Sources of Energy LESSON 1 Energy Use and Renewal Sources of Energy LESSON 1

WHAT ARE RENEWABLE RESOURCES? Natural resources are materials that people take from the Earth. Nature replaces some of those resources relatively easy; some resources can be reused. They are called renewable resources. Example the sun. Nonrenewable resources cannot be replaced or take so long to replace. They include copper, coal, and oil. Some renewable resources can become nonrenewable if they are used at a faster rate than they can be replaced. Example timber, over-fishing the ocean, and hunting wildlife.

WHAT ARE RENEWABLE RESOURCES?

Inexhaustible Resources Resources that are unlimited and cannot be used up by human activity are inexhaustible resources. Example: sunlight, wind, and water. The quality of these resources are affected by human activity. Pollution in the water ways and change in climate patterns can affect the availability of these resources. Most minerals or rocks such as salt, calcite, gold are limited in supply. Therefore, they must be used with care limiting their waste. Quarts is one of the few abundant minerals and is considered inexhaustible.

How do we get energy from fossil fuels? Fossils fuels are a source of energy formed from the remains of plants and animals that lived hundreds of million of years ago. Coal, oil, and natural gas are fossil fuels. Coal is formed in ancient swamps. When plants died, they sank to the bottom where heat and pressure slowly changed the remains into coal. Oil and natural gas formed from the remains of tiny organisms that once lived in the ocean. Heat and pressure slowly changed their remains into natural resources.

BURNING FOSSIL FUELS When burning fossil fuels, the chemical energy in the fuel is converted to thermal energy. That’s what makes it a useful resource. Natural gas is used for cooking and heating homes. Almost all transportation in the United States run on fossil fuels. Most electric energy is generated by burning fossil fuels.

Burning Fossil Fuels

Fossil Fuels are limited The United States uses coal to supply a large portion of their energy needs. There are large deposits of coal along the Appalachian Mountains and in many western states. Oil is primarily used as fuel for transportation. It is also used to make materials such as plastics. Fossil fuels are considered nonrenewable because it takes great amount of time to produce. With the growth of industry, the demand for energy has grown faster than we can renew our resources.

Fossil Fuels are limited

WHAT ARE ALTERNATIVE ENERGY RESOURCES? Alternative energy resources are any form of energy produced from other than fossil fuels. These include energy from atoms, heat from inside the Earth, the Sun, moving water, and wind. The energy that is released from the breakup of atoms is called nuclear energy. Nuclear power plants produce electricity by splitting uranium atoms inside a structure called a reactor.

RENEWABLE ENERGY

Nuclear Energy

SOLAR ENERGY The Sun provides an inexhaustible supply of light energy and thermal energy. Energy from the sun is called solar energy. Sunlight is converted directly to electrical energy in a device called photovoltaic cell. Sunlight strikes a doped semiconductor. The knock of sunlight releases electrons in the doped semiconductor out of position, giving them the energy to move. Solar panels have a top layer of glass that protects the parts inside the panel. Inside the panel there is an antireflective layer that allows the panel to absorb sunlight.

SOLAR ENERGY

WHAT IS GEOTHERMAL ENERGY? The thermal energy from inside the Earth is called geothermal energy. It can be used to heat homes and generate electricity in power plants. Places where magma is close to the surface, ground water gets extremely hot. This deep hot groundwater is called geothermal reservoir. Hot springs and geysers form where geothermal reservoirs are found. Geothermal reservoirs close to the ground are drilled and the water is pumped to use as an energy source.

WHAT IS GEOTHERMAL ENERGY?

HOW IS WATER USED TO GENENRATE ELECTRICITY? Electricity generated by flowing water is called hydroelectricity. Today this is generated by hydroelectric dams. The water behind the dams form a reservoir. Using the force of gravity, the water flows downwards in a built-in tunnel. At the bottom, the flowing water is collected and spun by a turbine. A generator turns the collected energy to electric energy ready to be used to heat homes.

HOW IS WATER USED TO GENENRATE ELECTRICITY?

HOW CAN WE GET ENERGY FROM THE WIND? The atmosphere’s moving air, or wind, is another inexhaustible supply of energy. Just as blowing on a pinwheel’s blades make them spin, wind moves the blades of a windmill. Wind turbines work on the same basic principle as a power plant. These turbines convert energy into electricity. A group of turbines can produce electricity on a large scale and are called wind farms.

HOW CAN WE GET ENERGY FROM THE WIND?

CLASSWORK COMPLETE LESSON 1 REVIEW PAGE 375 WRITE DEFINITIONS FOR LESSON 1, Unit 7- Page 364 PROJECT: page 363 to be done in class on Tuesday, March 27- Wednesday, March 28.

HOMEWORK Choose two types of energy plants discussed in this lesson and make a poster that explains how they work. Collect items to complete the launch lab on page 363.