Virginia SOL 6.2

In November of 1965, a power plant stopped working and much of the Northeast was left without electricity for over 13 hours.

30 million people were affected.

How much of your life depends on electricity?

A fuel is a substance that provides a form of energy-such as heat, light, electricity, or motion-- as the result of a chemical change.

If you rode to school in a car or bus today you used a form of energy that comes from a fuel.

The energy from the fuel is released by the process of combustion (burning the fuel).

Energy stored in fuels can be used to generate electricity.

In power plants...1. the thermal energy produced by burning

fuels is used to boil water, making steam. 2. The mechanical energy of the steam turns the

blades of a turbine. 3. The shaft of the turbine is connected to a

generator, which consists of powerful magnets surrounded by coils of copper wire.

4. As the shaft rotates, the magnets turn inside the wire coil, producing an electric current.

5. The electric current flows through power lines to homes and industries.

What are 3 energy conversions that might occur in a power plant?

Most of the energy used today comes from organisms that lived hundreds of millions of years ago.

These plants and animals died. Layers of rock, sand and mud buried the dead organisms. Heat and pressure over time changed them into other substances (fossil fuels).

The three fossil fuels are coal, oil, and natural gas.

All fossil fuels are made up of hydrocarbons which makes them an excellent source of energy (more so than any other fuel).

Why do fossil fuels yield more energy than other fuels?

Coal is a solid fossil fuel formed from plant remains.

Coal was a minor source of energy compared to wood until the 1800's.

When Europe and The U.S. entered the Industrial Revolution, the need for fuel increased rapidly. (more expensive firewood and need for fueling huge steam engines to run trains, ships and factories)

Coal has to be removed from the ground or mined.

Known deposits of coal (and other fossil fuels) that can be removed from the ground using current technology are called reserves.

It is easier to remove coal from the ground now than it was years ago because of machinery, but it is still a dangerous job. (black lung and injuries from mines)

Today, coal provides 23% of the energy used in the United States. Major use= fuel electric power plants.

Advantages:1. Most plentiful in U.S.2. Easy to transport3. Provides a lot of energy when burned

Disadvantages:1. Mining can increase erosion.2. Runoff from mines can cause water pollution. 3. Burning coal results in more air pollution.

Oil (petroleum) is a thick, black, liquid fossil fuel.

It is formed from the remains of small animals, algae, and protists that lived in oceans and shallow inland seas hundreds of millions of years ago.

Most oil deposits are found underground in holes in sandstone or limestone (like water in holes of a sponge).

Petroleum accounts for more than 1/3 of the energy produced in the world.

Fuel for most cars, airplanes, trains and ships comes from it and many homes are heated by oil.

The U.S. consumes about one-third of the oil produced in the world and only 3% of the world's supply is located in the U.S. We must purchase oil from other countries.

Finding oil is difficult. Scientists use sound waves to locate oil

deposits. Only about 1 out of every 6 wells drilled

produces a usable amount of oil.

When oil is first pumped out of the ground it is called crude oil.

It goes under a process called refining in a refinery to be turned into useful products. (gasoline and heating oil)

Many products we use every day are made from crude oil.

Petrochemicals are compounds that are made from oil. (used in plastics, paints, medicines and cosmetics)

How is petroleum used?

Natural Gas is a mixture of methane and other gases.

Formed from the same organisms as petroleum.

Often rises above an oil deposit, forming a pocket of gas in the rock.

Pipelines transport the gas from its source to the places it is used.

It can also be compressed into a liquid and stored in tanks as fuel for trucks and buses.

Advantages:1.Produces large amounts of energy.2.Produces lower levels of air pollution.3.Easy to transport.

Disadvantage: It is highly flammable.

Natural gas has no odor, however, gas companies prevent dangerous explosions from leaks by adding a chemical with a distinct smell to the gas before it is piped to homes and businesses.

Fossil fuels are considered nonrenewable resources because they take hundreds of millions of years to form.

Nonrenewable resources are natural resources that are not replaced as they are used.

Earth's oil reserve took 500 million years to form and ¼ of the oil has already been used up.

Uneven distribution of fossil fuel reserves cause political problems in the world.

How would the world be affected if fossil fuel ran out?

Most Electric power would disappear. Most buildings would lose heating/cooling. Forests would disappear as people

burned wood for heat and cooking. Almost all transportation would stop. Cars, buses, trains, airplanes and ships

would be stranded wherever they ran out of fuel.

Communication would be reduced. (think radios, TV, computers, and telephones)

How can we solve the problem of fossil fuels running out?

1.Find new sources of energy.2.Make the fuels available now last as long as

possible.

Energy conservation= reducing energy use.

Example: walking to the store instead of getting a ride.

We need to use fuels efficiently. Efficiency is the percentage of energy that is actually used to perform work and not “lost” to surroundings as heat.

Example: lights use about 10 percent of the electricity in your home but most is wasted as heat instead of light. (Compact fluorescent light bulbs are better than incandescent light bulbs for this reason)

Insulation helps to increase the efficiency of heating and cooling systems. It is a layer of material that helps block the transfer of heat between the air inside and outside of a building.

1. Fiberglass (looks like fluffy pink cotton)2. Double Window pane (in buildings built

after 1980)

Transporation1.Energy efficient cars and tires2.Public Transit systems3.Carpooling (HOV lanes)

Keep home cooler in winter and warmer in summer.

Use natural lighting whenever possible. Turn off lights and TV when you leave a

room. Walk or ride a bike. Ride buses and trains

for long trips. Recycle, especially metal products such as

aluminum.