Everyone knows that the latest generation of hybrid automobiles delivers much better fuel mileage than the gas guzzlers of yesteryear. The Toyota Prius gets 51 mpg on the highway, 60 mpg in the city, the Honda Civic Hybrid gets 51 mpg on the highway, 49 mpg in the city, and the other hybrids on the market that combine electric motors with small gasoline engines all get similar numbers. The equation seems simple enough; the electric motors extend the range of hybrid vehicles to the point that they get great mpg even when running on their small gas power plants.
Hybrid vehicles get better mileage than gas-powered vehicles because the electric motor greatly reduces the amount of work the gasoline engine has to perform. The electric motors are powered by battery packs on the vehicle, and are recharged during braking, eliminating the need for recharging them from an external power supply. The result is fuel economy of around 50 miles to the gallon of gas.
Today however, there are several new electric-powered vehicles entering the market that are making triple-digit mileage claims that are a bit more difficult to grasp. Chevrolet claims its new Volt electric hybrid sedan will get an astounding 230 miles to the gallon of gas. Nissan claims its 2011 LEAF EV will actually achieve an unheard-of 367 mpg using the same EPA guideline utilized to calculate the Volt’s mpg numbers. Those numbers are far beyond anything people are used to and have caused some to doubt the math used to achieve such lofty fuel economy estimates. Indeed, it can be puzzling to consider calculating the fuel mileage of a vehicle that carries no fuel at all, like the Nissan Leaf. The Volt has a gas tank, but the Leaf does not, and it leads one to wonder how they calculated the “gas mileage.”
The Chevrolet Volt runs on electricity that comes from a battery and is powered by a gasoline engine too, but it will only get around 50 mpg when it is operating on gasoline alone. The 50 mpg figure does not take into account that the car has already gone 40 miles on electric power alone without using any gas at all. It is a confusing situation, but becomes a bit clearer when the total mileage driven is taken into consideration.
If a Volt was driven 50 miles, no gas would be used at all during the first 40 miles and during the last 10 miles, 0.2 gallons would be consumed. At that point, the fuel mileage would be a terrific 250 miles per gallon. However, if the Volt continued to drive to the 80 mile mark, the fuel economy would drop to around 100 mpg. The farther you drive a Volt, the less advantage the electric motor provides and if the car is driven for a full 300 miles the fuel economy drops down to just 62 mpg.
If it sounds confusing, it probably is, and we’re betting that the car manufacturers will be using the confusion to their advantage when they begin advertising the fuel economy of their hybrid or electric, extended-range vehicles. In a market that is rapidly becoming populated with a number of different types of hybrid/electric/combination power plants it is going to become increasingly difficult to compare apples to apples or even apples to oranges because there are so many different flavors available.
Prospective buyers will have to consider their real world driving habits to make any sort of fair comparisons between vehicles and the distances they drive will become much more important components of their purchasing decisions. The prices of the latest hybrid/electric cars are definitely higher than existing hybrids and even with low electric recharging costs and less fuel consumed, it could take many years before the fuel savings justifies the price tag on a small car that costs well over $30,000.
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