energy resources

energy use and conservation

Figure 17.22 shows the mix of energy resources used worldwide in 2006. Fossil fuels still provide most of the worlds energy, with oil being the single most commonly used energy resource. Natural gas is used less than the other two fossil fuels, but even natural gas is used more than all renewable energy resources combined. Wind, solar, and geothermal energy contribute the least to global energy use, despite the fact that they are virtually limitless in supply and nonpolluting.

energy use by nation

People in the richer nations of the world use far more energy, especially energy from fossil fuels, than people in the poorer nations do. Figure 17.23 compares the amounts of oil used by the top ten oil-consuming nations. The U.S. uses more oil than several other top-ten countries combined. If you also consider the population size in these countries, the differences are even more stunning. The average person in the U.S. uses a whopping 23 barrels of oil a year! In comparison, the average person in India or China uses just 1 or 2 barrels a year. Because richer nations use more fossil fuels, they also cause more air pollution and global warming than poorer nations do.

fossil fuels

Fossil fuels are mixtures of hydrocarbons that formed over millions of years from the remains of dead organisms. They include petroleum (commonly called oil), natural gas, and coal. Fossil fuels provide most of the energy used in the world today. They are burned in power plants to produce electrical energy, and they also fuel cars, heat homes, and supply energy for many other purposes. You can see examples of their use in Figure 17.19. Fossil fuels contain stored chemical energy that came originally from the sun. Ancient plants changed energy in

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nonrenewable energy resources

Nonrenewable resources are natural resources that are limited in supply and cannot be replaced except over millions of years. Nonrenewable energy resources include fossil fuels and radioactive elements such as uranium.

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renewable energy resources

Renewable resources are natural resources that can be replaced in a relatively short period of time or are virtually limitless in supply. Renewable energy resources include sunlight, moving water, wind, biomass, and geothermal energy. Each of these energy resources is described in Table 17.1. Resources such as sunlight and wind are limitless in supply, so they will never run out. Besides their availability, renewable energy resources also have the advantage of producing little if any pollution and not contributing to global warming. The technology needed to gather energy from renewable resources is currently expensive to install, but most of the resources themselves are free for the taking. here? Renewable Energy Resource Sunlight The energy in sunlight, or solar energy, can be used to heat homes. It can also be used to produce electricity in solar cells. However, solar energy may not be practical in areas that are often cloudy. Example Solar panels on the roof of this house generate enough electricity to supply a familys needs. Moving Water When water falls downhill, its potential energy is con- verted to kinetic energy that can turn a turbine and generate electricity. The water may fall naturally over a waterfall or flow through a dam. A drawback of dams is that they flood land upstream and reduce water flow downstream. Either effect may harm ecosystems. Wind Wind is moving air, so it has kinetic energy that can do work. Remember the wind turbines that opened this chapter? Wind turbines change the kinetic energy of the wind to electrical energy. Only certain areas of the world get enough steady wind to produce much electricity. Many people also think that wind turbines are noisy and unattractive in the landscape. Water flowing through Hoover dam between Arizona and Nevada generates electricity for both of these states and also by southern California. The dam spans the Colorado River. This old-fashioned windmill captures wind energy that is used for pumping water out of a well. Windmills like this one have been used for centuries. Renewable Energy Resource Biomass The stored chemical energy of trees and other plants is called biomass energy. When plant materials are burned, they produce thermal energy that can be used for heating, cooking, or generating electricity. Biomassespecially woodis an important energy source in countries where most people cant afford fossil fuels. Some plants can also be used to make ethanol, a fuel that is added to gasoline. Ethanol produces less pollution than gasoline, but large areas of land are needed to grow the plants needed to make it. Geothermal Heat below Earths surfacecalled geothermal en- ergycan be used to produce electricity. A power plant pumps water underground where it is heated. Then it pumps the water back to the plant and uses its thermal energy to generate electricity. On a small scale, geothermal energy can be used to heat homes. Installing a geothermal system can be very costly, how- ever, because of the need to drill through underground rocks. Example This large machine is harvesting and grinding plants to be used for biomass energy. This geothermal power plant is located in Italy where hot magma is close to the surface.

