Implementation Of A Fuel Cell Laboratory

AC 2009-2035: IMPLEMENTATION OF A FUEL-CELL LABORATORY Homayoon Abtahi, Florida Atlantic University Ali Zilouchian, Florida Atlantic University Page 14.689.1 © American Society for Engineering Education, 2009 Development of a Prototype Fuel Cell Laboratory* Abstract Florida Atlantic University has recently developed a prototype interdisciplinary undergraduate fuel cell (FC) laboratory. The new laboratory addresses simple and effective approaches for the implementation of fuel cell technology and its applications through the innovative industrial design techniques, incorporation of real-time sensory interfacing and other applicable industrial advances. The implementation phase of the laboratory has been recently achieved in collaboration with a leading industry with over 15 years experience in design, fabrication and implementation of fuel cells in both stationary and mobile applications. Students from electrical, mechanical, ocean and computer engineering are currently benefiting from opportunities the laboratory provides in design, experiment and simulation of fuel cells. The laboratory consists of a prototype experimental station. The station contains three microcomputer, three Data Acquisition boards, several sensors and actuators, and eight experimental setups. Authors have recently offered a new course entitled “Introduction to Fuel Cell Technology” in conjunction with the FC laboratory. In addition, multi-disciplinary student groups from senior design classes are utilizing the lab for FC design projects. It is anticipated that the current development of the new laboratory will have a direct impact on undergraduate education by creating a focal point for interdisciplinary learning, a balance between theoretical and hands-on experience in undergraduate teaching, and application of these educational tools in a vibrant technology sector. The evaluation plan for the course materials focuses on three general areas. The first focus is on the assessment of the course modules. The second focus is related to student-identified strengths/weaknesses of the course/modules. Finally, the third focus is to document the course/curricular refinements resulting from the evaluative data obtained by end of spring 2008 semester. Introduction The population of the United States is projected to increase from the current level of 303 million to 438 million by the year 20501. Only 0.2 % of all energy consumed comes from solar and wind generation, and only 3.3% is derived from bio-fuels and biomass2 . The commitment of the new US administration to lead the US to a new era of less dependence on energy imports, and a serious move to renewable sources of energy presents great opportunities for job creation and economic development. Jobs that are based on home-grown green energy supplies may be one of the many anchors that may stabilize our nation and help the economic turn-around. Page 14.689.2 The technical and scientific challenges to provide reliable energy for the nation in a short 30 year period are enormous tasks, and especially so when combined with strategic and recent economic concerns. It is clear that as part of the mix of energy sources necessary to deal with these challenges, solar and hydrogen fuel cells will play critical or even a central role. The US Department of Energy, as well as a number of the national laboratories and academic institutions have been aware of the importance of solar and hydrogen for some time. Recently, car manufacturers, transportation experts, and even utilities are paying attention to this vital source of energy for the future. The universities need to play an even more important role in addressing not only the research component of the transition from fossil fuels to sustainable sources of energy, but, the educational aspects. This role includes a wide range of tasks that include general education requirements at one end of the spectrum to specific retraining needs at the other. This paper addresses the educational, and to some extent the information dissemination component of a recent NSF project related to fuel cell technology by authors. The past fifteen years has seen an emphasis in advancing fuel cell technology to enable decrease reliance on fossil fuels3. Toward this end, a significant amount of governmental and industrial resources have been focused on developing Proton Exchange Membrane fuel cells (PEMFC) as a “cleaner” more efficient alternative to existing power generation technologies. PEMFCs convert chemical energy directly to electrical energy with conversion efficiencies approaching 60% 4-7. In addition, the only bi-product of reaction is water, which