Right Lane Cruiser
04-29-2009, 07:54 AM
http://www.cleanmpg.com/photos/data/2/European_Union_Flag.jpg A cheaper way to increase fuel efficiency in cars. (http://www.economist.com/science/tm/displaystory.cfm?story_id=13568891)
http://www.cleanmpg.com/photos/data/501/Greening_of_Chicago_-_Argonne_Labs_-_TCH.jpgP. Rüegg - The Economist (http://www.economist.com) - April 29, 2009
What do they do with heat generated when compressing the air? --Ed.
BEING green can be expensive, as any driver of a Toyota Prius can tell you. The car is a hybrid, combining an electric motor that powers it at low speeds in the city with a petrol motor that is useful for accelerating and cruising at high speeds. It is the most efficient car sold in America, but it costs upwards of $22,000, a price that can wipe out the savings on fuel. One reason for the price is that the car contains expensive batteries. Another is that the transmission system had to be completely redesigned. But there may be a cheaper and altogether simpler way to make a hybrid that avoids this—using air power instead of electricity.
Using compressed air to power a car has one obvious disadvantage: compressed air has a low energy density, so the stored energy gets used up quickly. However, in urban driving, this may be more than compensated for using regenerative braking. One of the most important roles of the batteries in a hybrid is to store energy recovered when the car brakes. The idea with a pneumatic hybrid is to store this energy as compressed air. Such a vehicle would run on petrol but would use its reservoir of compressed air to boost the power when needed. This would not demand a serious redesign, because every car already has a makeshift air compressor in the form of the engine itself. Building a pneumatic-hybrid car would thus be relatively cheap.
When the driver of a pneumatic-hybrid car applied the brakes, the fuel supply to the engine would be shut off while the pistons that normally propel the vehicle would help to slow it, pumping pressurised air into a tank as they did so. According to Lino Guzzella of the Swiss Federal Institute of Technology in Zurich, who has built a prototype pneumatic-hybrid engine, this... http://www.economist.com/science/tm/displaystory.cfm?story_id=13568891
http://www.cleanmpg.com/photos/data/501/Greening_of_Chicago_-_Argonne_Labs_-_TCH.jpgP. Rüegg - The Economist (http://www.economist.com) - April 29, 2009
What do they do with heat generated when compressing the air? --Ed.
BEING green can be expensive, as any driver of a Toyota Prius can tell you. The car is a hybrid, combining an electric motor that powers it at low speeds in the city with a petrol motor that is useful for accelerating and cruising at high speeds. It is the most efficient car sold in America, but it costs upwards of $22,000, a price that can wipe out the savings on fuel. One reason for the price is that the car contains expensive batteries. Another is that the transmission system had to be completely redesigned. But there may be a cheaper and altogether simpler way to make a hybrid that avoids this—using air power instead of electricity.
Using compressed air to power a car has one obvious disadvantage: compressed air has a low energy density, so the stored energy gets used up quickly. However, in urban driving, this may be more than compensated for using regenerative braking. One of the most important roles of the batteries in a hybrid is to store energy recovered when the car brakes. The idea with a pneumatic hybrid is to store this energy as compressed air. Such a vehicle would run on petrol but would use its reservoir of compressed air to boost the power when needed. This would not demand a serious redesign, because every car already has a makeshift air compressor in the form of the engine itself. Building a pneumatic-hybrid car would thus be relatively cheap.
When the driver of a pneumatic-hybrid car applied the brakes, the fuel supply to the engine would be shut off while the pistons that normally propel the vehicle would help to slow it, pumping pressurised air into a tank as they did so. According to Lino Guzzella of the Swiss Federal Institute of Technology in Zurich, who has built a prototype pneumatic-hybrid engine, this... http://www.economist.com/science/tm/displaystory.cfm?story_id=13568891