RENEWABLE ENERGY

• Biological energy sources

  human labor, animal labor, initial energy occurs in photosynthesis
• Middle age

  wind for sailing, animal power, charcoal, coal on the grounds for fire
• Industrial revolution (1875)


  steam engines - can convert heat energy into forward motion
• Changes in energy sources

  1880-1890
• Energy

  indispensible factor in survival. needed by ppl, nations and the progress of our country.
• Biomass

  matter from recently living organisms which is used for bioenergy production.
• geothermal energy

  thermal energy extracted from the Earth's crust. combines energy from the formation of the planet and from radioactive decay
• Solar power


  uses energy from sun, solar pans transfer sun's energy to heat water
• Hydroelectric


  flowing water is used to turn a urbine which generates electricity
• Conservation


  key faster in saving the world from energy shortage/crisis