makes the PEM very attractive from an environmental standpoint. Foreseen applications of PEM fuel cells are widespread ranging from automotive, aviation, space, marine, military and stationary power production to name a few 8-10. The technology is suited to provide for power demands from a few watts up to about 300kW11. Some of the major advantages of PEM fuel cell over other fuel cell technologies are the low operating temperatures and quick startup. Even though the flexibility of the PEMFC design makes this type of fuel cell an ideal candidate for use in a variety of applications, several areas within the technology need to be advanced to make them a practical and cost effective solution8-12. Issues associated with water management, membrane longevity, and cost need to be addressed in order for the PEMFC to be seriously considered as a viable alternative to present day carnot-cycle/heat engines. As a result, a lot of activity within the fuel cell community is centered on improving membrane and electrode materials, developing methods for managing product water levels and implementing novel manufacturing techniques to reduce cost 12-16. During the last few years, several fuel cell research centers have been created at the universities around the United States. However, most of these centers have developed their activities related to the graduate level research. Although, there are a few activities and undergraduate projects related to fuel cell at the undergraduate level, it appears \none of these activities are directly comparable with the project described herein. The development of the laboratory addresses existing gap between theory and practice at the undergraduate level. Therefore, it is essential that today’s undergraduate students be exposed to the fundamental operation of PEM fuel cells, their varied applications and the issues associated with their widespread use. It is anticipated that the full development of the materials could be utilized by other institutions around the nation. Curriculum Development Page 14.689.3 An introductory fuel cell course (EML 4930/EEL 4930), has been developed as part of the project, which has intended to provide a fundamental understanding of present fuel cell technology, its applications and area of improvement necessary for successful implementation. The course is a 3 credits senior elective course open to students from various departments within the college of engineering. A portion of the lecture course covers the premise behind the operation of a fuel cell and provide a survey of prominent fuel cell technologies, their applications, advantages and disadvantages. The remainder of the class focuses on the PEM fuel cell, its fundamental operation, basic design, components, operating conditions, performance, applications and prevalent system designs. A background of the electrochemical and thermodynamic processes associated with PEMFC are addressed as well as a review of basic designs and components used. Major components such as membranes, electrodes, catalysts, gas diffusion layers, collector plates, busplates and endplates is covered to provide a fundamental knowledge of present materials. A substantial time is spent reviewing operating conditions and their effects on fuel cell performance. Effects of operating pressure, temperature, reactant gas humidification, product-water management and heat removal is also discussed. Commonly used methods for identifying causes of maladies and appropriate remedies are also examined. Considerations necessary for the implementation as well as sizing of a fuel cell stack to a particular application are discussed. This will also consist of a review of electrical design considerations necessary to meet both DC and AC power requirements. An overview associated with the connection of fuel cell stacks in series, in parallel or in conjunction with batteries is provided. Three main system configurations are discussed, pure hydrogen/oxygen, pure hydrogen/air and reformate/air. Both advantages and shortcomings are addressed and areas of improvement reviewed. In order to advance fuel cell technology, the capability to testing and evaluating new designs is critical. Without proper testing facilities very little progress can be made in advancing a particular design. The design and development of fuel cells greatly depends on constructing hardware and then evaluating it under expectant environmental conditions. It is nearly impossible to come up with a fuel cell design that works as intended without proceeding through various testing and redesign iteration. United Technologies Inc., and Teledyne Energy Systems currently have several fuel cell configurations