1. Renewable Energy Chapter 18

2. 18-1 Renewable Energy Today Objectives 1. List six forms of renewable energy, and compare their advantages and disadvantages. 2. Describe the differences between passive solar heating, active solar heating, and photovoltaic energy. 3. Describe the current state of wind energy technology. 4. Explain the differences in biomass fuel use between developed and developing nations. 5. Describe how hydroelectric energy, geothermal energy, and geothermal heat pumps work.

3. Renewable Energy – energy from sources that are constantly being formed Solar, wind, hydro, and geothermal

4. Solar Energy • Most all renewable energy comes directly or indirectly from the sun

5. Passive Solar Energy • Use the sun’s energy to heat something directly

6. Characteristics of a passive solar home • Ceilings heavily insulated • Thick walls and floors • South-facing double paned windows • Shade trees for summer • Insulated windows

8. Active Solar Heating • Uses collectors to gather the sun’s energy • Collectors on roofs capture the sun’s energy and heat a liquid which flows to a heat exchanger which heats water for the building

10. About 8% energy used in US is used to heat water

11. Photovoltaic cells convert the sun’s energy into electricity • No moving parts • Produce a small electric current

12. Need extended periods of sunlight • Electricity stored in batteries • Provides about 1 million households with electricity worldwide

15. Concentrated Solar Thermal 300 foot Power Tower near Seville, Spain

16. Concentrated Solar Thermal 300 foot Power Tower near Seville, Spain

17. Olmedilla Photovoltaic Park - Spain 15 of 20 largest solar power plants in the world 280 acres 162,000 pv panels Electricity for 40,000 homes

18. Nellis Solar Farm, Nevada

19. Solar updraft tower - Australia

20. Wind Power • Converts the movement of wind into electrical energy • Faster growing energy source

21. Tehachapi Wind Turbines

22. Number of MWatts by state, March 2007 As of third quarter, 2009 there are 31,100 MW of electricity produced by wind in US

25. Biomass • When plant material, manure, or any other organic matter is used an energy source • Include wood and dung (can cause air pollution and habitat destruction)

27. Other sources of biomass include methane (gas given off by decomposition) and alcohol (ethanol- fermentation of agriculture wastes) • Gasohol – blend of gasoline and ethanol; less air pollution than gas

28. Hydroelectricity • energy produced by moving water • 20% of the world’s electricity • Dams are expensive to build but inexpensive to operate

29. Advantages: No air pollution, provide flood control, water for drinking, agriculture, industry, and recreation • Disadvantages: disrupts ecosystems, displacement of people, potential for dam failure, sedimentation

30. Hydroelectric dams are the standard when we think of hydro power

31. Wave powered electrical generators

32. Geothermal • energy from the heat in the Earth’s crust • Pump water heated water from rock formations and use the water or steam to power turbines

33. Some homes use geothermal heat pumps • US is the world’s largest producer of geothermal heat pumps

35. 18-2 Alternative Energy and Conservation Objectives 1. Describe three alternative energy technologies. 2. Identify two ways that hydrogen could be used as a fuel source in the future. 3. Explain the difference between energy efficiency and energy conservation. 4. Describe two forms of energy-efficient transportation. 5. Identify three ways that you can conserve energy in your daily life.

36. Look around the room…..can you find any instances were energy is being wasted??

37. Alternative energy- describes energy sources that are still in development

38. Tidal Power • Uses the 2 tide changes • Tide difference needs to be around 16 m • Cost to build is high

40. Ocean Thermal Energy Convection • Warm surface water is used to boil sea water • Water at lower pressure boils at a lower temperature

42. Boiling water turns turbine • Expensive to operate • Environmental effects unknown

43. Hydrogen • Hydrogen is found in every molecule of every living thing • Produces water vapor as a byproduct • Takes energy to produce the pure hydrogen

44. Energy can be stored in fuel cells (produces electricity chemically) Honda FCX Clarity

45. Energy Efficiency • How do we reduce energy use? • Lifestyle changes • Upgrade distribution grid • Upgrade industrial motors • Newer steel manufacturing methods • Recycling

46. Increase energy efficiency • The percentage of energy put into a system that does useful work energy out/energy in X 100 • More than 40% of energy produced is wasted

48. Super Grid technology • Allows for mixed use of stable and intermittent energy sources • Utilizes electricity storage technology • Higher efficiency in delivering electricity over long distances • Decentralization of electricity generating plants • Close or reduce usage of coal-fired electric plants • Duke Power, Smart meters