1. Chapter 12

2. RESEARCH TEAMS 1. PV Cells New technology / research on increasing efficiency 2. Solar-Generated Hydrogen Fuel Cells 3. Biomass Interesting facts / other countries’ use of biomass 4. Hydroelectric (conceptual) Summarize differences between Large, Small, Micro, Pico, Underground 5. Hydroelectric (case studies) Impact (env.&human) of 3 largest dams in the world. 6. Wind Various types & new technologies 7. Tidal Why is it not used more? 8. Thermal (OTEC) Environmental impact 9. Ocean Waves Why is it not used more? 10. Geothermal How do home heat pumps work?

3. Presentation Requirements:  All info required on the notes for your section  Added requirements from the previous slide (small bullet point)  Visuals / GIFs / Animations to support your content  No more than 8 minutes to present. Clear & Concise.  NOTE: For your Test, you’re responsible for the textbook chapter. For the IB Exam, this is the goal:

4. HOW DO WE MAKE ENERGY???

6. Passive Solar Energy

8. Active Solar Energy -uses a collecting device

11. SOLAR ENERGY Light energy harnessed from the sun Photovoltaic Cells (solar panels) are very expensive to build and install… but once you’ve got them, you have free energy! (Last time I checked, sunlight was free!)

12. Solar Energy  PROS Low pollution Low maintenance Good for rural areas Can be incorporated into roofing material. Sun is FREEEEEEE!!  CONS Only 10-15% efficient ○ New R&D is proving to be closer to 33%!! Large Scale Use needs lots of land (solar farms) High startup costs. Energy can’t be stored long-term.

16. Solar-Generated Hydrogen “FUEL CELLS”

17. Hydrogen Fuel Cell

18. Hydrogen  PROS No pollution no SO x or NO x or PM …only water & heat Can be stored & transported (liquefied fuel) H is 2X as efficient as gasoline  CONS Produces NO x (small amount) Only 8% efficiency Little/No infrastructure Vehicles not widely available

19. Direct vs Indirect Solar Energy  DIRECT SOLAR Solar panels Solar-generated hydrogen  INDIREC T SOLAR Biomass Wind Hydropower ****************************************************************  BUT THERE ARE OTHER SOURCES! Oceans (wave mov’t, thermal, tidal mov’t) Geothermal (earth’s heat) Pumped Storage Reservoirs (gravity) Cogeneration (get heat when you make electricity) Conservation & Increased Efficiency

20. Biomass

21.  Biomass energy, or "bioenergy“  Energy from plants and plant-derived materials, crop waste, or animal waste  Burned for energy  Most primitive energy source on earth

22. Biomass  Advantages: Renewable if managed properly Can be found worldwide Lower landfill use by burning wastes Planting trees can provide a Carbon Sink (counteracts the CO 2 )  Disadvantages: Air pollution!!! crops take up a lot of land and water; planting and harvesting take lots of energy; crops are not available year round Biomass crops take up land that could be used for food… increases food costs Increased soil erosion, desertification, and water supply degradation

23. Biofuels

24. Biomass can be converted directly into liquid fuels, called "biofuels,” to be used for transportation Ethanol is an alcohol created from biomass (usually corn) Biodiesel is made by combining alcohol (usually methanol) with vegetable oil, animal fat, or recycled cooking grease. Blended with gasoline, both increase vehicle performance and cut down carbon monoxide and other smog-causing emissions. Some types (biogas = CH 4 is quite clean)  Heavy government subsidies  30-40% of the energy in starting material is lost in the alcohol conversion process

25. WIND ENERGY Using wind to turn aerogenerators or wind turbines to generate electricity. 1. Wind turns turbine… 2. Turbine spins a generator… 3. Generator makes electricity

27. WIND ENERGY Coastlines/offshore Islands Tops of mountains In the plains Why is it Indirect Solar Energy??? ○ Sun  Temp ○ Temp  Pressure ○ Pressure  Wind PROS Widely used, cost efficient No air pollution Combined w/ agriculture = double land-use! Potential for much offshore wind energy CONS Birds/Bats killed Loud Ugly Expensive initially ********************************************************************

28. HYDROELECTRIC ENERGY Running water in rivers turns turbines inside dams to generate electricity.  Expensive!  Floods the area  Changes natural flow  Affects fish migration  Reservoir-Induced Seismicity  Water-borne diseases (schistosomiasis) Creates reservoir for recreation Prevents flooding 19% (world) & 9% (USA) power Great potential for LEDCs

30. TIDAL & WAVE ENERGY  Tidal dams are built across bays… High Tide: water goes into a reservoir, pushing turbines. Low Tide: water recedes, pushing turbines  Wave Dams are built anywhere in the water… As waves rise and fall, air is pushed into and out of a turbine tunnel

31. TIDAL ENERGY WAVE ENERGY

33. Ocean Thermal Energy Conversion  Uses temperature differences in the ocean to run a turbine/generator.  Requires another liquid with a low boiling point ammonia, propane, etc It’s never burned… it only changes physical state (liquid  gas  turns turbine  back to liquid) Video: http://www.youtube.com/watch?v=x59MptHscxY

34. Ocean Thermal Energy Conversion

35.  Great in the tropics!!! (Hawaii)  No pollution  Reusable liquid material (ammonia, etc)   Unclear impact on marine organisms (Δtemp)   Inefficient so far (3-4%)   Not on a large scale… need more R&D!   Expensive due to inefficiency

36. GEOTHERMAL ENERGY Hot water from deep underground creates steam The steam turns turbines which generate electricity How does digging the wells for this type of energy affect the environment?

38. Pros & Cons – geothermal  great in geologically active areas (volcanic = Iceland, western USA, Japan, Philippines)  inexpensive, efficient, reliable  not land intensive  minimal air pollution  geothermal heat pumps can be used for homes (small scale)   renewable or not?   small amt of H 2 S gas   can cause subidence

40. Pumped Storage Reservoirs  Pump water uphill at night (low electricity cost)  Water flows downhill during day to generate power Just like in a normal hydroelectric dam

41. Pumped Storage Reservoirs

42. Cogeneration  Aka “Combined Heat & Power” Burn some fuel for electricity Heat is also used to make steam Steam turns a turbine for electricity Heat is also used to heat buildings & other uses. Steam is condensed back to water for reuse.  Get more for your money!  Very efficient and cost-effective.  Great for small scale (restaurants, hotels, etc)

43. CAFÉ standards  Corporate Average Fuel Economy  Standards for average fuel economy  Guidelines are set by EPA.