that exhibit excellent performance17-19 . These design techniques can provide exceptional stability even at current densities greater than 600 mA/cm2. Teledyne fuel cells are well known for their high power densities and superb cell-to-cell voltage consistency (typically less than 10 mV, even at high current densities) under various operating conditions 18,19 . The know-how necessary to achieve this level of performance is lacked by most other fuel cell developers due to the immense hardware configurations inherent in designing a fuel cell and the time required to iterate to a final design20-22. Designs such as the model TESI NG2000™ have reached a point in development that allow large-scale production methods to be sought out in earnest. This has largely been made possible by over 15 years of refining designs through testing. Page 14.689.4 The multi-disciplinary and the inter-disciplinary aspects of fuel cells make them ideal teaching tools. Design and analysis of fuel cells involve the understanding of electrochemistry, thermodynamics, fluid flow and heat transfer, system dynamics, electronics and controls on both theoretical and experimental levels. Mechanical, electrical, material science and computer science students can all work together in a unified approach to modeling, simulation, and testing of fuel cells. The College of Engineering at FAU has for several years supported a multi-disciplinary approach to engineering education. The senior year set of two design courses involve students from all engineering departments working together in design and fabrication of student projects. The concept of using fuel cells as the center of a cooperative course between electrical and mechanical engineering grew out of a cooperation between respective faculty members of these two departments. The tools needed for analysis, simulation, and testing of fuel cells are common to both departments and include: system modeling and tools as such as Matlab’s SimulinkR, an extensive data acquisition system and the utilization of National Instrument’s LabviewR hardware and software. These common threads between the students from mechanical and electrical engineering departments were used to form a cohesive class of multi-disciplinary individuals working on a common project. Laboratory Modules and Project Evaluation The students in the fuel cell class were exposed to Fuel Cell fundamentals. Department of Energy (DOE) handbook on fuel cells2 was made available on the class Blackboard site as well as a number of other references. Once the students had a basic familiarity with fuel cell electrochemical basics and general design principles, they were grouped into teams of three to four. To strengthen the multi-disciplinary nature of the course, each team was required to have at least one mechanical and one electrical engineering student. Each team was then required to study and evaluate a major aspect of fuel cell research, development, design, safety or marketing. The flexibility for topic choice created interest and excitement in the classroom, and led to informative, educational, and a state-of-the art discussion of emerging and innovative fuel cell technologies23-37-. For the spring 2006, more than 40 students have enrolled for the EEL 4930 or EML 4930 course. The students' survey has provided the PIs a great feedback to refine the materials as well as the laboratory experiments. More than fifteen team projects were completed during Sp. 2006 semester. For the spring 2007, 29 students were enrolled for the course. The students were divided into 13 different groups for the experimental part of the project. Due to the Laboratory limitation, a cap was placed for the Spring 08 semester. 14 students registered for the course for the spring 08 semesters. The content of the course was revised according to the assessment plan. For the first-phase course evaluation, a course-based assessment instrument has been designed to determine fundamental student understanding of PEM fuel cells, their varied applications, and issues associated with their use. Ten(10) questions have been distributed to the students at the end of each semester that course has been offered for the past three years. The first part of the assessment has focused on (1) integration of the lecture and the laboratory (2) labview and data acquisition, (3) simulik modeling of the fuel cells (4) the data collection of the commercial fuel cell (5) modeling of the fuel cell based on the laboratory data, and (6) completion of a system design and final project. The second part of the assessment has focused upon student-identified strengths/weaknesses of the course/modules. In sequel, the