Learning Exercise

Writing-to-Learn exercise

Ask students to describe the
physical and energetic transformations H2O undergoes as it proceeds through the
power generation process.
Course: Energy Balances; Thermodynamics

This is virtual tour of the Michigan State University power plant that uses four steam-powered turbines. The power... see more


Homework Assignment

Energy Balances
Physical and Energetic Transformations in Power Generation from Steam

Take virtual tour of the Michigan State University Power Plant on the web.

This website was originally developed by Dr. Carl Lira for one of his courses,
so there may be a few comments in the text that are specific to his course.

Using the information in the virtual tour, information in your text, and your
own knowledge and understanding of engineering, describe the power generation
process in terms of the physical and energetic changes undergone by the water at
each step. In other words, for each unit operation in the power generation

(1) Describe the changes in the thermodynamic state of the water
(temperature, pressure, phase, specific enthalpy) as it passes through that unit

(2) Describe how the energy is transferred to / from the water in each unit
operation, including identifying the source of / sink for the energy. If energy
is transferred to / from another flowing stream, explain whether the streams
are mixed together or whether the energy is transferred through a pipe wall or
something similar.

Your description of the power generation process should be an example of good
technical writing. It should give an overview of the process, and then discuss
the individual unit operations in a logical order. It should be clear, concise,
and use technical terms correctly.

Primary Traits for Grading

The student?s description correctly:

(1) Identifies all unit operations in the power generation cycle and lists
them in logical order.

(2) Identifies all changes in the thermodynamic state of water in each unit
operation, including a clear statement of whether the value of each state
variable increases, decreases, or remains constant.

(3) Identifies the source of / sink for energy transferred in each unit
operation and describes the mechanism of energy transfer.

(4) Provides a concise overview of the power generation process first. Uses
standard technical terms to name the unit operations and describe how they are
connected such that the description is understandable even without a diagram for

(5) Uses standard written English (complete sentences, correct grammar,
correct spelling). Avoids the use of colloquial language or anthropomorphism.

Technical Notes

May be used in-class or as homework, in teams or as individuals. Could also be used as a "first exposure" assignment, to get students to think about how to apply information they are to read in the texbook before they come to lecture.


Familiarity with the basic vocabulary of thermodynamics.


Specific enthalpy and its relationship to other state variables

Energy transformations

Power cycles, power generation

Steam tables

Learning Objectives

Identify unit operations that transfer energy to or from the H2O.
Equate changes in the temperature, pressure, or phase of H2O with changes in enthalpy.
Apply fundamentals of thermodynamics to the analysis of an engineering process.
Write a clear description of an engineering process using appropriate technical vocabulary.