Some Factors to Consider in Teaching Renewable Energy in an Undergraduate Engineering Program

Transcription

1 Some Factors to Consider in Teaching Renewable Energy in an Undergraduate Engineering Program Patrick H. Oosthuizen Department of Mechanical and Materials Engineering, Queen s University, Kingston, Ontario, Canada 1

2 Introduction In the teaching of renewable energy to engineering students it is important to stress that an engineer must always consider all sides of the problem at hand and must understand that in arriving at a solution some trade-offs between different requirements and constraints will often be necessary, i.e., that there is often not a single best solution to engineering problems. An understanding of this can be of great importance in dealing with energy related problems. 2

3 World Problems If people are asked about the greatest problems being faced by the world today, the answers are likely to include: Global warming resulting from energy use Shortages of water Increasingly limited supply of fossil fuels Shortages of food Over-population Pandemics 3

4 World Problems (continued) Damage to the ozone layer Pollution of all types Deforestation Poverty War 4

5 Consequences In seeking a solution to one of these problems we must make sure that the solution adopted doesn t exacerbate one of the other problems. This is of course related to our ethical commitment, as engineers, to finding solutions that are of the greatest benefit to our fellow humans. The problem is that the solution that is best for one group may do harm to another group and the consequences of the solution for all groups must be taken into account. 5

6 Example 6

7 Example 7

8 Societal Interaction Energy supply and use is an area where there is an obvious interaction between engineering and society, some of this interaction involving aspects of engineering ethics. This interaction has had both beneficial and detrimental effects on society and it is sometimes not clear whether it is society driving the engineering or engineering leading society that has led to the interaction. 8

9 Societal Interaction (continued) Because of its relevance to solving our energy problems it is important to deal with the interaction of engineering and society in courses on energy. However, since many engineering programs do not address the topic of societal-engineering interaction to an adequate degree and because the energy situation has so many aspects that involve engineering and society interaction, the discussion of societal aspects in an energy course should preferably be broader than that required by the course alone. 9

10 Silly Solutions Students should learn to give adequate consideration to what at first may appear to be silly solutions to our energy problems. Sometimes, albeit rarely, there are useful ideas in these silly solutions. This point can be dealt with, for example, by having student groups discuss, evaluate and comment on proposals similar to the following: 10

11 Silly Solutions (continued) Use large airships that fly well into the stratosphere and have a very large solar panel that is used to charge very large banks of batteries or to generate hydrogen over an extended period. The recharged batteries or the stored hydrogen is then transferred to smaller transport airships for transfer to earth where they are used. The transport airships also deliver uncharged batteries or empty hydrogen storage devices to the generator airship. 11

12 Silly Solutions (continued) Every new road must be built with a network of pipes under it which are used to heat water in summer and cool water in winter. The hot and cold water is stored in separate distributed reservoirs and used to provide heating and cooling in winter and summer. Far more attention must be given to solar chimney generating systems which can be placed in large numbers in the desert areas of the world. Harness the energy in erupting volcanoes possibly by regenerating high temperature heat storage devices by lowering them into the molten lava. 12

13 Problems Students must learn to at least consider the possibility that there may exist unanticipated problems associated with an energy source or energy producing device which appears to be very promising. For example they may be required to consider and discuss questions of the following type: Some claim that noise is produced by some wind turbines that is not sensed by most people but is disturbing to others. It has been claimed that the extensive use of small scale geothermal systems can affect local vegetation and climate by affecting the average ground temperature. 13

14 Learning From the Past In reviewing the present energy situation it is important to consider the factors that have led to this situation. Among the main such factors are: we presently use energy resources that represent the storage of energy over very long periods of time and that deliver large amounts of energy on both a mass and a volume basis we use resources that in the past have been viewed as reliable and widely available we use resources that in the past have had low cost, we use a variety of resources in order to match a variety of needs 14

15 Learning From the Past (continued) We need to remember these factors in searching for means of meeting our future energy needs. We need to remember that we first used the obvious wood that surrounds us as an energy source but that we learned with time to look beneath the surface for other sources. We need to acknowledge that the most obvious solution is not always the best solution. We must examine what has been done in the past to meet our energy needs but we mustn t be limited by past work. We must encourage students to innovatively consider new approaches to supplying our energy needs. 15

16 Energy Storage We must always discuss the need to balance supply and demand variations in the energy sector. It appears that at least for some time into the future our supply system will have to be made up of a variety of resources that together can match supply to demand and/or must incorporate a means of storing energy that will allow the matching of supply and demand. In teaching students we don t always adequately deal with this point and with means of energy storage. 16

17 Other Considerations The following are some other points that should be considered in teaching energy related courses: Deal with meeting energy needs in all sectors. Consider to hydroelectric systems of all sizes. Deal with pros and cons of nuclear energy. Discuss use of a lifecycle approach in the evaluation of energy systems. 17

18 Outcomes When developing a course or program concerned with renewable energy we should ask what characteristics are required of an engineer to be successful in this field. Examples could be: Innovative Open-minded Thinks critically Clearly defines problems and constraints Adopts a system approach Ethical The course should then be structured to ensure that the importance of these characteristics is stressed. 18

19 Other Courses While we need separate courses concerned with energy, attempts should be made to incorporate some discussion of energy related topics into other courses. This could simply be in lectures to illustrate the application of the materials being taught or in could be in examples, assignments, projects or case studies. 19

20 Concluding Remarks In teaching courses on renewable energy to engineering students it seems important not to just teach them about the technology. It seems equally important to teach them about assessing the overall impact of the technology on society. This and other aspects of teaching such courses have been dealt with here. 20