assessment results have been utilized for the course/curricular refinements. Twenty-two (22) students provided the survey for spring 2007. Eleven (11) students returned the survey papers for spring 2008. In addition, 5 different surveys were conducted for teaching assistants. Below is a brief summary of the student's feedback based on the above described modules: Page 14.689.5 (1)Students were generally pleased with the integration of the course materials and the laboratory. For the Spring 07 semester, 89% of the students approved the integration of the lecture and the laboratory strongly, and 9% disapproved of the concept. For spring 2009 survey, all students strongly approved the integration of the course and the laboratory. (2) The four (4) Simulink modeling experiments were very useful to understand the mathematical concepts and the modeling of the PEM fuel cell. 82% of the surveyed students highly approved the simulink experiments for the spring 07 semester. All the students for spring 08 semester thought the simulink experiments were very useful. (3) The three Labview projects have provided the students with much better understanding of the instrumentation interface and data acquisition procedures. However, only 59% of the students have approved the approach for the Labview experiments, where 39% thought major improvements were needed. In sequel, the students' suggestions were integrated for the spring 08 semesters. All of the students were positive related to the Labview experiments. They thought it was a very useful tool for real-time modeling and control. (4) Majority of spring 07 survey students were pleased with the lab experiments with Nexa Fuel cell (68%). However, more stations with variety of fuel cells were needed in order to accommodate the enrolled students in the lab. For spring 08, more stations were added with limited number of students for each lab session. (5) Modeling of the Nexa based on the collected lab data were revised based on the TA's and student's suggestion. The students' survey shows 100% approval for the Nexa experiment for the sp. 08 semesters. (6) All students for spring 06, 07 and 08 were pleased with the final project modules. During spring 2007, thirteen (13) different team projects were completed by the students in various subject related to PEM fuel cells. During 2008, eight (8) different projects were completed. The students were very pleased with formal, informal, team learning and self learning of the projects. Students were required to present their final project. They were also required submitting a formal report for each project. The students have worked as a team in order to accomplish each of their tasks. Each team prepared a written final report describing their projects. In addition, each team was required to present the project to the entire class. Finally, representatives from a spectrum of local industries, including Motorola, Teledyne Inc. and Enerfuel Inc. have been invited to visit the new laboratory several times. Their comments and suggestions have been utilized to modify the on-going activities at the laboratory. Furthermore, peer evaluation of the laboratory program has been conducted by invitation of colleagues from universities especially from the Florida State University Systems including UCF, FSU, and FIU. Such evaluations have been utilized in order to enhance our program as well as to provide a vehicle for our national visibility in this area. Page 14.689.6 Figure 1: Implementation of Single Stack FC Figure 2: Single Stack FC Page 14.689.7 Figure 3: Ballard NEXAR 1.2 kW fuel cell test station Summary Student reaction thus far has been exceptionally gratifying. There is a sense in the classroom that this is a real opportunity for learning. The chemistry between the students and the teachers reveals the special bond that develops when a group of interested students and teachers come together for a common goal. While projects and lab assignments are graded, it is clear that most of the students in this class are not attending merely for a grade. One of the most interesting observations in this class is that when learning is task oriented, much better results are achieved. This is particularly evident in the students’ attitude toward modeling and instrumentation software packages. Because the students are aware that they will use the software in the upcoming experiments involving the fuel cells with their specific lab assignments, there is improved attendance, retention, and nearly 100% compliance with assignment goals. As compared with the authors’ experience in for example Experimental Methodology which also uses the Labview packages but for generic