An Introduction to Alternative Energies, with Emphasis on the Hydrogen Fuel Cell

An Introduction to Alternative Energies, With Emphasis on the Hydrogen Fuel Cell

Eric Sladek Pre-Service Teacher WSU Tacoma, WA

Jim Stewart Garfield – Palouse High School Palouse, WA

Washington State University Mentors Dr. Su Ha Chemical and Bioengineering WSU

Sean Lin Graduate Assistant

The project herein was supported by the National Science Foundation Grant # EEC- 0808716: Dr. Richard L. Zollars, Principal Investigator and Dr. Donald C. Orlich, co-PI. The module was developed by the authors and does not necessarily represent an official endorsement by the National Science Foundation. TABLE OF CONTENTS:

Goals ………..………………………………………..3 Objectives…………………………………………….3 Estimated time………………………………………..3 Target audience………………………………………3 Tools………………………………………………….4 Pre-requisite knowledge……………………………...4 Rationale for project………………………………….4 Project description……………………………………5 Teacher led Module…………………………………..7 Appendix Projects………………………………………...... 10 Uses and advantages of Fuel Cells…………………..12 Worksheet 1: Alternative Energy Conversions……...13 Worksheet 2: Fuel Cells………………………..……15 Worksheet 3: Need for Engineers…………………...17 Formula Page………………………………………..19 Answer Guide……………………………………….21 Diagrams……………………………………………23

2 Goals

1. Introduce students to a various forms of energies. 2. Motivate students to understand the world’s need to move towards a more “balanced” energy system that is less dependent on those fuels that are greenhouse emission rich. 3. Introduce students to different aspects of engineering, with the hope of motivating them to consider that path. 4. Highlight the hydrogen economy and show some of its applications, advantages and disadvantages.

Objectives: 1. Student will be able to describe the difference between a battery and a fuel cell. 2. Student can describe the basic structure of a fuel cell. 3. Student can list advantages and disadvantages of various forms of fuel cells. 4. Student can list advantages and disadvantages of various forms of energy (wind, solar, nuclear, etc.) 5. Students will use mathematics to justify their opinions of the direction of energy research. Target audience:

Mathematics: 10 –12 Science: 10 – 12 Social studies 12 (Current world issues) Ag-Science 9 – 12

Estimated time:

Approximately 135 - 210 minutes (2 – 4 class periods) 90 - 120 minutes to fully view presentation 45 - 90 minutes for assessment

3 Tools:

Computers with sound capability and internet access. Graphing calculator or Excel.

Pre-requisite knowledge:

Understanding of ratios and proportions (dimensional analysis). Knowledge of exponential functions and logarithms. (2 questions on assessment) Ability to use a graphing calculator or Excel to create a Cartesian graph. Ability to analyze a Cartesian graph. Ability to read various statistical plots (bar graph; pie chart, line graph). Basic algebraic manipulation. Ability to navigate a menu driven computer program.

Rationale for Project :

It is our belief that there is no one source of energy that will allow us to cast off those energy sources, such as gas and coal, that are damaging our environment through the emissions of greenhouse gasses. We must find a variety of sources for our energy, and develop more and better methods to turn “waste products” back into energy. This goal can only be accomplished through an enlightened populace and with the help of what needs to be a growing engineering population. This project is meant to inform and hopefully excite young people to explore alternative energies and moreover to use their skills to become engineers to help solve this problem. The focus energy for the project is hydrogen, and in particular the hydrogen fuel cell. Hydrogen is the most abundant fuel source on earth. The “waste products” developed from the hydrogen fuel cell are water and heat. We cannot be too disappointed to have a little extra water (in fact the astronauts have used this waste product to drink on space flights). The heat lost can often be harnessed to be recycled into more energy. The hydrogen fuel cell is being used for many applications today, ranging from space travel to institutional power plants. It has been used to power small

4 communities that are “off the grid”. Fuel cells are available that will power your laptop for up to 12 hours of continuous use. Because a fuel cell relies on fuel and a reaction to create electricity (rather than the stored energy of a conventional battery) as long as you have fuel you can have electricity. Even a rechargeable battery such as a lithium ion needs electricity to restore its potential. Fuel cell automobiles have been developed to travel up to 300 miles before refueling (Bunkley, New York Times). Communities have installed experimental fuel cell buses. Fuel cell power plants and automobiles are much quieter than those now presently employed. Unfortunately, hydrogen is not without problems. Because it does not occur on its own naturally, it must be separated from other fuels. This process, depending on the fuel chosen, can lead to CO2 emissions The advantage here is that the CO2 is more easily contained, and possibly used or sequestered. Because of hydrogen’s structure storage can be a problem as well. Many containers and hoses that we use for gasoline now will not be sufficient for hydrogen. Fuel cell technology is reasonably expensive. Automobiles need a wider traveling range. Much more research needs to be put into this, and other fuel sources if we are to overcome the energy and environmental problems we face. We need more engineers working to solve this problem.

