Hydroelectricity

1. Hydroelectricity http://ehpnet1.niehs.nih.gov/qa/105-10focus/focus.html

2. http://www.energy.ca.gov/education/story/story-html/chapter06.htmlhttp://www.energy.ca.gov/education/story/story-html/chapter06.html Method of Using Hydroelectricity • Dams trap river water in a reservoir • The moving water turns turbines • Electricity is produced by generator

3. Hydroelectricity http://wwwga.usgs.gov/edu/hyhowworks.html

4. Impacts of Hydroelectricity (1/3) • Atmosphere • Greenhouse gas from decay of biomass in reservoir • More for shallow reservoirs • Vegetations removal  less CO2-O2 Exchange • Bodies of water change climate • Lithosphere • Water causes changes in landscape • Silting up of reservoirs • Less deposition in lower river

5. http://ehpnet1.niehs.nih.gov/qa/105-10focus/focus.html Impacts of Hydroelectricity (2/3) • Hydrosphere • Slows water movement • Reduce flow of water • Affects temperature of water • Water level fluctuate with electric demands

6. Impacts of Hydroelectricity (3/3) • Biosphere • Prevents fish from spawning • Creates and destroys habitats • Reservoir may promotes water related disease • Provides usable water • Loss of plants

7. To ratify the impact • Removal of dams • Build smaller dams • Divert water through pipes to generator instead • Fish ladders

8. Examples • Poorly managed • Costa Rica • Balbina Shallow resourvior

9. Tidal Energy La Rance

10. Tidal Energy How It Works: • A dam stretched across a tidal basin allow the tide to flow into the basin through a sluice. • The elevated water in the basin is utilized for electricity by producingmechanical energy over water wheels.

11. Tidal Energy Pros • Predictable, reliable • Sustainable • Widely available • Few greenhouse gas emissions Cons • Variable power throughout day • Expensive • Potential negative impact on estuaries and shorelines

12. Tidal Energy Effects on Biosphere: • Interruption of ocean wildlife • Potential destruction of estuaries Effects on Atmosphere: • Less gas exchange if marine plants affected Effects on Lithosphere • Potential to change shorelines Effects on Hydrosphere • Disruption of water flow

13. Tidal energy

14. Solar Energy http://www.eren.doe.gov/pro/images/femp.jpg

15. Method of Using Solar Energy • Photovoltaic cells • Makes up of semiconductors • Produces energy when sunlight hits its surface

16. Solar Thermal Electricity • Uses mirror to reflect sunlight to a central receiver • Heat is used to generate electricity • Fluid circulated to drive a generator • http://www.solardev.com/SEIA-makingelec.php

17. Solar Thermal Heater • Solar collector absorbs heat from sunlight • Solar collector then heats the air or water http://www.irish-energy.ie/abouten/main3l.html

18. Impacts of solar energy • Atmosphere • No impacts • Lithosphere • No impacts • Hydrosphere • No impacts • Biosphere • No impacts

19. Indirect cost of solar energy • Battery production • Panel production uses up resources • Uses of land spaces

20. Wind Energy

21. Wind Power-How it is generated • Turbine blades rotate when wind hits them which causes a rotor to turn and then drives an electrical generator

22. Wind Power-Impacts • Atmosphere • NONE, Wind power does not polute the atmosphere • Lithosphere • Wind turbines have to be anchored to the ground which could impact soil structure

23. Wind Power-Impacts • Hydrosphere • None • Biosphere • The building of wind turbines could result in less habitat for animals and plants

24. Wind Energy • Wind Energy is a renewable source of energy • Wind energy is the fastest growing energy source on earth

25. Management of Wind Energy • Wind turbines should be used where there is plenty of wind • More wind turbines should be built because the resource is currently not being used as well as it could be

26. Wind Energy Poorly Managed • The United States has the wind energy potential to supply one and a half times the current electricity consumption but only a very small amount electricity is generated by wind

27. Wind Energy-Well Managed • In Europe wind energy capacity has increased by 40% in the last six years and there is currently enough wind electricity to meet the needs of 5 million people and by 2010 there should be enough for 75 million

28. Geothermal Power

29. Geothermal Power-How It Works • Water travels through pipes deep into the Earth’s surface where the temperature is hotter, the water than turns to steam which drives the turbine

30. Geothermal Power -Impacts • Atmosphere • geothermal plants emit carbon dioxide • Lithosphere • geothermal plants require pipes to be dug through soil and rock to get deep into the earth’s surface

31. Geothermal Power-Impacts • Hydrosphere • Geothermal plants require the use of water in order to produce electricity • Biosphere • The Building of geothermal plants could result in less habitat for animals

32. Management of Geothermal Energy • Buil geothermal plants in areas where heat from magma is closer to the surface of the earth so that it is easier to generate electricity

33. Geothermal Energy-Well Managed • In the Philippines geothermal power provides 27% of the nations total electrical generation

34. Nuclear Energy Three Mile Island

35. Nuclear Energy How It Works: • Uranium atoms are bombarded with neutrons causing fission. • Neutrons from the split uranium atoms collide with other atoms • The energy from fission heats water • Hot water is used to spin turbines

36. Nuclear Energy

37. Nuclear Energy Benefits: • Few greenhouse gas emissions • High energy yield compared to fossil fuels Consequences: • High cost of repairing aging plants • High cost of plant shutdowns • Radioactive waste

38. Nuclear Energy Effects on Biosphere: • Accidents may expose living things to radiation Effects on Atmosphere: • None Effects on Lithosphere • None Effects on Hydrosphere • Water diverted to plant for harnessing energy