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ENERGY CONVERSIONRenewable Energy TechnologiesSolar (Solar thermal-Photovoltaic)WindBiomassFuel CellsGeothermalWave EnergyHydropowerNuclear
Abdul Makhsud
What is energy?Energy is an abstract concept invented by physical scientists in the nineteenth century to describe quantitatively a wide variety of natural phenomena. David RoseIt is important to realize that in physics today, we have no knowledge of what energy is. We do not have a picture that energy comes in little blobs of a definite amount. Richard Feynman, Lectures on PhysicsEnergy is the capacity for doing work. --Common textbook definition Energy can be stored Energy can be transferred
Efficiency of energy conversion is:
Solar Energy
Distributed Solar
Photovoltaic Cells: 12-17% efficient
Photovoltaic Cells
Dawn Solar System
Passive Solar
Wind Energy: 30-40% efficient
Small Wind Turbine Systems
Biomass Energy
Wave and Tidal EnergyHydraulic accumulator Wave machineFloat wave power machineDolphin type wave machine
Energy PolicyRenewables Higher capital cost Little or no fuel cost Lower societal andenvironmental costs(externalities) Fossil Fuels Lower capital cost High or variable fuel cost Higher external costs
Overview on fossil fuelThe predicteddemand and supply of crude oil in millions of barrels per day (1 barrel = 159 L) (Evans, 2000)
Fossil fuels are expected to be depleted in 2500
World reserves for gas, oil, and coal will be depleted at 70, 45, and 250 years,respectively.
Alternative Non-fossil Energy Sources1. Nuclear PowerClean and high efficiencyProblems in reprocessing and disposal of spent fuel, the possibility of leak or accidents, and the decommissioning of the power station at the end of their work life.2. Hydroelectric powerClean, non-polluting, long-lasting, renewable sources and no CO2 emission.17% of the electricity supply in developed country and 31% in developing country.Have environmental impacts and can only be sited in certain areas, thus restricting their application.3. Tidal powerClean, non-polluting, long-lasting, renewable sources and no CO2 emission.Limited sites. 10% of the energy for hydroelectricity.4.Wind powerClean, non-polluting, long-lasting, renewable sources and no CO2 emission.Can not control.5. Geothermal power6. Solar energy7. Biological energyBiological materials possible sources of energy, gas, and liquid fuelsHeat from hot springs and molten rock can be used to run steam turbine for electric generation.
Active Learning ApproachIn the traditional approach to higher education, the burden of communicating course material resides primarily with the instructor.In student-centered instruction (SCI), some of this burden is shifted to the students.
Trauma and GriefStudents forced to take major responsibility for their own learning go through some or all of the steps psychologists associate with trauma and grief:
Shock: "I don't believe it - we have to do the reading and she isn't going to lecture on the chapter before the problems are due?" Denial: "She can't be serious about this - if I ignore it, it will go away."Strong emotion: "I can't do it - I'd better drop the course and take it next semester" or "She can't do this to me - I'm going to complain to Dr. M!"Resistance and withdrawal: "I'm not going to play her dumb games - I don't care if she fails me."Surrender and acceptance: "OK, I think it's stupid but I'm stuck with it and I might as well give it a shot."Struggle and exploration: "Everybody else seems to be getting this - maybe I need to try harder or do things differently to get it to work for me."Return of confidence: "Hey, I may be able to pull this off after all - I think it's starting to work."Integration and success. "YES! This stuff is all right - I don't understand why I had so much trouble with it before."