Stirling Heat Engine: This engine, invented by Robert Stirling, is a much different and more efficient engine than what is in any gas or diesel powered car on the market today. The reason for this potential of such a greater efficiency in the Stirling Engine is that all the gasses used to power the engine never actually leave the engine; therefore, there is no exhaust and the engine runs very quietly. This process is called the “Stirling Cycle,” and uses an external heat form from gasoline to solar power. This engine operates on a mechanical cycle created by the external heat source being converted into the mechanical energy. Because the engine operates on a completely closed cycle, it is able to regenerate the heat energy that it needs to power the mechanical spinning of the engine. Some of the main applications of the Stirling Engine are for marine vehicles and solar power generation because each use the heat energy to create either mechanical power to drive a marine vehicle, or the generation of solar powered electricity.

Peltier Device: The Peltier Device is simply a thermodynamic cooler that operated based on the Peltier effect. This effect is a theory that states that a cooling effect, as well as a heating effect, occurs when an electrical current passes through two dissimilar conductors. The voltage applied to the ends of these conductors is what creates the temperature change because the heat is forced to move from one end to the other.Usually these coolers are comprised of  range of different elements that make up the two dissimilar conductors, typically connected through two ceramic plates that give off the temperature change.

http://auto.howstuffworks.com/stirling-engine.htm

https://en.wikipedia.org/wiki/Stirling_engine

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