Question

The maximum amount of low grade energy, which is convertible into work is known as

• A. Anergy
• B. Exergy
• C. Entropy
• D. Energy loss

Hint:

Remember the simple word formula: $\text{Energy} = \text{Exergy} + \text{Anergy}$. - $\text{Exergy} = \text{Available energy (can be converted into work)}$. - $\text{Anergy} = \text{Unavailable energy (cannot be converted into work)}$.

Answer 1

The Correct Option is B

The question asks about the term used to describe the maximum amount of low-grade energy that can be converted into work. Let's analyze the given options to find the correct answer:

1. Anergy: This term is generally used in thermodynamics to denote energy that cannot be converted into work. This concept is more closely related to unavailable energy, not the convertible portion.
2. Exergy: Exergy is defined as the maximum useful work possible during a process that brings a system into equilibrium with a heat reservoir. It represents the portion of energy that can do work. This matches the description given in the question.
3. Entropy: Entropy is a measure of disorder or randomness in a system, and it does not directly denote convertible energy.
4. Energy loss: This term refers to any energy that is not used effectively and is lost to the surroundings, typically as heat, and it does not pertain to maximum convertible work.

Upon reviewing the options, Exergy is the correct choice because it represents the maximum usable energy that can be converted into work under given conditions.

Exergy, also known as availability or available energy, is fundamental in evaluating energy systems for efficiency and potential improvements. Understanding the concept of exergy is crucial in fields like mechanical engineering, especially for optimizing thermal and power systems.