1. Alternative Energy Sources 90% of the energy used today is in the form of fossil fuels. Forms of energy OTHER than fossil fuels are termed “alternative” energy sources.

2. Alternative energy sources can be divided into two main categories. 1)Non-renewable energy sources -nuclear power -geothermal power

3. Geothermal Energy: heat energy from the Earth -the conversion of natural heat from the Earth’s interior to heat buildings and generate electricity. -considered a non-renewable source when extraction rates are greater than supply.

5. People bathing in Blue Lagoon near Grindavik, Iceland- hot springs!

6. 2) Renewable Energy Sources -Solar power -Wind power -Hydropower -Ocean currents/tidal -Biomass energy

7. Solar Energy The amount of incoming solar energy is immense. -in 10 weeks, the amount of incoming solar energy would equal the energy of all known fossil fuel reserves. -Distribution is variable, due to climate,location on Earth, etc…

10. Photovoltaic Solar: Electricity is created directly from special solar panels.

14. Hydrogen Power: Hydrogen has the potential to be the largest energy source of all. Clean Burning (only water as exhaust!) Inexhaustible supply, which is recycled No fancy new drilling technology needed!

15. Water Power: Hydro-power is a good alternative energy source, because it is essentially unlimited. -Direct hydro-power: using moving water to turn machinery, such as a mill. -Hydro-electric power: using the power of water to turn an electric generator, such as in a dam.

17. Hydroelectric Power Generation Power is generated by harnessing the energy of falling water. The greater the difference in water level, the more energy

19. Tidal/Current Power: generation of electricity from movement of ocean tides or currents. Rising tides are trapped behind a dam, then released to turn a generator. Also some work on ocean buoys that harness the movement of water to generate electricity.

24. Wind Power: generation of electricity using wind to turn turbines. Free energy, but needs to be in an area that has constant winds with enough velocity to warrant placing windmills. Best used in particular sites with a good steady supply of wind.

28. Biomass Energy: energy from organic matter. Probably the first source of energy for man, this energy is renewable and abundant. Already in use in many places, such as sugar plantations and saw mills. Also includes the burning of urban waste, in “trash to steam” plants.

29. Outlook: Biomass fuel will continue to be a large part of the alternative energy picture. However: Environmental degradation can and will occur if the biomass is not harvested in a renewable manner. Burning biomass causes pollution, especially air pollution, and leaves ash behind. The ash can be very toxic.

30. The Future of Alternative Energy Alternative energy sources will play larger roles in the future, but each needs to be utilized in a manner which damages the environment as little as possible. Energy sources will need to be mixed, to use them to their maximum potential.