Sustainable Transportation Fuels Curricular Unit for HS Level Students. Key Concepts & Processes

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1 Sustainable Transportation Fuels Curricular Unit for HS Level Students Converting to the use of biofuels, electricity or hydrogen for transportation fuels is touted by many as a solution to our growing energy crisis, which includes a waning supply of oil, global climate change, and increased health effects due to poor air quality in most major cities. But are these fuels really viable solutions? The hydrogen or biofuel economy must be understood and addressed before our society is ready for change. Understanding the implications of changing our transportation fleet is a very large task that needs to be understood in great depth before one can ask a society to readily accept paying more for this technology. This unit uses a systems perspective to consider the pros and cons of various vehicle/fuel systems. Participants investigate transportation fuel needs, complete activities and research to understand the value, risks, and process of implementing alternative fuels, make hydrogen and biofuels, build and test a fuel cell, and analyze these systems from a lifecycle perspective. Three options are available for a culminating project. In all cases, the students must use their newly gained perspective on the problem and alternative solutions in order to recommend and defend a suitable way to move forward with improved sustainability of our vehicles and fuel systems. Key Concepts & Processes 1. Based on our present understanding of the amount of economically extractable crude oil, petroleum fuels will not be sufficient to meet future demands. 2. Fuel cell and hydrogen production technologies, electric cars, and biofuels production are rapidly advancing and are proposed for use in transportation vehicles. 3. Fuel cells and battery operated electric vehicles operate based on an electrochemical reaction to generate electricity that is used in an electric motor to power the car. 4. Energy conversions require systems and subsystems, more components result in lower efficiency. Efficiency can increase as technologies improve. 5. Hydrogen, electricity and biofuels must be generated; these processes require energy. 6. Choosing an alternative fuel source requires an understanding of the entire fuel/vehicle system and the trade offs from many different perspectives. 7. Emissions from hydrogen use in a vehicle are very clean, although there are emissions associated with energy consumption to make the hydrogen. 8. Energy use and environmental impacts depend on both the source of energy as well as the conversion processes. 9. Changes in our future transportation vehicles and fuels will require technological advances, but also social, business and policy changes as well.

2 Sustainable Transportation Fuels Unit Overview (~3-6 week unit) Lesson 1: Introduction of the general problem and specific project (2-4 days) Intro to general problem Video (End of suburbia or Who Killed the Electric Car) (discussion questions) Project statement introduction and problem solving approaches Lesson 2: Why we need alternative fuels (3-4 days) Environmental and natural resource impacts (group research and presentation) Carbon footprint analysis (discussion questions) Lesson 3: Fuel cell, Batteries and hydrogen production (~4-8 days) Introduction Batteries (discussion questions) Fuel cells basics and assembly (discussion questions) Testing fuel cell (with lab report) Electrolysis (discussion questions) Hydrogen infrastructure (brief presentation) Lesson 4: Biofuels (3-4 days) Introduction (with optional homework) Making biodiesel (discussion questions) Testing biodiesel (lab report) Lesson 5: Systems Perspective (2-3 days) Efficiency (discussion questions) Lifecycle assessment (brief presentations) Project completion (report and formal presentation) (2-5 days)

3 Assessing the Curricular Unit This unit has been through rigorous testing to evaluate the student gains in energy literacy possible through this type of project. The results have been reported in paper and presentation at the American Society of Engineering Educators. Abstract Using a Real-world, Project-based Energy Module to Improve Energy Literacy among High School Youth 1 A project-based energy module has been taught for five consecutive years in a high school environmental science class as part of an NSF GK-12 outreach program. The module brings students through an exploration of problems and potential solutions related to automotive transportation, a relevant topic for the average American teenager. Students investigate problems related to our current fossil fuel based transportation system including environmental impacts and limited fuel supplies, and explore potential solutions that include alternative modes of transportation and fuels as well as lifestyle changes. Changes in students energy literacy, a broad term that includes a citizenship understanding of energy issues as well as attitude and behavioral aspects, have been assessed over the last three program years using a quasiexperimental, mixed methods approach that includes both quantitative and qualitative measures. The quantitative measure consists of a written Energy Literacy Survey that has been developed and validated as part of this research. Qualitative data, collected through a combination of questionnaires, focus group interviews, and classroom observations, add depth and understanding to the quantitative results. Analysis of the quantitative survey over three consecutive years indicates that students show significant improvement in energy-related knowledge (scores increased from 60% pre to 68% post), feelings of self-efficacy related to energy issues (71% pre to 75% post), and energy consumption behaviors/intentions (63% pre to 69% post). Similar gains reported by a comparison group, available for only one study year, indicate that students may be influenced by experiences outside the classroom and point to the need for additional data to clarify the results. When asked to self-assess their learning, 84% of the students said they learned a lot or a quite a bit about energy issues. Responses to open-ended questionnaire items indicate that the course increased (81% of the) students awareness of the need to conserve energy; 54% indicated that they are more aware of the implications of their own energy use on the overall energy problems; 20% say they are more aware of, and troubled by, Americans overconsumption of energy resources; and 60% reported positive changes in their energy consumption behaviors. These preliminary results suggest that the project-based curriculum is effective for promoting student learning, but the generally low knowledge scores indicate the need for continued efforts toward wider implementation of energy education programs. 1 DeWaters, J.E., S.E. Powers, Using a Real-world, Project-based Energy Module to Improve Energy Literacy among High School Youth. In: Proceedings of the 116th ASEE Annual Conference & Exposition, paper AC (Austin TX, June 2009).

