Key TermsKey TermsUse the spaces below to define the key terms in your own words.Use the spaces below to define the key terms in your own words.

4.1Key Terms Textbook Definition Drawing / In my own words

Fossil fuels

Nuclear fission

Geothermal energy

biomass

cogeneration

Fuel cells

Non-renewable resource

Renewable resource

4.2Key Terms Textbook Definition Drawing / In my own words

Fly ash

4.3Key Terms Textbook Definition Drawing / In my own words

Binary numbers

CCHAPTERHAPTER 4 – T 4 – THEHE U USESE OFOF E ELECTRICALLECTRICAL E ENERGYNERGY A AFFECTSFFECTS S SOCIETYOCIETY ANDAND THETHE E ENVIRONMENTNVIRONMENT

4.1 – E4.1 – ELECTRICALLECTRICAL E ENERGYNERGY S SOURCESOURCES ANDAND A ALTERNATIVESLTERNATIVES

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Around the world, about 65% of all electric power is generated by burning _____, _______, or _______ ________. These fuels are called fossil fuels because they are formed from the __________________ of plants and animals.

Using Heat to generate electricity

Coal can be used to turn a ________________. First, the coal is powdered, then blown into a combustion chamber and burned to release _______. The heat boils water and creates ________ under high pressure and temperature. The high pressure steam drives a large turbine. The turbine shaft rotates large electromagnetic coils in the generator to produce __________________. Oil or natural gas can also be burned instead of coal in the combustion chamber.

http://www.youtube.com/watch?v=SeXG8K5_UvU

Nuclear reactors can also be used as a way to provide heat for a steam operated generator. In nuclear reactors, heavy elements such as _______________ are split in chain reactions known as nuclear fission, which results in large amounts of ______________ being released

http://www.youtube.com/watch?v=cXvc5jQVkVI

The Earth’s core also provides a lot of heat that can be used to generate electricity. The heat from the Earth’s core causes the water to heat up and be released as ___________. This energy is referred to as ____________________________ which can be harvested to drive turbines.

http://www.youtube.com/watch?v=-ajqiPe_9Ko

_________________can also be used as a heat source. Most accurately describes as garbage, it consists of ____________________ garbage and the gases it releases as

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well as yard clippings, dead trees, unused crops, and food-based garbage, all of which can be burned to produce steam.

____________________________ is also another process which uses the waste energy from a process for another purpose, such as heating or generating electricity. For example: glass manufacturing, the waste heat produced from the manufacturing process can be used to produce steam.

Using Water Power to Generate Electricity

About 20% of the world’s electricity is generated by hydro-electric power plants. This process captures the energy from falling water. Some plants like Niagra Falls use the flow from the waterfall, but most use a dam across a river to store water in a reservoir. Water is directed through a channel called a penstock to a large paddle-covered turbine. The rushing water spins the turbine, which is connected to a generator in the same way as a steam-driven turbine.

http://www.youtube.com/watch?v=rnPEtwQtmGQ

Alternative Energy Sources

There are four types of alternative energy sources

1. ______________2. ______________3. ______________4. ______________

Moving water from tides can also provide ___________ to turbines to run generators. When the tide comes in, the water is trapped in a reservoir and then let our past the turbines. There are not many tidal stations in the world because of difficulty of finding appropriate locations

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_________ energy can be harnessed to turn a shaft. The amount of electricity that a single windmill can produce is __________, but a number of wind-powered generators can be connected together in ______________________ to produce larger amounts of __________________ energy.

Scientists began using silicon based solar cells are very efficient at producing current. It is common to find solar modules and arrays connected together to power everything from calculators to spacecraft.

Batteries are convenient source of electricity for portable devices. However, large banks of batteries are rarely used because they are _________________________________. Rechargeable batteries are used to provide backup power for emergency lights and computer systems. However, these batteries produce electricity only after being charged by using electricity from an _________________ source. Rechargeable batteries are ____________ 100% efficient; therefore they actually use more electricity than the produce. New research is in developing fuel cells which generate electricity directly from a chemical reaction with a fuel such as hydrogen. More fuel is added as electricity is produced so the cell is no used up as an ordinary cell would be.

Renewable and Non-renewable Energy

Alberta is known for its coal reserves and has enough to last the next 200 years at current consumption rates. However, coal is non-renewable resource – it cannot be replaced as it is used up. Crude oil and natural gas, also found in Alberta will all eventually run out.

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In contrast, ___________________________ can be renewed or replenished in relatively short periods of time. Some are continually replenished. Wind energy, tidal energy, solar energy, geothermal energy, and biomass are resources that naturally renew themselves. If tree harvesting is managed carefully, replanting can ensure that wood supplies for energy can last indefinitely. However, if wood is used faster than the trees can be grown, then the renewable resource cannot meet energy needs indefinitely.

http://www.youtube.com/watch?v=pBTnVoEIb98

Check and Reflect p.350

1. Describe the turbine’s role in an electric generator

3. What is the difference between a renewable and a non-renewable resource?

4. Look at figure 4.6 on page 347. Describe how a solar cell produces electricity

5. What is cogeneration? Give one example.

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6. How can a river be used to produce electricity?

