Speaker 1: Welcome to Brainstuff from house stuff Works dot com where
Speaker 1: smart happens. Hi Am Marshall Brain with today's question, is
Speaker 1: it possible to create one hundred mile per gallon cars
Speaker 1: that can run on real roads? Recently a car drove
Speaker 1: from the Canadian border in Washington State all the way
Speaker 1: down to the Mexican border in California on I five.
Speaker 1: That's nearly fifteen hundred miles. What was amazing about the
Speaker 1: trip was the fact that the car burned on the
Speaker 1: twelve point four gallons of fuel. The car got an
Speaker 1: average of a hundred and nineteen miles per gallon. This
Speaker 1: was not a weird experimental car made out of tissue
Speaker 1: paper with the driver lying in a prone position looking
Speaker 1: out through a periscope. This was a real two passenger
Speaker 1: car that looked pretty normal. The car, called the Avion,
Speaker 1: proved once and for all that it's possible to create
Speaker 1: one hundred mile per gallon cars that can drive on
Speaker 1: real roads under real conditions. What's even more amazing is
Speaker 1: the fact that the car was not created by a
Speaker 1: university research team or NASA scientists. The car was originally
Speaker 1: created in the nineteen eighties by Craig Henderson, and Bill
Speaker 1: Green and has been tweaked ever since. It brings up
Speaker 1: a good question, how can our cars get better mileage
Speaker 1: per gallon of fuel. Let's look at the different techniques
Speaker 1: that the Avion uses. The most important feature of the
Speaker 1: Avion is its aerodynamics. Airflow has a huge effect on
Speaker 1: the car's fuel efficiency, especially at highway speeds. A typical
Speaker 1: car might need ten to twenty horsepower to maintain highway speed.
Speaker 1: The Avion needs far less, down to three to four
Speaker 1: horsepower to achieve the same speeds. The reason the Avion
Speaker 1: is so slippery is that it takes into account the
Speaker 1: major sources of dragon conventional cars and eliminates them. A
Speaker 1: big part of it is the shape of the rear
Speaker 1: of the car. Think about a raindrop. It has a
Speaker 1: bulbous nose and a long sloping tail. The longer tail
Speaker 1: is important, so the avions rear end looks a lot
Speaker 1: like a rain drops. The Avian is also a low car.
Speaker 1: Many of today's cars, especially SUVs and minivans, are taller
Speaker 1: than a person. This means that the car has to
Speaker 1: move a lot of air out of the way as
Speaker 1: it's going down the road. The Avion is built like
Speaker 1: a low sports car, so there's less air to move
Speaker 1: in a conventional car. There is lots of extra sources
Speaker 1: of drag. The underside of a conventional car is all bumpy,
Speaker 1: with many extraneous pieces catching the wind. It is possible
Speaker 1: to make the underside smooth like a race car and
Speaker 1: eliminate a lot of air resistance there. There is a
Speaker 1: big vertical grill up front in most cars, acting like
Speaker 1: a wall to the wind. Spoke wheels chop at the air.
Speaker 1: The Avion addresses all of these problems and corrects them.
Speaker 1: Another kind of drag comes from the rolling resistance of
Speaker 1: the tires. Big fat tires with low air pressure create
Speaker 1: a lot of rolling resistance. The Avion uses low resistance
Speaker 1: tires on its trips. Many hybrids are using these tires
Speaker 1: as well to improve their performance. Another thing helping the
Speaker 1: Avion is its weight. It's made of aluminum and other
Speaker 1: lightweight materials, so that it weighs half as much as
Speaker 1: a normal car. The weight helps whenever accelerating or going
Speaker 1: up a hill. Think about the amount of energy needed
Speaker 1: to get a ping pong ball going five miles an hour.
Speaker 1: Now compare that to the energy needed to get a
Speaker 1: bowling ball going the same speed. The ping pong ball
Speaker 1: requires the slightest touch. The bowling ball requires a big push.
Speaker 1: In a car, extra weight means extra fuel being burned
Speaker 1: every time you climb a hill. And then there's the engine.
Speaker 1: This car uses a tiny diesel engine that's smaller than
Speaker 1: the engine found on many motor cycles. It doesn't need
Speaker 1: a giant engine because the car is so light and
Speaker 1: so slippery. The fact that it's a diesel also helps.
Speaker 1: Diesel fuel contains more energy per gallon than gasoline does,
Speaker 1: so that helps right from the start, and a diesel
Speaker 1: engine uses a higher compression ratio, making it even more efficient.
Speaker 1: By putting all these things together, great aerodynamics, great tires,
Speaker 1: low weight, in the most efficient engine possible, it's possible
Speaker 1: to create a car with great mileage with what these
Speaker 1: techniques will trickle in the mainstream cars now that they've
Speaker 1: been proven to work. Be sure to check out our
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Speaker 1: Work staff as we explore the most promising and perplexing
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