Project Description:

Our project is a power point presentation. Through these slides and short videos the students will be introduced to a wide range of energy sources. The slides are done in a way to hopefully capture the students’ attention while offering a brief background on some of our energy alternatives. A power point presentation was chosen for its simplicity to the user. The module is left open ended and we believe that it could be adapted for a variety of different age groups and subjects. We both often wished through the course of the project that we were chemistry teachers because the process of getting hydrogen, the catalyst process to liberate the electrons, through the eventual powering of a device and development of waste products seem to really lend themselves to this subject. However, we feel that the module could be beneficial to any science or math class.

5 Parts of the module could be used in classes as diverse as social studies, economics as well as shop or agricultural science classes. The power point is menu driven. The user can pick from a variety of options: alternative fuels; fuel cells; applications of fuel cell; history of the fuel cell. The students may start at the beginning and work their way through, or pick any element they choose. Depending on the outcomes expected the teacher should ask the students to focus on various topics, but be willing to explore and keep an open mind. The students can go self paced through the presentation, or the class may be guided by the teacher. The module offers a series of questions spread throughout, asking the students to reflect on the ideas presented in the previous slides. Again, the teacher can lead discussions; students can do them as a writing assignment; or they can use them as a jump off to a research project. We will describe the module as a teacher directed activity.

6 Teacher led Module The teacher will have the power point presentation loaded on his/her computer with projection capabilities. It would be advantageous, though not necessary to have access to the internet as well, as the program does have links to videos that the teacher may want to show. Begin at the main menu. Define Fuel Cell: a device used to create electricity that uses as fuel and a reaction rather than stored energy. What are the parts of a fuel cell? From the menu go to “How hydrogen fuel cells work” (the red slides). Show the first four slides and give the students a handout (see appendix) of the two fuel cell diagrams shown on the third and fourth slides. Ask the students to find all of the common elements for these diagrams. They should find: Anode Cathode Catalyst Membrane (PEM – on one slide it is called a Proton Exchange Membrane, and the other is a Polymer Electrolyte Membrane. They are the same thing.) Hydrogen Oxygen Water Load (something to power) Electrons.

HOW A HYDROGEN FUEL CELL WORKS: The fuel for all fuel cells is hydrogen. Hydrogen comes in pairs. It is made up of one proton and one electron. The hydrogen is introduced into the anode (negative side), where it meets and reacts with a catalyst (platinum) splitting the proton and electron apart. The membrane allows the proton to go through to the cathode side while the electron is routed around the membrane and out to power whatever device needs electricity. The electron continues through the circuit back to the cathode side where it meets up with the proton to reform hydrogen. Oxygen is being introduced on the cathode side, and with the help of another catalyst, combines with the hydrogen to

form water (H20). Thus, the waste product for a fuel cell is water (and like all batteries, heat).

7 To emphasize this process ask for 9 volunteers from the crowd. Mark areas on the floor as anode and cathode with the membrane between them. Your will need the volunteers to play the parts of: proton (2); electron (2); catalyst (2); membrane (1); oxygen (1) and load (1). Have the protons and electrons hold hand (proton, electron, proton, electron) to simulate the hydrogen coming to the cell. When they get to the anode side of the fuel cell have the catalyst break their hands (ionization). When they get to the membrane, he/she allows the protons through and directs the electrons over to the load. The electrons go past the load (having them doing something like a high five to simulate power might be helpful) and then over to the cathode. The protons, electrons and oxygen will meet, where the catalyst puts them back together (proton, electron, oxygen, proton, electron) to form water and they leave the cathode. If you have time and more kids you may try to introduce some element of competition to try to “create more electricity”. Have the students reconvene and go back to the presentation to complete the last four of the red slides. These slides show four other types of fuel cells (Phosphoric acid, Solid Oxide, Alkaline and Formic acid), and discuss some uses for them. There will be some minor differences between these and the PEM’s that you saw before, but the same basic parts (anode, cathode, catalysts, some type of membrane, hydrogen, oxygen and a waste product of water). If you have access to a fuel cell it may be useful to ask which of the last four types of fuel cells this could be. (We had access to a small formic acid fuel cell. Model fuel cell cars are available for between $70 - $150.) Hopefully the students notice that Solid Oxide and Phosphoric Acid fuel cells require temperatures in the 200 – 600 degree Celsius range to operate efficiently. Temperature is just one of the factors that effect performance of a fuel cell. Components used, especially the catalyst, additionally the type and purity of the fuel used and the amount of oxygen available can also contribute to efficiency or lack thereof. Go back to the main menu. Ask the students if from what they have seen they can think of: 1. Possible uses for a fuel cell 2. Advantages and disadvantages of a fuel cell 3. Differences between a fuel cell and a standard DC battery

