Chapter 21: New renewable Energy Alternatives

1. Chapter 21: New renewable Energy Alternatives www.aw-bc.com/Withgott

2. Renewable Energy • sun • wind • geothermal • oceans • hydrogen www.aw-bc.com/Withgott

3. Solar Energy • conversion of hydrogen (H) to helium (He) • each m2 of area receives about one kilowatt of solar energy= seventeen 60 watt light bulbs • therefore each house has enough roof area to generate all it needs using solar panels • passive and active solar energy collection

4. Passive Solar Energy Collection • design of buildings • construction materials are chosen to: • maximize direct absorption of sunlight during winter • keep the interior cool in summer by: • south facing windows • planting vegetation for shade during summer • overhangs to block sun in summer • heat-absorbing construction materials • straw, brick or concrete for example

5. Passive Solar Energy Collection

6. Active Solar Energy • solar panels • solar cookers • photovoltaic cells www.aw-bc.com/Withgott

7. Active Solar Energy • solar panels • few on the roof of a house or building • collection of mirrors • power tower with molten salt creating steam that moves the generator • tubes with oil which creates steam that move turbines

8. Active Solar Energy • photovoltaic cells • collect sun's energy converting it to electrical energy using semiconductors. www.aw-bc.com/Withgott

9. Benefits of PV cell • quiet • safe • require little or no maintenance • no moving parts • no turbine or generator required • each unit lasts 20-30 years

10. Active Solar Energy • allows families to cook without having to gather fuel wood • lessens daily workload • helps reduce deforestation • helps relieve social and environmental stress

11. Benefits of Solar Power • inexhaustible as energy source • enough energy to power earth as long as technology develops • allows decentralized control over power • producing many new jobs • does not pollute

12. Drawbacks of Solar Power localization www.aw-bc.com/Withgott

13. Drawbacks of Solar Power • costs www.aw-bc.com/Withgott

14. Wind Energy • wind turbines • windmills have been used for more than 800 years in Europe • drain wetlands • irrigate crops • grind grain into flour

15. Wind • first wind turbine was created in the late 1800s • rural electrification act 1935 killed its development promoting dams and coal plants • not until the oil embargo of 1973 that the idea was brought back and funding for research was given • low costs • kinetic energy converted into electric energy • different turbines are designed to work at different wind speeds • faster the wind the more energy it generates

16. Wind: fast growing energy sector www.aw-bc.com/Withgott

17. Offshore Wind Turbines • more expensive • more productive • shallow areas • maintenance www.aw-bc.com/Withgott

18. Benefits of Using Wind Power • cleaner • under optimal conditions it is much more effective than any other conventional energy source • small to large scale usage • farmland can lease a small area and still be productive • once built, the costs are only for maintenance • as efficiency increases the cost of electricity decreases

19. Downsides of Wind Power • wind is intermittent and unpredictable • good resourses are mostly away from populations • grid has to be built and that costs money • conspicuous • people object to farms due to aesthetics • not-in-my-backyard syndrome • threat to birds and bats

20. Geothermal Energy • generated deep within Earth • from an area of volcanic activity along two tectonic plates www.aw-bc.com/Withgott

21. Benefits and Limitations • Benefits • reduces emissions relative to fossil fuels • other pollutants it produces are in very small quantities • filters help control pollutants • Limitations • can produce other pollutants like CO2, CH4, NH3 • sources may not be truly sustainable • limited to area where tectonic plates meet • water used for energy corrodes equipment shortening lifetime of the plant • chemicals in the water may pollute the air

22. Ocean Energy Sources • tides • waves • currents

23. Tides • rising and fallen of the ocean level • twice each day • erecting dams across the outlets of the tidal basins • outgoing tide will pass through the turbines generating electricity • no pollution • high impact on the ecology of estuaries

24. La Rance- France • Hydroelectricity from Tidal Waves www.aw-bc.com/Withgott

25. Wave Energy • converting mechanical energy to electricity • harness the motion of wind-driven waves at the ocean surface • greater energy is found in deeper ocean sites • NY

26. Wave Energy Generator www.aw-bc.com/Withgott

27. Currents • marine kinetic energy • essentially like underwater wind turbines • are now been tested in Europe

28. Hydrogen • Benefits • storage of energy generated by sustainable energy is a problem, hydrogen fuels cells are promising • Hydrogen is the fuel and it is abundant • clan, bonds H2 and O2 making water as final product • Drawback • to make the fuel (H2) energy is required and carbon based pollutants are produced • possible risk of depleting ozone from stratosphere if H2 leaks

29. Bloombox or Bloomenergy • stack of silica plates covered with patented solutions on both sides • it converts oxygen into energy with a minute use of energy (gas, electric, biodisel, etc) • one "box" is required for every European home, 2 for every American home • no need of the grid • several companies are already using it in California • EBay • Google • FedEx • CBS 60 minutes 2/21/2010 • The End www.images.buisnessweek.com