives out, as the aftermarket version is reported to last much longer than the standard model Toyota uses.

Final Word

Through careful research, I was able to dispel many of the frightening myths going around about hybrid ownership. At the same time, we have no illusion that our Prius will always be perfectly reliable and maintenance free during the years we own it. What we do have is the reasonable belief, based on hard evidence, that this vehicle will be at least as reliable as a standard car while delivering more than twice the fuel economy of our Subaru.

So far, we are extremely satisfied with our purchase. Until the day we buy a full electric car, it is difficult to imagine there will be a time when at least one of our cars is not a hybrid.

Do you own a hybrid car? What has your experience been like?


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