• Coal-remains of plants that have undergone carbonization
• Occurs when partially decomposed plant material is buried in swamp mud and becomes peat
• Types of Coal-peat, lignite, bituminous, anthracite
• Advantages
– Enormous reserves, cheap to mine, use as electricity
• Disadvantages
– Recovery can be dangerous and hazardous-types of mining
– Air pollution
– Cannot be used for transport purposes
– Non-renewable

• Interesting Facts
– Accounts for 28% of nation’s energy needs
– Powered industrial revolution
– Coal is crushed into powder form and burnt

• Provides 40% of our nation’s energy use
• Found in similar environments and typically occur together
• Formation of petroleum and natural gas
– Microorganisms and plant remains in shallow pre-historic
• Advantages
– Mobile (migrates toward surface), relatively low cost, plentiful for now, easily transported, electricity is proven reliable
• Disadvantages
– Urban air pollution, acid rain, global warming, global tensions, oil spills

• Energy released by reactions w/in atomic nuclei
• Nuclear fission-nucleus of heavy atoms splits into 2 or more fragments-process releases neutrons and energy
• Nuclear fusion-nuclei of small atoms combine to form new, massive nuclei-releases energy
• Advantages
– Burn no fossil fuels, no air pollution, radioactive materials have long half live, cheap source, vast amount of energy in one atom
• Disadvantages
– Separating the uranium isotopes is difficult, uranium is rare, cost of building facility is pricey, radiation, accidents

• Interesting facts
– Accounts for about 11% of the worlds energy demands
– Energy that reaches Earth from sun-nuclear fusion
– Fuel rods last several yrs

• Energy produced by heat w/in the Earth
• Magma heats water-wells are drilled to reach hot water
• Used as source of heat or sources of power to drive turbines-generate electricity
• Problems
– Need large potent source of heat (magma) deep enough to apply enough pressure and slow cooling
– Steam and hot water lasts 10-15 hrs
– Not expected to provide high % of worlds growing energy needs

• Electrical energy produced by flow of water, tides
• Dams hold back water, control the flow, water spins turbines which turn generators that produce electricity
• Contributes to 5% of country’s demands
• Many occur in SE and Pacific NW of U.S.
• Problems
– Dams have finite lifetimes, rivers deposit sediment
– Availability of sites

• Wind is movement of air, results from air pressure differences caused by sun’s uneven heating of Earth’s surface
• Use movement of air to convert wind energy into mechanical energy-generates electricity
• Advantages
– Almost free, non polluting
• Disadvantages
– Costs of large tracts of land in populated areas
– No wind, no energy
– Need better means of storage
– Noise pollution