652 Pressure

The direct effect of the operating pressure of a fuel cell is to change the concentration of reactants at the electrode surfaces. Thus, according to the Nernst equation, as operating pressure increases, partial pressures of reactants increase and the reversible cell potential increases. In addition, as operating pressure increases, gas solubility and mass transfer rates increase, reducing some overpotential associated with these processes. Electrolyte loss by vaporization is typically reduced and overall system efficiencies are increased with increasing operating pressure. However, parasitic losses, in particular those associated with the compression of the air (and fuel) stream, increase with increasing operating pressure. In addition, increased materials requirements (larger pipes, containment vessels) and increased controls hardware must be taken into consideration in the system design to ensure increased performance with increased operating pressure.

Solar Stirling Engine Basics Explained

Solar Stirling Engine Basics Explained

The solar Stirling engine is progressively becoming a viable alternative to solar panels for its higher efficiency. Stirling engines might be the best way to harvest the power provided by the sun. This is an easy-to-understand explanation of how Stirling engines work, the different types, and why they are more efficient than steam engines.

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