What is the True Cost of Burning Coal?

Justin C. Lytle, Pacific Lutheran University

Summary

I designed an open-ended learning activity for my general chemistry students as a framework for them to explore the costs, ethics and alternatives to coal-fired electricity. In this activity, students will research energy-related issues that are related to the "big idea" that $0.06/kWh electricity from burning coal may be deceptively and dangerously cheap. The assignment culminates in an essay that responds to key points about the short-term and long-term economics of coal-fired electricity. Students are also asked to comment on the economics of carbon capture and sequestration technology, and to define the differences between a carbon tax and cap-and-trade emissions policies. Students are asked to propose how they might make compromises to balance our American lifestyles with the reality that coal provides a massive amount of energy that is not going to be replaced overnight by alternative energy technologies.

Learning Goals

The essay component of the learning activity asks students to answer two big questions: (1) Does coal-fired electricity really cost $0.06/kWh? and (2) Are there reasonable alternatives to burning coal for electricity?

In regards to the second big question, students are asked to consider whether there are reasonable and more ethical energy alternatives to coal. I have been intentionally ambiguous with my students about my own views on these issues, and I have framed the question in a open-ended fashion so that they are faced with the reality that there are not necessarily black-and-white solutions, but instead a series of gray compromises that we must fully understand. I hope to inspire students to relate to these real-world issues on a more personal level than they would otherwise do if they were simply recording their data and observations in a formal laboratory writing assignment. I also aim to quench the all-too-simple solution of revolutionizing our energy infrastructure overnight with solar and wind energies. I believe that the magnitude of coal-fired electrical energy will convince them that replacing coal is not without major challenges.

The purpose of this exercise is to pose this dilemma to general chemistry students in order that they might think about the real costs of coal-fired electricity, the ethical dilemmas it poses, and to have students explore any reasonable alternatives to supplying electrical energy.

Context for Use

I developed a sequence of teaching and learning activities around the topic of coal-fired electricity. This sequence on coal fits logically between the chapters on electrochemistry and nuclear chemistry in my general chemistry class, because I think that students will see strong connections between storing electrical energy (in batteries and fuel cells) and generating electricity from nuclear fission. This material falls approximately two-thirds through the course, and will commence with a 20-minute lecture on the benefits and disadvantages of coal-fired electricity, as framed in terms of economics, environmental issues, and human health. Students have one week to review articles about these issues and complete an essay giving their perspective on the real costs of burning coal.

Description and Teaching Materials

Introduction and Overview

Coal-fired electricity is the most inexpensive source of power on the planet. American households pay as little as $0.06 per kilowatt-hour (kWh) for electricity that is generated by burning coal, and this abundant source of cheap power is partly responsible for some of the economic success that the United States has enjoyed. A staggering 49% of U.S. energy needs are met by burning coal, corresponding to an unbelievable 168 terawatt-hours that support our enviable standards of living. As many people realize, though, there are more costs to burning coal than meet the eye. Six cents per kWh (the amount of electricity needed to power sixteen 60-Watt light bulbs for one hour) does not take into account that coal exacts tolls on the environment and human health. The purpose of this exercise is to pose this dilemma to general chemistry students in order that they might think about the real costs of coal-fired electricity, the ethical dilemmas it poses, and to have students explore any reasonable alternatives to supplying electrical energy. The topic of coal is very appropriate for my general chemistry class, because it reiterates several chemical phenomena: acid rain, photochemical smog pollution, bioaccumulation of mercury, and greenhouse gases.


Initially, I will deliver a twenty-minute presentation titled "The True Co$t of Coal" to my general chemistry students. The lecture will serve as a segue between my class' chapters on electrochemistry and nuclear chemistry, which seems a logical fit for a discussion about electricity. The beginning of the lecture is intended to overwhelm the students with the enormous amounts of coal-fired electricity that are currently in-play on the U.S. electrical grid. The presentation will then transition into a discussion of the environmental and ethical ramifications of burning coal. Specifically, I distinguish the short-term costs of coal versus the long-term toll that it exacts on human health and the health of the environment. I will finally define the learning activity as an opportunity to review the existing literature about these and related issues, and drafting a short essay that evaluates the true economic, ethical, and environmental costs of coal-fired electricity (see the attached assignment). I complete the circle by tabulating and sharing the general trends from these essays back to the students, so that they might learn what others think about these critical issues.