8 As you go through the “What is a fuel cell” slides try to fill in the blanks for the questions that you have posed. (See appendix for possible answers.) Go back to the main menu. A good video to pull much of this information together is found at “Fuel Cells, Driving the Future”. It is approximately 13 minutes long.

See appendix for activity extensions.

Appendix:

Projects If the equipment is available there are a variety of projects and lab activities that can be incorporated into the module.

1. Fuel Cell car

There are a variety of toy fuel cell powered cars that can be purchased online for $70-$150. They have solar panels that allow electrolysis to occur in water to separate hydrogen and oxygen. The car then takes the hydrogen and oxygen and powers a vehicle through a fuel cell. This could be used in a classroom to demonstrate

9 the process of electrolysis as well as showing how the fuel cell works. You also now have a small PEM fuel cell that students can now see and touch. You also now have a small solar panel that may be used for other projects.

2. Paper Towel Fuel Cell

Material Cathode- Pt mixed with water and ink Anode- Pd mixed with water and ink Paper towel Sulfuric acid Formic Acid 2 pipettes 2 paint brushes 1 voltammeter

Another project that can be adapted for the lesson is a paper towel fuel cell. The material needed is a vial of Pt (platinum) mixed with ink and water for the cathode, and another vial of Pd (palladium) mixed with ink and water for the anode. Students will paint these onto opposite sides of a paper towel cut 1 cm by 4cm. The cathode and anode should each be painted on as .5cm - .75cm diameter circles on opposite sides of the paper towel as far apart as possible. Different paint brushes should be used to avoid contamination of the cathode and anode. After the cathode and anode are painted on they should be given around 2 minutes to dry.

The students will next need a vial of formic acid, sulfuric acid, and a voltammeter. After the cathode and anode have time to dry students should drop two drops of formic acid on the anode with a pipette. A student should then place the voltammeter on the fuel cell, placing the negative cord on the anode and positive on the cathode and hold it there. The voltammeter should be reading zero at this point.

10 Another student should then take a different pipette and drop the sulfuric acid on the space in-between the cathode and anode (starting right next to the cathode) until it is touching both. This acts as the PEM or cell membrane. Students should be careful that the sulfuric acid just touches the edge of the cathode and anode.

When the sulfuric acid touches both the anode and cathode the voltammeter should jump up to around .7 to .8 volts. If the anode and cathode were not allowed to dry properly, or some type of contamination were to take place then the voltage reading will vary. It may be beneficial at this stage to ask the students again to point out the various parts of the fuel cell (anode, cathode, catalyst, membrane), and how the energy is flowing (protons along the sulfuric acid trail, and electrons through the wires). There are several extension activities that could be added to this experiment. If there is enough time students should be allowed to experiment with different types of paper to use instead of paper towels. Students could also use a different fuel other than formic acid or a different cell membrane other then sulfuric acid to see what happens.

Possible answers to: 1. Possible uses for fuel cells Transportation (automobiles, busses, trains) Submarines Batteries for portable electrical devices Electricity off the grid Electricity for space flight Micro fuel cells implanted in the body

2. Advantages

Waste product is H20 As long as you have fuel, you have power Quiet

11 Hydrogen is plentiful Many different fuels can be used to get the hydrogen Different types of fuel cells and solve different types of problems Fuel cells contain no parts that are harmful to the environment should they need to be disposed of

Disadvantages Storage of hydrogen Hydrogen must be taken from some other element*** Building a hydrogen infrastructure will be costly Fuel cells (especially small ones) are not cost effective at this point

CONVERSION S - ALTERNATIVE ENERGY: (Questions from a handout of Dr. Zollars) 1. In the year 2006 worldwide energy consumption was approximately 474 Quads. That same year energy consumption in the U.S. was 97 Quads. What per cent of the world’s energy consumption did the U.S. account for in that year?

