Chapter 12: Conserving Resources SPI 0707.7.7

Ch. 12 Section 1 Learning Objectives Compare renewable resources and nonrenewable resources List uses of fossil fuels Identify alternatives to fossil fuel use Main idea: Earth has natural resources that can be replenished as well as natural resources that cannot be replenished.

New Vocabulary Natural resource Renewable resource Nonrenewable resource Petroleum Fossil fuel Hydroelectric power Nuclear energy Geothermal energy

Natural Resources Natural resources are those parts of the environment that are useful or necessary for the survival of living organisms. What kind of natural resources do you use? Food, air, water? Natural resources also supply energy for automobiles & power plants Some resources are plentiful and some are not

Renewable Resources A renewable resource is any natural resource that is recycled or replaced constantly by nature. The sun supplies a constant supply of heat & light Rain fills lakes and streams with water Plants carry out photosynthesis and put oxygen back into the air

Renewable Resources Renewable resources can be recycled or replaced, but they are in short supply (sometimes) Rain may not refill lakes, rivers, or streams and water may become short in supply In desert regions water and other resources are scarce

Nonrenewable Resources Natural resources that are used up more quickly than they can be replaced by natural processes are nonrenewable resources. Earth’s supply of these is limited Plastics, paints, and gasoline are made from an important nonrenewable resource called petroleum formed mostly from remains of microscopic marine organisms buried in Earth’s crust. It takes hundreds of millions of years to form

Nonrenewable Resources Minerals and metals found in Earth’s crust are also nonrenewable What are some nonrenewable resources you can think of? Petroleum, diamond, graphite, iron, copper, tin, gold, silver, tungsten, uranium Many, many manufactured items are made from nonrenewable resources (cars, homes, etc…)

Fossil Fuels Coal, oil, and natural gas are some nonrenewable resources that supply energy. Fossil fuels are fuels formed in Earth’s crust over hundreds of millions of years All types of transportation that use gasoline, diesel fuel, and jet fuel use oil Coal is used in power plants to produce electricity Natural gas is used in manufacturing for heating, cooking, and sometimes fuel

Problems with Fossil Fuels We all use fossil fuels everyday Earth’s supply of fossil fuels is limited They may become expensive and difficult to obtain in the future Using fossil fuels may cause environmental problems Mining coal strips away thick layers of soil and rock which destroys ecosystems Burning fossil fuels produces waste gases that cause pollution

Conserving Fossil Fuels How can we conserve fossil fuels? Turn lights, appliances, etc off when not using Reduces electricity, which is produced in power plants that fossil fuels Taking public transportation or riding in car pools reduces exaust Walking or riding bicycles

Alternatives to Fossil Fuels Developing alternative uses to fossil fuels is also a way to conserve Using water, wind, and solar or atomic energy is an alternative Wind and solar energy are so plentiful that they are considered inexhaustible resources

Alternatives to Fossil Fuels Water Wind Solar Nuclear Geothermal

Water Power Water is a renewable energy source that can be used to generate electricity Hydroelectric power is electricity that is produced when the energy of falling water is used to turn turbines of an electric generator Does not produce any pollution It does however, produce environmental concerns Requires the building of a dam so water levels can be raised Many acres behind the dam are flooded

Hoover Dam

Wind Power Wind power is another resource that is renewable and can be used to produce electricity Wind turns the blades of a turbine Turbine powers an electric generator If winds blow at least 32km/h electricity produced Does not cause air pollution

Nuclear Power Makes use of the nuclei of atoms Nuclear energy is released when billions of atomic nuclei from uranium are split apart in a nuclear fission reaction Energy is used to produce steam that rotates the turbine blades of an electric generator Does not contribute to pollution Uranium is a nonrenewable resource and mining can disrupt ecosystems Nuclear power plants also produce radioactive waste that can harm living organisms

Geothermal Energy The hot, molten rock deep beneath Earth’s surface is a source of energy, also Geothermal energy is heat energy generated deep within earth that is available only where geysers or volcanoes are located Geothermal power plant in California uses steam produced by geysers Island nation of Iceland was formed by volcanoes and geothermal energy is plentiful About 90% of homes get their electricity by geothermal energy

Solar Energy Most inexhaustible source of energy on Earth Another alternative to fossil fuels In the northern hemisphere parts of buildings (that face south) receive large amounts of sunlight through very large windows Floors and walls are made of materials that absorb heat during the day During the night the stored heat is released slowly, keeping the building warm

Solar Energy How do solar powered calculators and spacecrafts use the sun for electricity? Use cells (photovoltaic) to turn sunlight into electric current PV cells are small and easy to use Only produce energy in light Batteries must also be used in darkness PV cells are too expensive for generating large amounts of electricity Improvements are being made to make them more widely available

What have you learned? What are natural resources? Compare and contrast nonrenewable and renewable resources. Describe advantages and disadvantages of using nuclear power. Describe two ways solar power can be used to reduce fossil fuel use.