Almost all cars still waste more than 60% of all energy they consume, mostly due to the lost of heat lost in the exhaust system or radiator.

Terry Tritt, physicist at Clemson University, states that if one saves only a small amount of that energy (7 to 8%), this might save up to 1.5 billion gallons of diesel a year in heavy trucks alone. One way might be through hermoelectric generators that convert heat into electricity.

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Last week Terry Tritt said on the Department of Energy (DoE) conference in Dallas:
"Thermoelectric generators are currently used in NASA's deep-space probes to convert the heat of radioactive elements to electrical energy." Moreover: "One of the more promising 'down-to-earth' applications lies in waste-heat recovery in cars."

This idea is not new: Thermoelectric devices have helped NASA power spacecraft for some 30 years. When there is a temperature difference across those devices the material devolps voltage...

...if you are interested in more information about this check the Clemson Uni website...

60% waste of energy? Sound familiar to me: Siemens Gigaset phones promise to save 60% energy. Take a look: Siemens Gigaset ECO DECT phones