1. Energy Energy- the capacity to do work –Work- force through a distance Joule- amount of work done –4 Joules = 1 calorie –Calorie- energy to heat 1 g of water 1°C

2. Power Power- rate of energy flow Watt- measure of power –Kilowatt-hour (kwh) 1000 watts exerted for 1 hour.

3. World Energy Consumption

5. Per Capita Consumption 20 Richest Countries Consume –80% of natural gas –65% of oil –50% of coal U.S. and Canada consume 25% of available energy

8. How We Use Energy

9. Fossil Fuels Buried organic matter compressed over millions of years Lead to global warming Examples –Coal –Oil –Natural Gas

10. Making Fossil Fuels

11. Coal Pro –Vast Reserves Con –Very dirty –Destructive Extraction

12. Coal-fired Power Plant

13. Mining for Coal

14. A Strip Mine

15. Oil 600 Billion metric tons –½ is recoverable –Gone in 30 years In 2000, proven reserves = 650 billion barrels –Mostly in Middle East Problems –Contains high sulfur –3-6 million metric tons in ocean/year

16. Oil Reserves

17. Refining Oil

18. Hubbert’s Peak

19. Modern Prediction

20. Natural Gas Third largest commercial fuel Only ½ CO 2 as oil Difficult to store and transport Could last 60 years

21. Nuclear Power Derived from splitting atoms Relatively cheap energy Problems –Radiation kills –Nuclear waste

22. Nuclear Fission

23. Nuclear Reactor

24. “Renewable” Energy

25. Renewable as Part of the Whole

26. Solar Energy Using energy from the sun to do work Very little waste

27. Passive Solar

28. Solar Oven

29. Active Solar

30. Photovoltaic Cells

31. Fuel Cells Use electrochemical reactions to produce electricity Hydrogen is hard to store and transport About as efficient as the best fossil fuel engines

32. A Fuel Cell

33. Hydrogen Car

34. Biomass Wood and other plant matter Burns much cleaner than fossil fuels Renewable fuel source 40% of world’s population uses wood –Leads to deforestation

35. Hydropower Falling water has a lot of energy In 1925, 40% of world’s energy came from hydropower Totally destroys ecosystems

36. Hydroelectric Dam

37. Wind Energy Pros –Very Clean –Very Abundant Cons –Requires expensive storage

38. U.S. Wind Potential

39. Wind Generator

40. Renewables

41. Geothermal, Tidal and Wave Energy Geothermal –Only useful in a few places Tidal and Wave Energy –Lots of energy, but very hard to harness –Potentially huge environmental impacts

42. Geothermal Energy

43. Wave Energy