kqed big solar comes of age

The largest solar thermal plant in the world opens in Californias Mojave Desert, after a debate that pitted renewable energy against a threatened tortoise. The Ivanpah solar plant is one of seven big solar farms scheduled to open in California in the coming months, as a result of the states push to produce one third of its electricity from renewable energy. Some 30 states have similar mandates. For more information on this solar plant, see http://science.kqed.org/ MEDIA Click image to the left or use the URL below. URL:

nuclear energy

Like fossil fuels, the radioactive element uranium can be used to generate electrical energy in power plants. In a nuclear power plant, the nuclei of uranium atoms are split in the process of nuclear fission. This process releases a tremendous amount of energy from just a small amount of uranium. The total supply of uranium in the world is quite limited, however, and cannot be replaced once it is used up. This makes nuclear energy a nonrenewable resource. Although using nuclear energy does not release carbon dioxide or cause air pollution, it does produce dangerous radioactive wastes. Accidents at nuclear power plants also have the potential to release large amounts of radioactive material into the environment. Figure 17.21 describes the nuclear disaster caused by a Japanese tsunami in 2011. You can learn more about the disaster and its aftermath at the URLs below.

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kqed whats next for nuclear

President Obama says the United States needs new nuclear reactors, to meet the countrys energy demands and counter climate change. But can nuclear power be produced more safely and affordably? A scientist at the University of California, Berkeley, is working to do just that. For more information about nuclear energy, see http://science.k MEDIA Click image to the left or use the URL below. URL:

kqed airborne wind energy

On the windswept tarmac of the former Alameda Naval Air Station, an inventive group of scientists and engineers are test-flying a kite-like tethered wing that may someday help revolutionize clean energy. QUEST explores the potential of wind energy and new airborne wind turbines designed to harness the stronger and more consistent winds found at higher altitudes. For more information on wind energy, see http://science.kqed.org/quest/video/airborne MEDIA Click image to the left or use the URL below. URL:

conserving energy

We can reduce our use of energy resources and the pollution they cause by conserving energy. Conservation means saving resources by using them more efficiently or not using them at all. Figure 17.24 shows several ways that people can conserve energy in their daily lives. You can find more energy-saving tips at the URL below. What do you do to save energy? What else could you do?

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kqed web extra home energy audit

QUEST teams up with Climate Watch to give you an inside look at home energy efficiency. Tag along with Sustainable Spaces on a home efficiency "green-up" and learn tips on how to make your home more energy efficient. For more information on home energy audits, see http://science.kqed.org/quest/video/web-extra-home-energy-audit/ . MEDIA Click image to the left or use the URL below. URL:

kqed geothermal heats up

Solar and wind power may get the headlines when it comes to renewable energy. But another type of clean power is heating up in the hills just north of Sonoma wine country. Geothermal power uses heat from deep inside the Earth to generate electricity. The Geysers, the worlds largest power-producing geothermal field, has been providing electricity for roughly 850,000 Northern California households, and is set to expand even further. For more information on geothermal energy, see http://science.kqed.org/quest/video/geothermal-heats-up/ . MEDIA Click image to the left or use the URL below. URL:

kqed climate watch unlocking the grid

With the race on to reduce global warming and fossil fuel dependency, experts in alternative energy see a bright future for renewable resources like wind, solar, hydro-power and geothermal energy. QUEST and Climate Watch team up to look at the "Smart Grid" of the future and how it might be improved to more cleanly and efficiently keep the lights on in California. For more information on the "Smart Grid", see http://science.kqed.org/quest/video/clim MEDIA Click image to the left or use the URL below. URL:

instructional diagrams

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questions

Nonrenewable energy resources include

a. fossil fuels.

b. running water.

c. radioactive elements.

-->  d. two of the above

All of the following energy resources are fossil fuels except

a. oil.

b. coal.

-->  c. biomass.

d. natural gas.

