Conversion Efficiencies of Heat Engines and Fuel Cells

The Carnot cycle efficiency derived in Section 3.1 was based on the First Law, but having two definitions of conversion efficiencies gives a more accurate assessment of a power-producing device. The first definition is that of thermal efficiency, which is based on the First Law, comparing the net work output with the heat input, usually the heating value of the fuel. Using this as standard of reference, devices with different energy conversion processes can be compared against each other.

The second definition is based on the Second Law, which compares the actual performance of a device to the maximum possible work that it could produce, which, for example, is the Carnot cycle efficiency for heat engines. This shows where there is room for improvement. By using the concept of exergy, the Second Law is a measure of efficiency relative to the maximum work potential of a system.

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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