The essay component of the learning activity asks students to answer two "big questions": (1) Does coal-fired electricity really cost $0.06/kWh? and (2) Are there reasonable alternatives to burning coal for electricity? Students review any recent articles and books about energy technologies and coal in order to formulate their thoughts. In regards to the first question, students are asked to define the short-term and long-term costs of coal-fired electricity, and compare these to the costs of electricity that is generated from other fossil fuels, nuclear, and renewable energy technologies. Students are also asked to comment on the economics of carbon capture and sequestration technology, and to define the differences between a carbon tax and cap-and-trade emissions policies. In regards to the second "big question," students are asked to consider whether there are reasonable and more ethical energy alternatives to coal. I have been intentionally ambiguous with my students about my own views on these issues, and I have framed the question in a open-ended fashion so that they are faced with the reality that there are not necessarily black-and-white solutions, but instead a series of gray compromises that we must fully understand. I hope to inspire students to relate to these real-world issues on a more personal level than they would otherwise do if they were simply recording their data and observations in a formal laboratory writing assignment. I also aim to quench the all-too-simple solution of revolutionizing our energy infrastructure overnight with solar and wind energies. I believe that the magnitude of coal-fired electrical energy will convince them that replacing coal is not without major challenges.


The True Cost of Coal (Microsoft Word 115kB Oct31 11)


Teaching Notes and Tips

In the early stages of the assignment, I notice that some students are unsure of how scientifically technical to be in their essays, because the assignment steps out of the scientific mindset that they are used to and enters outside disciplines like economics and philosophy. In the future, I will clarify my interest in a non-technical writing approach, but I will ask students to specify the chemistry of coal combustion and of pollutants found in coal. Likewise, students are uncomfortable with having such a wide-open topic, and I would refine the topic to simply ask whether coal-fired electricity is really $0.06/kWh. Many students easily exceeded the three-page minimum that I imposed, and have spent too much time comparing the details of all available energy resources. On one hand, I am pleased with this outcome because students are being exposed to a wide range of relevant information. On the other hand, it is enough for me to awaken their curiosity about this subject and not to set the definitive word on the subject of coal-fired electricity. In hindsight, I would clarify that I expect students to identify issues, but not necessarily to discuss each one in the interests of helping students to manage their time effectively.


Finally, I found it very time-consuming to keep a running tally of all the unique viewpoints that students have on this subject. Even though my intentions were to report a summary of my class' essays back to the students, this amounted to a Sisyphean task. In the future, I will develop an assessment rubric for students to succinctly state their stance on the "big idea" about the true cost of coal, and to identify possible solutions. This reorganization should enable me to rapidly tally the opinions of my class.

In the future, I will create a question-and-answer form for students to succinctly state their views, from which I will collate their responses and share this information with my class so that they can see how their peers think about these critical issues.

Assessment

It would be all-too-easy for students to disingenuously regurgitate green mantras about decisively cutting our addiction to coal, but responses like those would undermine the important learning opportunities that exist in this assignment. For that reason, I will be explicitly clear that essay responses that rely on simple answers- such as converting overnight our energy infrastructure to renewables- will receive minimal grades, whereas I will reward good ideas and critical thinking that deal with the pros, cons, and compromises that are inherent to coal-fired electricity. I am specifically looking for students to identify short-term and long-term costs of coal, but am not requiring them to estimate the actual monetary value of any nebulous costs. I have created a list of similar points that I want students to address, including the costs of other energy-conversion technologies and the ethical dilemmas raised by burning coal.

References and Resources

I have provided numerous Internet links to articles about coal, electrical energy, alternatives to coal, and environmental aspects to the burning of coal for electricity (see the attached assignment). Students are welcome to use any resource that they find relevant, as long as it is properly cited and defends their position(s). I urge students to see this complex issue from multiple angles, which is why I have included viewpoints from both ends of the political spectrum.

Evergreen State College