Natural gas is used for energy in

a. motor vehicles.

b. water heaters.

c. furnaces.

-->  d. all of the above

Petroleum is used to make

a. heating oil.

b. kerosene.

c. gasoline.

-->  d. all of the above

All fossil fuels contain stored chemical energy that came originally from

a. rocks below Earths surface.

b. marine organisms.

c. giant tree ferns.

-->  d. the sun.

Which statement about uranium is true?

a. It is nearly limitless in supply.

b. It is a renewable energy resource.

-->  c. It is not as safe to use as solar energy.

d. Using it for energy creates air pollution.

What is the function of a wind turbine?

-->  a. changing the kinetic energy of wind to electrical energy

b. capturing wind energy and using it to pump water

c. slowing down the wind so it causes less erosion

d. storing the energy of wind as thermal energy

The fossil fuel that produces the most carbon dioxide when burned is

a. oil.

-->  b. coal.

c. biomass.

d. natural gas.

A major drawback of nuclear energy is the production of

a. air pollution.

b. carbon dioxide.

c. carbon monoxide.

-->  d. radioactive wastes.

Geothermal energy

-->  a. comes from heat below Earths surface.

b. cannot be used to produce electricity.

c. is only used to heat homes.

d. is nonrenewable.

Renewable energy resources include

a. wind.

b. biomass.

c. moving water.

-->  d. all of the above

Solar cells convert solar energy to

a. heat.

b. steam.

c. thermal energy.

-->  d. electrical energy.

All natural resources need to be conserved so they are not used up.

a. true

-->  b. false

Most of the electricity in the U.S. is generated by burning petroleum.

a. true

-->  b. false

The use of fossil fuels is a major cause of global warming.

-->  a. true

b. false

Nuclear energy is a renewable energy resource.

a. true

-->  b. false

Natural gas formed when the remains of swamp plants were pressed beneath layers of sediments.

a. true

-->  b. false

It takes millions of years for fossil fuels to form.

-->  a. true

b. false

Most of the electric power in the U.S. is generated from running water.

a. true

-->  b. false

The burning of fossil fuels leads to the formation of acid rain.

-->  a. true

b. false

It takes a large amount of uranium to produce a small amount of nuclear energy.

a. true

-->  b. false

Renewable energy resources produce air pollution.

a. true

-->  b. false

Fossil fuels provide most of the worlds energy.

-->  a. true

b. false

Coal and petroleum are often found together.

a. true

-->  b. false

Smog comes from the burning of fossil fuels.

-->  a. true

b. false

Using moving water to generate electricity never harms the environment.

a. true

-->  b. false

Wind turbines change the kinetic energy of wind to electrical energy.

-->  a. true

b. false

saving resources by using them more efficiently

-->  a. conservation

b. natural resource

c. fossil fuel

d. biomass energy

e. renewable resource

f. geothermal energy

g. nonrenewable resource

resource that is limited in supply and cannot be replaced

a. conservation

b. natural resource

c. fossil fuel

d. biomass energy

e. renewable resource

f. geothermal energy

-->  g. nonrenewable resource

energy from plant materials

a. conservation

b. natural resource

c. fossil fuel

-->  d. biomass energy

e. renewable resource

f. geothermal energy

g. nonrenewable resource

mixture of hydrocarbons that formed from the remains of dead organisms

a. conservation

b. natural resource

-->  c. fossil fuel

d. biomass energy

e. renewable resource

f. geothermal energy

g. nonrenewable resource

heat from below Earths surface that can be used for energy

a. conservation

b. natural resource

c. fossil fuel

d. biomass energy

e. renewable resource

-->  f. geothermal energy

g. nonrenewable resource

anything people use that comes from nature

a. conservation

-->  b. natural resource

c. fossil fuel

d. biomass energy

e. renewable resource

f. geothermal energy

g. nonrenewable resource

resource that is virtually limitless in supply or can be replaced quickly

a. conservation

b. natural resource

c. fossil fuel

d. biomass energy

-->  e. renewable resource

f. geothermal energy

g. nonrenewable resource

diagram questions

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