7. What do nuclear power plants and coal-fired plants have in common?

8. Make a chart summarizing how tides, geothermal sources, sunlight, and wind can be used to produce energy?

9. Why don’t power stations use batteries to generate electricity?

4.2 – E4.2 – ELECTRICITYLECTRICITY ANDAND THETHE E ENVIRONMENTNVIRONMENT

Air Pollution

The burning of fossil fuels results in the_______________ of many problem-causing substances into the atmosphere. For example, when coal is burned, it leaves behind a powdery _____. Some of this ash is carried up the smokestack and released into the atmosphere which is referred to as ________. This is a concern because the ash contains small amounts of ________________, which is poisonous and can damage the nervous system. Other pollutants that are released include: ______________, ____________________, and _______________________. Many which result in

_______________ and ___________________ global warming.

Other Environmental Effects

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Most coal comes from __________________. This process is used when deposits are near the surface. This type of mining removes all plants and animals from large areas of land. Although the land can be reclaimed by replacing the soil, the original natural environment is not usually restored 100%.

Oil and gas wells can also affect the surrounding areas; some of these deposits contain _____________________________ which if not handled properly, can be released into the environment. These concentrations are measured for human safety.

In electricity generation, steam turbines often _______________a great deal of warm water into nearby lakes and streams which ____________________ the water temperature and alters the fresh water ecology and sometimes kill fish. Power generation from nuclear reactors create ____________________________ that remain dangerous for thousands of years, Hydro-electric dams

produce no pollutants, but their dams flood many hectares of land and __________ the ecosystems of rivers.

Wind farms and solar cell arrays also require large tracts of land to generate practical amounts of energy. Tidal or wave generators may disrupt ocean habitats. However, the ____________ sources of energy – especially wind, tide, and geothermal – harm the environment much less than fossil fuels do.

Conserving Energy and Non-Renewable Resources

Reserves of oil and gas are decreasing, but it is likely that they will last your lifetime. So why bother conserving energy? If demand for energy _____________________, there is a ________________ demand for the resources that fuel electrical generating plants. The plants would then be able to ____________________ their production or cease to operate, which leads to _______ pollution. When your actions lead to a lower demand on natural resources, you are practicing ____________ ______________________.

The electric car – if you want to conserve fossil fuels you might consider buying an electric car to reduce pollution. Electric cars ___________ the need for gasoline, which comes from oil. Burning less gasoline conserves oil reserves and reduces pollution.

The electric car, however, must get electricity from somewhere for its rechargeable batteries. If a ______ _______ plant supplies this electricity, you may not be saving fossil fuels or reducing pollution. However, if a hydroelectric

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plant, or windmill farm provides this power, fossil fuels will be conserved and pollution will decrease. Both personal and societal decisions must be taken into account when considering conservation.

A Sustainable Future

Conserving energy means moving toward sustainability. Sustainability means using resources at a rate that can be maintained indefinitely. If we do not achieve sustainability, future generations may not be able to support themselves. We may never be able to achieve complete sustainability, but the decisions we make personally and as a society can move us closer to this goal. An example of personal decision would be choosing public transit rather than driving your car. An example of a societal decision is the use of low wattage street lights.

Check and Reflect p. 353

1. How can oil wells affect the environment?

2. Do nuclear power plants produce by-products? If so, are they harmful?

3. What is fly ash? Why is an environmental concern?

4. Explain why you agree or disagree with the following statement. “Green” sources of energy such as solar and wind power have no environmental impact.

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5. What is the difference between energy conservation and energy sustainability?

7. Explain how each of the following actions affect energy sustainability:a. Replacing a coal-fired power plant with several fields of solar arrays

b. Choosing a new refrigerator that is high efficiency

c. Carpooling with friends to drive to work

d. Replacing the incandescent bulbs in your home with compact fluorescent bulbs

8. A friend brags to you about her new electric car that uses rechargeable batteries as an energy source. She says, “My new car doesn’t have an internal combustion engine, so no fossil fuels are needed to provide energy for it.” Is this an accurate statement? Explain your answer.

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4.3 – E4.3 – ELECTRICALLECTRICAL T TECHNOLOGYECHNOLOGY ANDAND S SOCIETYOCIETY

Benefits of Electrical Technologies

Many electrical devices and inventions came out of a desire for ___________ or________________. For example, doing laundry. Before the invention of the washing machine, it could take a whole day to complete the washing. Now, machines do the washing, rinsing, and drying, freeing up people to do other things. Electronic devices also make completing a variety of tasks more ____________and ____________________, and give us more ________ for other activities.

Drawbacks of Electrical Technologies

More technology means that ____________________________ are needed to manufacture and operate devices. They can also make ____________________ more difficult to achieve. As technology advances making other devices obsolete, this creates the problem of ________________________. Some technologies are also very expensive for some countries to adopt which excludes them from the benefits of technological advancement

Check and Reflect p.358

1. Name two benefits of electrical technologies

2. Why could more technology make sustainability more difficult?

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Section Review p 359.

1. What is sustainability? Give one example?

2. Describe the advantages and disadvantaged of using coal as an energy source

3. Briefly describe geothermal and tidal methods of generating electricity

4. Why are coal, natural gas, and oil referred to as “fossil” fuels?

6. A group of Alberta farmers forms a co-operative group and builds a factory that turns grain into alcohol as a field for generators and cars. Would this energy source be renewable or non-renewable? Explain.

7. You notice your neighbour replacing her exterior house lights with lower watt bulbs. Would you describe this as “conservation” or “sustainability”

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