Energy Recourses Nearly all the Earth’s energy come from the sun Traditional Energy sources (such as wood) Fossil Fuel (coal, oil, gas) Alternative Energy sources (nuclear Wind, solar, water, geothermal) Conservation of Energy resources

Traditional sources Wood- primary source of energy for much of the world. Field Crops-burning residue of the crops Fecal material- used where wood and other materials are scarce. Peat-sponge material from bottom of bogs

Fossil Fuels- coal Nonrenewable energy Coal-compressed organic matter. Different carbon concentration, different burning temps. Used in electric power plants Releases carbon, sulfur and nitrogen oxide.

Fossil Fuel -oil Petroleum- Means Rock Oil Shallow crude oil deposits Often seeps up through cracks or faults Deposited from organisms thousands of years ago at bottom of rivers and seas.

Fossil Fuel- Gas

Alternative Energy Resources Solar energy Hydro electric Energy Geothermal Energy Wind Energy Nuclear Energy Bio Mass

Solar Energy Passive solar heating- capture sunlight and convert it to heat Concrete, brick, stone tile Active Solar heating- use of solar panels, fans, pumps Photovoltaic cells- sun hits and releases electrons which is stored in electric cells

Hydroelectric Energy Falling water turns turbines Hover Dam Niagra Falls Provides 20% of the worlds electricity Non-polluting, recreational activities, flood control, drinking water Energy from Waves. May disturb coastal eco systems

Geothermal Energy Originates from the earth’s interior. Geyser-Old Faithful Water trapped under ground is heated by earths interior Used in power plants to produce electricity Advantages- abundant and reliable energy. Can cause air pollution and clog pipes with minerals Disadvantages- abundant only where it naturally exists.

Wind Energy Wind turbines Converts mechanical energy from the wind to electrical energy Nonpoluting Constant supply Disadvantages Noisy Need constant supply of wind.

Nuclear Energy Nuclear fission- atoms are split into smaller atoms and gives off electrons. Does not give off greenhouse gasses Disadvantages High operating cost Disposal of nuclear waist Public concern for safety TMI, Chernobyl Urcraine Japan’s nuclear plant