Exergy and Energy : Are you familiar

Whenever a geothermal location is chosen for developing a nuclear power plant the first thing that engineering look for it is the available energy or exergy that can be extracred from it.  If you are from engineering background or a real thermodynamics lover you might be knowing what energy is if not this small article will help you to know some basics about energy and energy.
Energy is also known as the ability to do work or perform task, energy follows the law of conservation and it cannot be created nor be destroyed but can only be transformed from one form to another. Like you can transform work into heat and heat into electricity and vice versa but Cannot produce any energy on own however the quality of energy differs time to time somewhere it may be a high grade energy which is the energy which is capable of producing more power and low grade energy which is of the same magnitude as the high grade energy but cannot have much power producing capacity. Energy is present in every atom of every material but it depends on the vibrations and the state on atoms to which amount it produces energy.

Exergy is a part of energy but it differs from energy in the fact that it is only the useful energy or available energy capable of producing work, as energy can be useful energy(exergy)or useless energy(anergy). Exergy can be understood well by taking example of a heat engine cycle, we all know a that work can only be produced In a cycle if heat is exchange to a two temperature reservoir if heat is taken from high temperature reservoir and some heat is rejected to low temperature reservoir which is also energy but useless energy(anergy)and some energy which produces work to derive the shaft or turbine is the Useful Energy or Exergy. Our environment is full of energy but at any certain time it's Exergy is zero because no work output can be obtained from it.
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