Exergy as a Useful Variable for Quickly Assessing the Theoretical Maximum Power of Salinity Gradient Energy Systems

Entropy

关键词: exergy;    salinity gradient energy systems;    electric power;   

DOI  :  10.3390/e11040798

来源: mdpi

【 摘 要 】

It is known that mechanical work, and in turn electricity, can be produced from a difference in the chemical potential that may result from a salinity gradient. Such a gradient may be found, for instance, in an estuary where a stream of soft water is flooding into a sink of salty water which we may find in an ocean, gulf or salt lake. Various technological approaches are proposed for the production of energy from a salinity gradient between a stream of soft water and a source of salty water. Before considering the implementation of a typical technology, it is of utmost importance to be able to compare various technological approaches, on the same basis, using the appropriate variables and mathematical formulations. In this context, exergy balance can become a very useful tool for an easy and quick evaluation of the maximum thermodynamic work that can be produced from energy systems. In this short paper, we briefly introduce the use of exergy for enabling us to easily and quickly assess the theoretical maximum power or ideal reversible work we may expect from typical salinity gradient energy systems.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.