1. Renewable Energy

2. Solar Solar energy is harnessing energy from the sun’s rays – Passive Solar – Placing buildings strategically to take advantage of the sun’s heat Example: Log Homes – Active Solar – uses solar panels to convert energy into a usable form such as electricity

3. Benefits of Solar: – Readily available – Renewable – Fairly simple system – Pollution free energy source – Can sell back extra energy to the power company Drawbacks of Solar: High start up cost for active solar energy system Location dependent (Seattle would not be a good city for solar energy)

4. Wind Wind energy is converted into a usable energy form by using wind turbines www.lacoastpost.com www.windenergyplanning.com

5. Benefits of Wind Power: – Readily available – Can sell back extra power – Pollution free energy source Drawbacks of Wind Power: – Disrupts migration patterns – Turbine farms are not aesthetically pleasing – Turbines are expensive – Good for specific locations only

6. Hydro Hydro power is mechanical energy derived from water Most hydropower is generated by damming rivers Using waves or ocean currents is being researched as a source of hydropower www.southeastasia.biz

7. Three Gorges Dam in China www.livescience.com

8. Three Gorges Dam 1.5 miles long 574 feet deep $23 billion 13 cities and 1,300 villages were flooded

9. www.howstuffworks.com

10. Benefits of Hydropower – Readily available – No pollution produced – Constant source of power Drawbacks of Hydropower – Damming rivers disrupts ecosystems, causes sediment to build up and disruptst he natural flow of a river

11. Geothermal Geothermal energy uses natural underground heat sources When heat escapes the earth in the form of steam, the steam is used to turn a steam turbine which converts the heat energy into electrical energy

12. Benefits of Geothermal: – When drilled correctly, little pollution is produced – Takes up a relatively small area, does not disrupt the landscape Drawbacks of Geothermal: – Can only be used in a limited capacity – Very location specific – May run out of steam – May release hazardous gasses or minerals if drilled improperly

13. Biomass Biomass is burning biomass fuel in a specialized burner. Steam generated turns a steam turbine which turns mechanical energy into electrical energy

14. Biomass at the Denver Zoo! Trash and animal waste is converted into pellets The pellets are put into a gassifier and heated to 400 degrees! When hot enough, a gas is emitted that is converted by micro gas turbines into electrical energy Denver Zoo

15. Benefits of Biomass – Less waste in landfills Readily available Drawbacks of Geothermal – Not currently available on a large scale basis