2. The world’s population on July 17, 2008 was 6.83 billion people. The U.S. had a population of 305 million people at that time. What per cent of the world’s population lives in the U.S.?

3. Look at the formula page and determine how much of each resource we use to create 97 quads of energy. ( For example, how much petroleum, wind, solar, …)

4. An average railroad boxcar is approximately 51 ft X 10 ft X 12 ft and can hold 150 ton of coal. If we want to supply 97 Quad of energy, how many railcars would be necessary? (Bituminous coal has a heating value about 12,500 BTU/pound.)

12 5. Design a container that will be able to hold all of the coal needed for a year in problem number 4. Be sure to include the dimensions of your container.

6. Hydrogen has a heat of combustion of approximately 60,957 BTU/pound. How many tons of hydrogen would have been needed to supply all of our energy needs in 2006? (The US consumption of energy for transportation is 28 quads.)

7. Gathering our hydrogen from water (to avoid greenhouse emissions) through electrolysis will require electricity. If our electrolysis process has an efficiency of 78% it will require 50 KW-hr to produce 1 kg of hydrogen. If we where to use hydrogen to fuel our transportation system, how many MW of electricity would we need?(In 2006 the total electrical generation capacity in the U.S. was 1.07 X 106 MW.)

8. Grand Coulee produces 6840 MW of electricity. How many Grand Coulee’s would be necessary to supply the energy to convert our transportation system to hydrogen?

9. There are currently 104 licensed nuclear power plants in the US with a total generation capacity of 2.0 X 105 MW. How many new nuclear plants (assuming an average production per plant) would be needed to convert our transportation system to hydrogen?

10. Based on what you have learned in the project, and the conversion questions from above, discuss the feasibility of transferring all of our energy needs to any one source of energy.

11. What do you think the U.S. should do to meet the future energy needs?

13 FUEL CELLS:

1. A cell phone requires 3.8 V @ 1 amp. You have 1 cm2 fuel cells that will operate at .6 V @ 1 amp/cm2. If you connect your fuel cells in series, how many will be needed to power the phone?

2. A fuel cell will operate at .6 V @ .8 amps. What is the measure of the resistance?

3. The cost for Platinum nanopowders used for the catalyst on the anode and cathode sides is $80 per gram. Typically one would use 6 to 8 mg/cm2 for one side. The cost for the membrane is approximately $175 for a 30 cm by 30 cm section. Given the costs of the catalyst and membrane find the cost of a fuel cell in problem #1.

14 4. Use the graph shown to determine the Voltage for the given fuel cell running at 0.6 amps/cm2.

V I Plot

1.4 1.2 1 V volts 0.8

0.6 0.4 0.2 0 0 500 1000 1500

I milliamps/cm2

5. Again, using the graph, find the cost of running a device that requires 5.3 V @ 1 amp. You will need to determine how many amps to gain the voltage you will need, the size of your fuel cell, and how many fuel cells will be needed (in series).

6. Pick a house hold appliance, such as a laptop or game boy and look up how much amperage and voltage is needed to run it. Next figure out what is the least amount of fuel cells needed to power it. You have 1 cm2 fuel cells that will operate at .6 V @ 1 amp/cm2.

15 DO WE NEED ENGINEERS?

1. In 2004 – 05 1.4 million juniors took the PSAT, 16.3% of the males and 1.9% of the females planned on pursuing engineering as a career. Assume that there is an equal ratio of female and male test takers. Assuming that 70% of each group actually gains degrees in engineering, how many new engineers could we expect from this group when they graduate from college?

2. Of the group described in problem number one, 8.3% of all those who took the PSAT planned to pursue engineering degrees. What does this tell you about the gender split of those taking the PSAT that year ?

16 3. In 1984 the number of freshmen entering college and enrolling in engineering was 1.5 X 105. In 2004 that number was 1.34 X 105. What was the percent difference in enrolling engineers ? Is this a percent increase or decrease?

4. In 1984 there were approximately 1.35 X 106 freshemen entering college (total), and in 2004 there were 1.8 X 106. Assume that enrollment each year grows at a constant rate. Find the percent of growth per year.

