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Prius Hybrid


Prius Hybrid - Disadvantages of Hybrid Cars

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The name Prius is virtually synonymous with the word Hybrid. When the Prius was first introduced, the car was costing Toyota $40,000 to build and they were selling it for $20,000 at the dealer. Being first to market with a hybrid was just that important to them. And it is why I think the Prius is the icon of hybrids.

The Prius does a superb job of getting high gas mileage. Owners are reporting gas mileage greater than 62 mpg on fueleconomy.gov. And they're also reporting lower numbers in the 32 mpg range. The average still works out to be 46 mpg.


How Do Hybrid Cars Work?

The hybrid automobile system uses a conventional gas engine as the primary source of power. The gas engine is mechanically linked to the wheels. An electric motor is also mechanically connected to the wheels. The gas engine and electric motor directly move the wheels of the car; however, not always at the same time.

The hybrid batteries get charged when the brakes are applied, or when the engine computer tells the gas engine to charge the battery. The recaptured energy from gasoline means the gas engine doesn't need to run all the time. But it does mean that all the energy in the battery comes from converting gasoline into electricity.

Because all the mechanical energy in a hybrid comes from gasoline, it is calculated like a gas engine in the efficient-mileage rating chart. And because the hybrid system does recapture lost energy, it does really improve efficiency.

However, like many engineers that I've talked to, I have had an intuition that hybrids aren't as efficient as everyone thinks they are. In fact, the Prius is about 40% more efficient than most cars on the road. That's really quite impressive. However, the 2008 Porsche 911 is also 40% more efficient than most cars on the road too. And the Porsche 911 has no hybrid system. Then again, the Porsche 911 averages about 19 mpg.


Costs: Prius VS. non-hybrid Civic

Efficiency benefits or shortcomings aside, the great gas mileage is ideal for the ultimate economical car. The costs and benefits of owning a Prius have been weighed many ways in various publications. The Rocky Mountain Institute did a thorough cost analysis between a 2008 Honda Civic and 2008 Toyota Prius. The comparison required that the car be owned for three years, driven 12,500 miles per year on $4 per gallon gasoline, $575 in maintenance, and a 24 month loan.

Total payments before the resale:
Prius: 23,384(car)+1,740.54(interest)+575(maint.)+3,260.87(gas)=$28,960.41

Civic: 17,751(car)+1,321.26(interest)+575(maint.)+5,172.41(gas)=$24,819.67

The Prius is said to sell for $18,135 after 3 years of ownership

The Civic is said to sell for $12,290 after 3 years of ownership

If the Prius can retain its value after three years and it is sold after three years, it will come ahead of the Civic by $1704.26. Of course, if the $9,000 battery in the Prius fails out of warranty, then that cost will easily eat up the marginal gain several time over.

A difference of $1700 over three years isn't going to sell a car. We're basically splitting hairs here. And the end result is a loss of $10,000 to $13,000 dollars over three years. And then you'll have to buy a new car since you sold your daily driver.


But I thought a hybrid would save more gas money!

Anyone can see that 46mpg could save more gas than a 29mpg car. But how much more? A quick glance may show a 59% savings by choosing the Prius (46-29)/29=59%. However its easy to be deceived. The savings is really 35%! (34-22)/34 Does that still sound like a lot of savings?

The Prius averages 46 mpg and consumes about 22 gallons per 1,000 miles.

12,500 miles x 3 years x 22 gallons per 1000 miles = 825 gallons

825 gallons x $4 gallon gas = $3,300

The Civic averages 29 mpg and consumes about 34 gallons per 1,000 miles.

12,500 miles x 3 years x 34 gallons per 1000 miles = 1275 gallons

1,275 gallons x $4 gallon gas = $5,100

$5,100 - $3,300 = $1800 in gas money savings from the hybrid after three years on $4/gallon gasoline.

The Prius costs $5,633 more than the Civic. After three years, the Prius has yet to pay for itself even on $4/gallon gasoline. It is still owes $3,833 to the Civic.


What's The Point of all this?

The point is that paying more than $1000 to get more than 30 mpg won't result in an economical net gain. Hybrids do not pay for themselves. And the fuel/carbon savings isn't that substantial over a 30mpg car.


The Disadvantages of Hybrid Cars Are:

There is not usually a return on the investment.

The fuel and emissions saved over a 30mpg car is not that significant.

Hybrid automobiles are completely dependent on gasoline.

Replacing hybrid batteries may cost about $10,000.

Large lead acid, and metal hydride batteries are not earth friendly.


Read about:

What is an economical car?

Tesla Roadster

The MPG Illusion

The MPH Illusion

Acceleration Test

Hydrogen Fuel Cells and the Honda FCX Clarity

Find out how to improve gas mileage in your car


Here's a fun video by Top Gear of the BBC. The Prius gets 17.2 mpg on the track!

Refresh the page if the video isn't working properly.


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