Introduction
Would you believe that 18 percent of the world’s population uses 56 percent of the world’s energy supply? Would you believe that the United States consumes almost 25 percent of the world’s energy, but has only 3 percent of the world’s population? All of the resources that we use every day to meet our needs and wants are provided through the use of natural resources.
Natural resources are either renewable or nonrenewable. Renewable resources are materials that can be replaced through natural and/or human processes.
Exhaustible resources exist in fixed amounts within the earth. Once they’re used up, they are gone forever. Inexhaustible resources, like the sun and wind, cannot be used up.
Energy derived from natural resources, lights, heats, and cools our homes, schools, and factories. It powers the machines of industry and transportation. The clothing we wear, the food we eat, the buildings in which we live, and even the systems we use to communicate are all dependent on energy. For generations, our society has been enjoying the benefits of plentiful, inexpensive, and easily available energy–fossil fuels. But these fuels, such as coal, oil, and natural gas, are finite. As supplies have decreased and become more expensive to extract, the search has intensified for alternative energy sources–sources of energy other than fossil fuels.
The most obvious and virtually limitless energy source is the sun. In terms of humankind’s residence on Earth, the sun will last forever, continuously radiating energy that makes life on our planet possible. Although Earth intercepts only a small fraction of the total energy emitted by the sun, the amount received is thousands of times the present energy requirement of the world’s human population.
Human activities over the past one hundred years, particularly fossil fuel burning and deforestation, are releasing unnatural amounts of carbon dioxide (CO2) into the atmosphere. Today people are concerned about the rising CO2 concentration in the atmosphere due to the dangers of climate change. Many engineers are working to reduce CO2 emissions. For example, environmental engineers are studying carbon sequestration—a term used to describe processes that remove carbon from the atmosphere. Mechanical and electrical engineers are working to design buildings, homes, cars, and appliances that use less energy. They are also engineering devices like solar panels and wind turbines that generate electricity from natural sources and do not emit CO2 into the atmosphere.
The average American home spends about $1,000 on electricity alone every year. The average electricity cost in the United States is about 12 cents per kilowatt-hour (kWh), so using 1000 watts of electricity for an hour costs 12 cents. Energy you save in your home means no energy was lost producing it or transporting it to your home. In this activity you will explore ways that you can use energy sources more efficient
Task
Compare the electric bills for two residents that live next door to each other in apartments that are identical in size and style.
Figure 1. Electric Bill for A. Citizen
Figure 2. Electrical Bill for B. Citizen
Process
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Explore the cost of electrical device use at the Energy Resource Center webpage.
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Investigate the Energy Sources Recent Statistics webpage. (click this link)
Evaluation
1. Whose apartment uses less energy, A. Citizen or B. Citizen?
2. If both apartments are identical in size and style, why might one of the electric bills be higher?
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Reflection Question:
3. Which electrical devices use the most energy and cost the most to operate?
4. Which are the least?
Compare the electrical use habits of A. Citizen and B. Citizen using the table below:
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5. Explain the factors that contribute to one of the homes using less energy than the other home.
6. What factors contribute to B. Citizen consuming more electricity than A. Citizen? -
7. How can B. Citizen reduce the price of their electric bill?
Conclusion
8. Write a question about energy consumption in the United States (or your state or local community) that you are interested in answering.
Teacher Page
Would you believe that 18 percent of the world’s population uses 56 percent of the world’s energy supply? Would you believe that the United States consumes almost 25 percent of the world’s energy, but has only 3 percent of the world’s population? All of the resources that we use every day to meet our needs and wants are provided through the use of natural resources.
Natural resources are either renewable or nonrenewable. Renewable resources are materials that can be replaced through natural and/or human processes.
Exhaustible resources exist in fixed amounts within the earth. Once they’re used up, they are gone forever. Inexhaustible resources, like the sun and wind, cannot be used up.
Energy derived from natural resources, lights, heats, and cools our homes, schools, and factories. It powers the machines of industry and transportation. The clothing we wear, the food we eat, the buildings in which we live, and even the systems we use to communicate are all dependent on energy. For generations, our society has been enjoying the benefits of plentiful, inexpensive, and easily available energy–fossil fuels. But these fuels, such as coal, oil, and natural gas, are finite. As supplies have decreased and become more expensive to extract, the search has intensified for alternative energy sources–sources of energy other than fossil fuels.
The most obvious and virtually limitless energy source is the sun. In terms of humankind’s residence on Earth, the sun will last forever, continuously radiating energy that makes life on our planet possible. Although Earth intercepts only a small fraction of the total energy emitted by the sun, the amount received is thousands of times the present energy requirement of the world’s human population.
Human activities over the past one hundred years, particularly fossil fuel burning and deforestation, are releasing unnatural amounts of carbon dioxide (CO2) into the atmosphere. Today people are concerned about the rising CO2 concentration in the atmosphere due to the dangers of climate change. Many engineers are working to reduce CO2 emissions. For example, environmental engineers are studying carbon sequestration—a term used to describe processes that remove carbon from the atmosphere. Mechanical and electrical engineers are working to design buildings, homes, cars, and appliances that use less energy. They are also engineering devices like solar panels and wind turbines that generate electricity from natural sources and do not emit CO2 into the atmosphere.
The average American home spends about $1,000 on electricity alone every year. The average electricity cost in the United States is about 12 cents per kilowatt-hour (kWh), so using 1000 watts of electricity for an hour costs 12 cents. Energy you save in your home means no energy was lost producing it or transporting it to your home. In this activity you will explore ways that you can use energy sources more efficiently.