By some projections world reserves of fossil fuels will run out within the century
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. Additionally, global temperatures continue to be affected by the combustion of fossil fuels and the subsequent release of carbon dioxide. Consequently, technologies that efficiently harness the power of renewable resources are in great demand. To be active citizens and innovators it is important for students to be knowledgeable about these issues, the current technologies in use and how they work, and for them to forge potential solutions.
The environmental impact of fossil fuels and the various renewable energies used to reduce that environmental impact comprises a significant portion of the new Phychem curriculum in New Haven. Phychem is a course for 9
th
grade students, which was originally designed to include the fundamentals of chemistry and physics, but has since evolved into a course heavy in environmental science. Additionally the basics of electrical circuitry is included in the curriculum. I, therefore, believe it would be a comprehensive end-of-the-year unit to have students design their own model “power plants,” fueled by some form of renewable resource. The plant should run a generator to produce electricity to light a string of light emitting diodes (LEDs). The necessary foundational knowledge will be covered before students begin their projects.
This unit will be designed for a 9th grade, high school Phychem class in New Haven, CT. According to Census.gov
, New Haven’s per capita income is about 80% of the national average and its median household income is only about 69% of the national median
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. Many of the students I teach come from a low-income households, which means saving on their energy bill could be very important to them. New Haven has many old homes that can be drafty, leading to high heat and electric bills (assuming the use of electric heaters). Additionally, the oil refineries located in New Haven contribute to poor air quality. According to the U.S. Energy Information Agency, electricity prices in Connecticut are about 68% higher than the national average at 17.24 cents per kilowatt hour (kWh). Consequently, acquiring cheap, clean forms of alternative energy is especially important to my students. Effort will be made during the unit to make these connections apparent between the material, economics and their community.
Unit Description
In preparation for their project of building model power plants, students will need to master certain content. Students will learn about fossil fuels and their environmental impact. They will learn the basic process for how most power plants function, that is, by spinning a turbine to power a generator. They will be introduced to a variety of existing alternative and renewable energies as well as some ideas on the fringe of our scientific capabilities. Students must understand the basics of circuitry including Ohm’s law. They will be able to define combustion and consider some of its effects based on balanced stoichiometry. Perhaps most importantly, students will quantitatively analyze the advantages, disadvantages, and life cycle of these many technologies.
Students will be tasked with designing their own method of generating electricity using renewable resources. They may choose a renewable resource already used to produce electricity such as wind or solar, or they may attempt this goal using a novel strategy. Students will need to first present their preliminary ideas to receive teacher approval. They will then need to submit designs for their model to be approved by their teacher and finally a working model of their electricity producing systems.
Students will be given the basic circuitry components and directions to wire from the generator to the LEDs. Students will use the knowledge they accumulated throughout the year in Phychem to make their own designs on how they will power their generator to accomplish to goal of powering the LEDs. This goal must be accomplished with a renewable resource of any kind. Students may choose to not use the generator if they use a renewable resource that does not require it, such as solar. A list of materials needed will be submitted with the model designs and will be approved based on whether such materials are readily available.
When society first started using fossil fuels for energy, heat, and transportation needs we failed to foresee some of the consequences. Future impact is something engineers must take more seriously if we are to avoid some of our old mistakes. Part of their assignment will be to quantitatively demonstrate that their technology will improve upon fossil fuels in terms of environmental impact. Students must conduct in-depth research on their technology, including what sort of resources and energy go into building their technology to assess the environmental impact to get it off the ground. Calculations will be provided with work, showing the amount of carbon dioxide (CO
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) or other environmental hazards produced in the manufacturing and implementation of their technology; CO
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released from the production or solar cells or their distribution for instance; the ratio of CO
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produced to power output for comparison with fossil fuel sources. Students will be required to graph CO
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(or other environmental pollutant) production over time for their technology to show how long it will take to result in a positive environmental impact in comparison to a traditional coal power plant for instance. Students will also be tasked with considering the scale-ability of their technology. Is their technology something that could replace a large coal power plant or is it something that may only be useful for small or residential applications; solar windows for example.
This project will be scaffolded throughout the quarter as to guide students through the various steps. They will be graded significantly on their ability to quantitatively demonstrate that their technology works efficiently, is useful and will positively impact the environment over fossil fuels. Their ability to provide evidence using mathematics that their technology’s power to CO
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emission ratio is superior to coal, oil and natural gas is central to their project’s successful completion. These mathematics will also be scaffolded and investigated over several class periods. Teacher checks will be included regularly throughout the unit to ensure student’s projects meet the requirements and students are on pace. Students will compile this information in a three page summary paper along with their final model, summarizing their projects, the research they conducted, what challenges they faced and how their technology will improve human environmental impact and lead to a healthier world.