4 Student Assessment [needs completion]

5 Key Terms (Not complete or checked) Anode: positive electrode Atmosphere: gaseous layer surrounding a planet; the whole mass of air surrounding the earth. Batteries: storage devices that convert chemical energy into electricity Byproducts: other products produced from the reaction Carbon dioxide concentrations: the concentration of carbon dioxide (mass/volume) in the earth s atmosphere. Carbon footprint: a measure of the impact a certain activity has on global climate change, in terms of CO 2 emissions. Catalyst: a substance that increases the rate of reaction without being consumed in the process Cathode: negative electrode Ecological footprint: a measure of the world s resources (land, air, water) required to support a particular lifestyle. Efficiency: The ratio of the work done or energy developed by a machine, engine, etc., to the energy supplied to it, usually expressed as a percentage. Electrode: conducting element that emits or collects electrons or ions Electrolysis process wherein electrical power is used to split water into hydrogen and oxygen gases Electrolyte: medium for transporting appropriate ions Electrolyzer: a device used to produce hydrogen and oxygen from water Energy carrier a material used as a fuel that must be generated using a primary energy source. Emission factor: amount of pollutant emitted per unit of fuel consumed. Feedback mechanism A means by which the outcome of a process affects the process itself, creating a loop. Positive feedback is when the loop leads to increased output or a reinforced tendency, whereas negative feedback leads to a reduced output or tends to dampen a tendency. Fossil fuel: non-renewable natural resources that include coal, oil, and natural gas. Fuel Cell: general: electrochemical devices that uses an electrochemical reaction to convert chemical energy into usable for of energy (e.g. heat and electricity); specific: a unit designed to generate electricity from the reaction of hydrogen with oxygen through a proton exchange membrane (PEM) Fuel Economy: a measure of fuel efficiency e.g. miles traveled per unit of fuel.

6 Global warming: increase in average global temperature. Some of the increases are due to build-up of gases such as CO2, NO2, and chlorofluorocarbons in the atmosphere as a result of industrialization. Global climate change: changes in the earth s climate due to increased concentrations of greenhouse gases in the atmosphere. Greenhouse: glass- or plastic-paned structure with a wood or metal frame. Temperature and humidity can be controlled for growing plants out of season. Greenhouse Effect Trapping and build-up of heat in the atmosphere (troposphere) near the Earth s surface. Some of the heat flowing back toward space from the Earth's surface is absorbed by water vapor, carbon dioxide, ozone, and several other gases in the atmosphere and then reradiated back toward the Earth s surface. If the atmospheric concentrations of these greenhouse gases rise, the average temperature of the lower atmosphere will gradually increase. ( ) Greenhouse Gas (GHG) Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases include, but are not limited to, water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), ozone (O3 ), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). ( ) Hydrogen Lightest element known to man. Consists of one electron and one proton, a gas at room temperature, exists in diatomic state Hypothesis: an assumption made to account for or relate known facts. Infrared radiation: the portion of the electromagnetic spectrum that extends from the long wavelength, or red, end of the visible-light range to the microwave range. Inverter: a device that changes direct current (DC) to alternating current (AC) Peak oil: the point that identifies maximum global oil production after which the rate of production (amount of oil produced per year) declines. Polar ice cover: area of ice covering the earth year-round at the north and south poles. Prototype: a working model (usually small) of a full-sized system. Used to study behavior when it is impractical to work with the real system. Reformer: a device that converts hydrocarbons into a mixture of hydrogen and carbon dioxide gases for the fuel cell

7 Sustainability and the Future of Transportation Curriculum Worksheet To summarize key points Date Lesson Topic Important items learned, especially regarding final project Intro - Fuels of the Future / Green concept cars Why is it that some cars cannot be rated using miles per gallon (mpg)? Global issues activity What environmental and natural resource issues should be considered when evaluating sustainable transportation systems? Carbon footprint activity What can a Carbon Footprint tell us about your transportation energy use? How can you use this to evaluate the value of increased conservation or efficiency? Intro Fuel cell cars Why is hydrogen considered a clean fuel? Intro Fuel cell cars What developments are required to make H 2 powered vehicles practical? Hydrogen production and infrastructure What are the trade-offs between large and small scale H 2 production? Biofuels introduction What are a few reasons why some people strongly oppose biofuels?

8 Biofuels testing When is it important to know the heat value of fuels, as well as the volume? Efficiency activity How can efficiency be defined? Are our vehicle systems very efficient now? Efficiency activity What does thermodynamics tell us about energy conversion processes? Lifecycle assessment activity What are some important issues that you may have overlooked before when considering transportation options? Lifecycle assessment activity What is a systems perspective? How is it used to compare different fuels?

9 URL All unit and lesson plans for this unit are included at Owner Office of Educational Partnerships, Clarkson University, Potsdam, NY Contributors Susan Powers, Jan DeWaters, and a number of Clarkson students in the K-12 Project Based Learning Partnership Program. Contributions over several years from the following are acknowledged (in chronological order): Patrick Schalk, Samedy Chhoun, John Bean, Tim Sharac, Mellissa Richards, Mark Venczel, and Amy Wormsley. This unit was developed under National Science Foundation DTS and GK-12 grants No. DUE and DGE These contents do not necessarily represent the policies of the National Science Foundation, and you should not assume endorsement by the federal government. Copyright Copyright 2009 by Clarkson University, Potsdam NY Version: August 2009