1. Renewable = Inexhaustible

2. Common Renewable Energy Sources http://www.srpnet.com/environment/graphics /RenewablesChart.gif Solar Wind Hydro Geothermal Biomass

5. “Direct” Biomass Energy = No Conversion

6. “Indirect” Biomass Energy = Conversion

7. Biomass: Pros and Cons Pros – Renewable…as long as we keep throwing stuff away! – Proven Technology; existing plants in operation – Cheap! Trash is one of the least expensive raw materials – Reduced carbon footprint compared to traditional fossil fuel sources Cons – Not a huge resource. – “Indirects” require substantial addition energy input – Larger carbon footprint compared to other renewables

8. Geothermal = Earth Heat

9. Geothermal

10. Geothermal: Pros and Cons Pros – Renewable…at least for a very, very long time – Proven Technology; several “pilot plants” in operation – Relatively low operating costs – Near zero carbon footprint Cons – Limited number of suitable locations – Questions about long term effects; Earthquakes? Drinking water? – Questions about “scalability”