experiments, there appears to be a better response in the goal oriented fuel cell class. In summary, the Fuel Cell Course has proven to be a tremendous tool in multi-disciplinary learning, in the teaching of modeling and instrumentation software, covering the fundamentals of fuel cell technology, and hands on training of students with PEM fuel cells. Based on evaluation outcome and accomplishments of the project, the prototype system can be elevated to full-scale development and implementation in various institutions around the nation. Page 14.689.8 References 1. Population Reference Bureau Web site: http://www.prb.org/ 2. DOE, Energy Efficiency and Renewable Energy Website: “http://www.eere.energy.gov/” 3. F. Barbir: Recent Progress and Remaining Technical Issues in PEM Fuel Cell Development, World Hydrogen Energy Conference, WHEC XIII, Beijing, China, June 2000. 4. M. Fuchs, F. Barbir and M. Nadal: Performance of Third Generation Fuel Cell Powered UtilityVehicle #2 with Metal Hydride Fuel Storage, European Polymer Electrolyte Fuel Cell Forum, Lucerne, Switzerland, July 2001. 5. M. Fuchs, F. Barbir and M. Nadal: Fuel Cell Powered Utility Vehicle with Metal Hydride Fuel Storage, Globe Ex 2000 Conference, Las Vegas, Nevada, July 2000. 6. J. Larminie and A. Dicks: Fuel cell systems explained, John Wiley & Sons, Ltd, West Sussex, England, 2000. 7. M. Williams, D. Rastler and K. Krist: Fuel Cells: Realizing the Potential, 2000 Fuel Cell Seminar, Portland, Oregon, October 2000. 8. D. Schmal, J. Bastianen and I. 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Ho: Challenges for Transportation Fuel Cells-Fuel Processing and Cost, 2000 Fuel Cell Seminar, Portland, Oregon, October 2000. 15. Y. Guezennec, G., Rizzoni and etal: Supervisory Control of Fuel Cell Vehicles and its link to Overall System Efficiency and Low–level Control Requirements; Proceedings of 2003 American Control Conference, Denver, Colorado, June 2003. 16. P. Rodatz, G. Paganelli and L. Guzzella: Optimization of Fuel Cell Systems through Variable Pressure Control, Proceedings of 2003 American Control Conference, Denver, Colorado, June 2003. 17. J. Eborn, C. Haugstetter, L. Pedersen and S. Ghosh: System Level Dynamic Modeling of Fuel Cell Power Plants, Proceedings of 2003 American Control Conference, Denver, Colorado, June 2003. Page 14.689.9 18. M. Fuchs: Teledyne Energy Systems Inc.: Development of Advanced, Low-cost PEM Fuel Cell Stack and System Design for Operation on Reformatting, 2001 Annual Progress Report: Fuel Cells for Transportation, U.S. Department of Energy: Energy Efficiency and Renewable Energy Office of Transportation Technologies, pp. 106-108, Washington, D.C., 2001. 19. M. Fuchs and F. Barbir: Energy Partners L.C.: Development of Advanced, Low-cost PEM Fuel Cell Stack and System Design for Operation on Reformatting Used in Vehicle Power Systems, Annual Progress Report: Transportation Fuel Cell Power Systems, U.S. Department of Energy: Energy Efficiency and Renewable Energy Office of Transportation Technologies, pp. 79-84, Washington, D.C., 2000. 20. H. Abtahi, P. Das and M. Fuchs: Final Report on Fuel Cell Flow Optimization, # PRDA-DE - AC0896NV11986, October 10, 1997. 21. H. Abtahi and A. Zilouchian and F. Fuchs: Design and Implementation of an Intelligent Control Strategy for Fuel Cells, Proceedings of 1998 World Automation Congress, Anchorage, Alaska, May 1998. 22. H. Abtahi, A. Zilouchian, A. and F. Fuchs: Design and Implementation of a Hierarchical Control Strategy for Proton Exchange Membrane Fuel Cells, Proceedings of 37th IEEE, Controls and Decision Conference, pp. 461463, Tampa, FL Dec. 1998. 23. A. Zilouchian, A. and H. Abtahi, Design and Implementation of a Fuel Cell Laboratory, 2008 National Science Foundation CCLI Conference , Washington, D.C., August 2008. 24. A. Saengrung, H. Abtahi and Ali Zilouchian, “Neural network model for a commercial PEM fuel cell system” Journal of Power Sources, Vol. 172, 749-759, 2007. 25. H. Abtahi, and A. Zilouchian, ”Using Alternative Energy Sources and Appropriate Energy Utilization as Teaching Tools for Mechanical and Electrical Engineering Students” 4th Latin American and Caribbean Conf. on Eng. and Tech. (LACCEI), Puerto Rico, 2006. 26. M. Saelzer, R. Messenger, A. Zilouchian and H. Abtahi “Solar-Powered Electric Cart”, Proceedings of 19th Annual Florida Conference on Recent Advances in Robotics, Miami , May 2006. 27. A. Zilouchian, H. Abtahi and A. Saengrung, “Water Management of PEM Fuel Cells Using Fuzzy Logic System”, IEEE Systems, Man and Cybernetic Conference. October 2005. * This project is partially supported by the National Science Foundation(NSF) under the grant #DUE-0341227. Page 14.689.10