5. What if the number of enrolliing engineers grew at the same rate each year as total enrollment. How many freshmen engineering students should we have expected in 2004 ?

6. Use the table (information from 2006) to determne the (engineer graduate)/(total population) ratio for each country.

Country Eng. Degrees granted Total Population Japan 98,431 127.8 million Russia 82,409 141.7 million Souith Korea 69,420 48.9 million U.S. 60,639 299.0 million Taiwan 41,947 22.8 million

7. In 2005 a total of 7,276 engineering doctoral degrees were awarded. 4,405 of those degrees were granted to foreign nationals. What per cent of doctoral degrees were earned by U.S. citizens ? Twenty per cent of the U.S. citizen doctorates were awarded to women. How many women earned doctorates in engineering that year?

THE BIG QUESTION :

Use 3 – 5 paragraphs to discuss alternative enery’s role in our world in the future (25, 50, 100 years your choice). Site at least 3 specific expamples from the power point, and use math that you have developed from asnwering the assessment to help to support your position.

17 Formula Page

Conversions 1 Quad = 1015 BTU 1 Quad = 1.05 X 1018 Joules 1 Quad = 2.9 X 1011 KW h (kilo watt hours) 1 Quad = 2.5 X 105 KTon of TNT 1 inch = 2.54 cm 1 kilogram = 2.2 pounds 1 mile = 5280 ft

Metric Prefixes T tera 1012

18 G giga 109 M mega 106 K kilo 103 m milli 10-3  Micro 10-6 n nano 10-9 p pico 10-12

Electrical information : Circuits in :

Series :Vtotal = V1 + V2 + … + Vn (amps remain constant)

Paralell : Itotal = I1 + I2 + .. + In (volts subject to V = IR)

V = IR (voltage = amperage X resistance)

Watts = VI (Watts is a measure of enrgy, most often thought of over time, KW hours or Kilowatt hours for example)

Energy Sources in the US in 2006 . Source % of Total Energy Demand % of Electrical Demand Petroleum 39.4 3.4 Natural Gas 23.9 16.9 Coal 22.6 51.2 Nuclear 8 20.7 Biomass/biofuel 2.9 1.6 Hydroelectric 2.76 6.6 Geothermal 0.32 0.37 Solar 0.007 0.01 Wind 0.006 0.16

19 Answer Guide Alternative energy 1. 20.46% of the world energy demand. 2. 4.47% of the world population. 3. Pet 38.218 NatGas 23.183 Coal 21.922 Nuke 7.76 Bio 2.8 Hydro 2.68 Geo .31 Solar .00679 Wind .00582 4. 25,866,666.7 coal cars.

20 5. Volume is 1.583X10 11 ft 3 any container that matches will work . If you make a cube it would be 5410 ft on each side (note that this over a mile tall) 6. 229,696,472 tons of hydrogen is needed. 7. 926,940 MW 8. 135.5 dams 9. 482 Nuclear Power plants 10.Answers may vary. 11. Answers may vary.

Fuel Cell Questions 1. 7 fuel cells 2. .75 ohms (units optional) 3. for 6 g/cm 2 $8.08 for 8 g/cm 2 $10.32 4. approximately .7 volts 5. Answers could vary, but reading the graph at 1 amp/cm 2 6 g/cm 2 $12.69 8 g/cm 2 $16.21

Engineers 1. 89,180 (We need to change the question so that it says something about assuming the same number of males and female test takers) 2. 81,340 More females took the test 3. 10.67% decrease 4. 33% increase 5. For younger kids who don’t know about exponential functions and logs so that there is just a 33% increase over time it would be 178,667 engineers. For kids who should know that y = ab t it would be closer to 200,000 engineers. 6. Japan .077% Russia .058% S. Korea .13% US .02% Taiwan .18%

21 7. 39.4% 574 women

22 23 Work Referenced Bard, A., Brown, M., Corradini, M., and Mark, J. (2008) What You Need to Know About Energy. National Academy of Sciences.

Bunkley Nick (2008, January 8). G.M.’s Fuel Cell Car Makes a Statement. New York Times.

FC Tec. 2001 – 2008. Concurrent Technologies Corporation. June 2008.

Institute of Chemistry. Hebrew University of Jerusalem. 28/05/2007 http://chem.ch.huji.ac.il/history/grove.htm, June 2008.

Kadt, Maarten. (February 7, 1990). Discarded Batteries Threaten Environment. The New York Times . June 2008.

Dr. Zollars. Alternative Fuels handout