2/25/14

Tonight's homework is to complete Assignment 42. Remember that there will be a dimensional analysis check-in tomorrow. Look over the examples that you've worked on so far and come prepared with questions.

Interesting video clip - "Germany's Coal Addiction" NY Times

Assignment 42 Coal Usage Calculation and Comprehension Questions

Answer all of the following questions to the best of your ability. Write in complete sentences where appropriate and show your work.

1. A large, coal-fired electric power plant produces 12 million kilowatt-hours of electricity each day. Assume that an input of 10,000 BTU’s of heat is required to produce an output of 1 kilowatt-hour of electricity.

a. Showing all steps in your calculations, determine the number of

i. BTU’s of heat needed to generate the electricity produced by the power plant each day,

ii. pounds of coal consumed by the power plant each day, assuming that one pound of coal yields 5,000 BTU’s of heat,

iii. pounds of sulfur released by the power plant each day, assuming that the coal contains one percent sulfur by weight.

b. The Environmental Protection Agency (EPA) standard for power plants such as this one is that no more than 1.2 pounds of sulfur be emitted per million BTU’s of heat generated. Using the results in part a. above, determine whether the power plant meets the EPA standard.

c. Describe two ways by which a fuel-burning electric power plant can reduce its sulfur emissions.

d. Other than mining and reclamation, describe two environmental impacts of using coal for energy.

e. Explain why per capita coal consumption in the United States is likely to increase.

2. Which of the following is a provision of the Surface Mining Control and Reclamation Act of 1977?

A. All deep shaft mines must be filled in when they are shut down.

B. Strip mining is not allowed on public lands.

C. Mining companies must replant vegetation on land that was strip-mined.

D. Mining companies must replant vegetation on land that was deep-mined.

E. Mining companies must clean up the water supply on land that was strip-mined.

3. Which form of coal has the highest sulfur content?

A. Peat                                                                         D. Anthracite

B. Lignite                                                                     E. Sub-bituminous coal

C. Bituminous coal

4. Which of the following has the largest proven coal reserves?

A. South America                                                        D. Indonesia

B. The United States                                                   E. Africa

C. Australia

5. Which of the following forms of coal burns the hottest?

A. Peat                                                                         D. Anthracite

B. Lignite                                                                     E. Sub-bituminous coal

C. Bituminous coal

6. How does today’s lesson relate to sustainability?